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Sample records for billet extrusion process

  1. Modeling operations back extrusion billets thick-walled anisotropic

    OpenAIRE

    ПЛАТОНОВ В.И.; Яковлев, С. С.

    2014-01-01

    The mathematical model is an inverse extrusion thick-walled tube blanks of material having anisotropic mechanical properties cylindrical. Relations are given to assess the kinematics of course materials la, stress and strain states, power operation modes reverse extrusion. The results of theoretical investigations of power modes. You are the manifest effects of process parameters on the power mode of operation isothermal reverse extrusion billets of high anisotropic materials in the short-ter...

  2. Kinematics Performance and Structural Analysis for the Design of a Serial-parallel Manipulator Transferring a Billet for a Hot Extrusion Forging Process

    OpenAIRE

    My, Chu Anh; Parnichkun, Manukid

    2015-01-01

    To reduce the downtime and optimize the use of energy and manpower, a serial-parallel manipulator is designed for transferring heavy billets for a hot extrusion forging station. With the purpose of increasing the structural rigidity and restricting the end-effector (a gripper) so that it always moves in parallel with the ground surface, parallel links are added in between the serial links of the manipulator. This modification of the conventional structure must be considered in the modelling a...

  3. Kinematics Performance and Structural Analysis for the Design of a Serial-parallel Manipulator Transferring a Billet for a Hot Extrusion Forging Process

    Directory of Open Access Journals (Sweden)

    Chu Anh My

    2015-12-01

    Full Text Available To reduce the downtime and optimize the use of energy and manpower, a serial-parallel manipulator is designed for transferring heavy billets for a hot extrusion forging station. With the purpose of increasing the structural rigidity and restricting the end-effector (a gripper so that it always moves in parallel with the ground surface, parallel links are added in between the serial links of the manipulator. This modification of the conventional structure must be considered in the modelling and analysis of the design. This paper addresses a methodology to investigate the kinematics performance and strength analysis of the designed robot. With respect to the parallel links, the constraint equation is derived and put together with the kinematical model. Based on the entire model that is formulated, the inverse kinematics, the transferring time, the reachable workspace, the degree of dexterity and the manipulability index are analysed and discussed to demonstrate its kinematical performance. In addition, to investigate the structural characteristics of the end-effector module, the static displacement and stress distributed on module's components are computed and simulated using the computer-aided finite element method (FEM. These research results are effective and useful in assessing and improving the robot’s design.

  4. OPTIMIZING AN ALUMINUM EXTRUSION PROCESS

    Directory of Open Access Journals (Sweden)

    Mohammed Ali Hajeeh

    2013-01-01

    Full Text Available Minimizing the amount of scrap generated in an aluminum extrusion process. An optimizing model is constructed in order to select the best cutting patterns of aluminum logs and billets of various sizes and shapes. The model applied to real data obtained from an existing extrusion factory in Kuwait. Results from using the suggested model provided substantial reductions in the amount of scrap generated. Using sound mathematical approaches contribute significantly in reducing waste and savings when compared to the existing non scientific techniques.

  5. Extrusion Upsetting Multiple Processing in Sandglass Die

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new method of getting ultrafine grain size has been investigated, which is called "Extrusion Upsetting Multiple Processing in Sandglass Die" or "Sandglass Extrusion" (SE). Since the shape of tested billet can remain unchanged after SE, the billet can be extruded repeatedly in order to get large plastic strain. The ultrafine grain size can be obtained in the billet material due to the large plastic strain and the dynamic recrystallization during SE. The experiments on SE of Zn-5%Al alloy have been done. The SE technology, microstructures, microhardness and superplasticity of tested material after SE have been studied. The experimental results show that the equal-axial ultrafine microstructures can be introduced to the bulk test material during sandglass extrusion. The high strain rate superplasticity can be realized.

  6. 纯镍N6挤压坯料的高温变形行为及加工图%Hot Deformation Behavior and Processing Map of Nickel N6 from Extrusion Billet

    Institute of Scientific and Technical Information of China (English)

    莫戈; 曾攀

    2016-01-01

    目的:以来源于挤压坯料的纯镍N6作为研究对象,分析其高温压缩变形行为及微观组织演化,为挤压工艺参数设计提供有效依据。方法利用Gleeble-1500D热-力模拟试验机,对实验样品在温度900~1200℃和应变速率0.01~10 s-1范围进行热压缩变形,获得了材料真应力-真应变曲线,利用光镜观察了变形后的微观组织。结果建立了双曲正弦函数形式的本构方程,得到材料的本构参数为Q=272.77 kJ/mol,α=0.01024 MPa-1,n=4.045。基于动态材料模型建立了材料的热加工图,判断材料具有低温低应变速率和高温高应变速率2个适宜的加工区间。结论纯镍N6极易发生晶粒长大,温度和应变速率对变形组织影响显著,在变形条件为1200℃/1 s-1时,晶粒平均尺寸已经到达84.83μm。加工图失稳区间内的微观组织呈现不均匀性,为粗大变形晶粒与细小再结晶晶粒混杂的两级结构,因此在热挤压加工工艺设计中需要避开相应的参数区域。%ABSTRACT:Hot deformation behavior and microstructure evolution of nickel N6 from extrusion billet were studied to help design extrusion process. Specimens were tested at temperature range of 900~1200 ℃ and strain rate range of 0.01~10 s-1 on Gleeble-1500D thermal-mechanical testing device and true stress-strain curves were obtained. Microstructure after deformation was also studied using optical microscope. Hyperbolic-sine and Arrhenius-type constitutive model were obtained with whose parameters of Q=272.77 kJ/mol,α=0.01024 MPa-1,and n=4.045. Processing map was made using DMM model that concluded there were two regions suitable for material processing. Grain size of nickel N6 was prone to grow and significantly impacted by temperature and strain rate. When material was deformed at 1200℃/1 s-1,average grain size was up to 84.83μm. When the material was deformed,the microstructure in the region of instability exhibited in

  7. The cooling processes of metal billets

    Directory of Open Access Journals (Sweden)

    Miram Andrey Olegovich

    2014-03-01

    Full Text Available The article describes various methods for solving problems of nonstationary heat transfer. Nonstationary heat transfer is characterized by the fact that the temperature changes not only from point to point, but also in time. The process of cooling metal blanks must be considered a transient thermal conductivity. When solving the problem of cooling metal blanks we need to find the temperature change in the section. The authors show the complexity of the tasks of nonstationary heat transfer. If we consider the process of cooling metal billets as a complex process, in which the addition of nonstationary heat transfer is presented as a process of heat transfer by radiation, great probability of errors in calculations occurs. There is the feasibility of the use of experimental researches of cooling processes for metal blanks after continuous casting, in order to determine the error in the calculated values.

  8. Three-dimensional analysis of extrusion process utilizing the physical modeling technique

    Energy Technology Data Exchange (ETDEWEB)

    Sofuoglu, H. (Technical Univ., Trabzon (Turkey)); Rasty, J. (Texas Tech Univ., Lubbock (United States))

    1993-03-01

    The purpose of this study was to simulate the metal extrusion processes via three-dimensional physical modeling technique. Plasticine was utilized as the modeling material, while plexiglass was incorporated in the design and fabrication of a lab scale extrusion apparatus. The extrusion setup was designed to accommodate dies of different semi-cone angle while also making it possible to change the extrusion ratio R. Cylindrical billets were prepared utilizing alternating layers of two colors of plasticine. Extrusion of cylindrical billets was conducted at three different reduction ratios and three different die angles for each reduction ratio. Dissection of the extruded billets along a centroidal plane revealed the internal deformation patterns which were subsequently utilized for determining the effect of the die angle and extrusion ratio on the state of strain in the final product as well as the required extrusion loads.

  9. Effect of extrusion stem speed on extrusion process for a hollow aluminum profile

    International Nuclear Information System (INIS)

    Highlights: ► Extrusion stem speed has significant effects on extrusion process. ► An optimum value of stem speed exists for uniform metal flow distribution. ► A higher stem speed leads to a higher required extrusion force. ► A high stem speed leads to an improved welding quality of aluminum profile. - Abstract: Extrusion stem speed is one of important process parameters during aluminum profile extrusion, which directly influences the profile quality and choice of extrusion equipments. In this paper, the extrusion process of a thin-walled hollow aluminum profile was simulated by means of the HyperXtrude commercial software. Through a serial of numerical simulation, the effects of stem speed on extrusion process, such as metal flow behavior at die exit, temperature distribution, extrusion force, and welding pressure, have been investigated. The numerical results showed that there existed an optimum value of stem speed for flow velocity distribution. With the increasing stem speed, the temperature of the extrudate and required extrusion force increased, and the welding quality of extrudate would be improved. Through comprehensive comparison and analysis, the appropriate stem speed could be determined for practical extrusion production. Thus, the research results could give effective guideline for determining initial billet and die temperature and choosing the proper extrusion press in aluminum profile industry.

  10. Uniformity and continuity of effective strain in AZ91D processed by multi-pass equal channel angular extrusion

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-hua; LUO Shou-jing; DU Zhi-ming

    2008-01-01

    AZ91D magnesium alloy was processed by equal channel angular extrusion(ECAE). The influence of extrusion temperature, extrusion pass and extrusion route on the ultimate strength of the extruded billet was analyzed. The process of multi-pass extrusion was simulated with the method of finite element analysis, and the continuity and uniformity of effective strain in multi-pass extrusion were investigated. The results show that extrusion pass plays the most important role in improving the ultimate strength of AZ91D magnesium alloy, the extrusion route is the second, and the extrusion temperature is the last. From the numerical simulation, there exists the continuity of the accumulated deformation in multi-pass extrusion and the effective strain increases linearly. The tendency of the strain uniformity is different in multi-pass extrusion with extrusion routes. The results of experiment agree with those of numerical simulation.

  11. Optimal design of an extrusion process for a hinge bracket

    Energy Technology Data Exchange (ETDEWEB)

    Na, Geum Ju; Jang, Myung Geun; Kim, Jong Bong [Seoul National University, Seoul (Korea, Republic of)

    2016-05-15

    This study considers process design in forming a hinge bracket. A thin hinge bracket is typically produced by bending a sheet panel or welding a hollow bar into a sheet panel. However, the hinge bracket made by bending or welding does not have sufficient durability in severe operating conditions because of the stress concentration in the bended region or the low corrosion resistance of the welded region. Therefore, this study uses forming to produce the hinge bracket part of a foldable container and to ensure durability in difficult operating conditions. An extrusion process for a T-shaped hinge bracket is studied using finite element analysis. Preliminary analysis shows that a very high forging load is required to form the bracket by forging. Therefore, extrusion is considered as a candidate process. Producing the part through the extrusion process enables many brackets to be made in a single extrusion and through successive cutting of the extruded part, thereby reducing the manufacturing cost. The design focuses on reducing the extrusion load and on ensuring shape accuracy. An initial billet is designed to reduce the extrusion load and to obtain a geometrically accurate part. The extruded part is bent frequently because of uneven material flow. Thus, extrusion die geometries are designed to obtain straight parts.

  12. FEM Modeling of Extrusion of Square Billet to Square Product Through Cosine Dies

    Science.gov (United States)

    Rout, Akshaya Kumar; Maity, Kalipada; Sahoo, Susanta Kumar

    2016-06-01

    The die profile plays an important role in reduction of extrusion load, evolution of uniform micro-structure and overall improvement of surface integrity of reproduct. In the present investigation, a numerical FEM approach has been carried out for extrusion through cosine die profile using DEFORM-3D software for steady state deformation using rigid plastic material. The extrusion load has been predicted. The comparison made with the experimental results. To show the validity and effectiveness of the result, experiments on hot extrusion were performed, and the results of computation are found to be in good agreement with those of the experiments.

  13. The Effects of Process Parameters on Evolutions of Thermodynamics and Microstructures for Composite Extrusion of Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    H.-J. Hu

    2013-01-01

    Full Text Available To research the effects of process parameters on evolutions of extrusion force and temperature rise and microstructures for composite extrusion of magnesium alloy which includes initial extrusion and shearing process subsequently and is shortened for “ES” in this paper, the ES extrusion process has been researched by using finite element modeling (FEM technology. The rules of temperature rise and the extrusion force varying with process parameters have been developed. The thermal-mechanical coupling finite element models including the geometric and FEM models and solution conditions were applied to calculate the effective strain and temperature and extrusion force during ES extrusion. The maximum temperature rises in the billets do not increase with billet temperature rising. The temperature of rod surface increased continuously with development of ES extrusion. The evolutions of extrusion load curve and effective stress and temperature can be divided into three stages obviously. Extrusion experiments have been constructed to validate the FEM models with different process conditions. The simulation results and microstructure observation showed that ES process can introduce compressive and accumulated shear strain into the magnesium alloy. The ES extrusion would cause severe plastic deformation and improve the dynamic recrystallization during ES extrusion. The microstructures show that ES is an efficient and inexpensive grain refinement method for magnesium alloys.

  14. Process optimization diagram based on FEM simulation for extrusion of AZ31 profile

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The ram speed and the billet temperature are the primary process variables that determine the quality of the extruded magnesium profile and the productivity of the extrusion operation.The optimization of the extrusion process concerns the interplay between these two variables in relation to the extrudate temperature and the peak extrusion pressure The 3D computer simulations were performed to determine the eriects of the ram speed and the billet temperature on the extrudate temperature and the peak extrusion pressure,thereby providing guidelines for the process optimization and minimizing the number of trial extrusion runs needed for the process optimization.A case study on the extrusion of an AZ31 X-shaped profile was conducted.The correlations between the process variables and the response from the deformed material,extrudate temperature and peak extrusion pressure,were established from the 3D FEM simulations and verified by the experiment.The research opens up a way to rational selection of the process variables for ensured quality and maximum productivity of the magnesium extrusion.

  15. Microstructure Evolutions during the Hot Extrusion Process of AZ 31B Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    LI Luoxing

    2009-01-01

    The hot bulk deformation processes (such as extrusion, forging and rolling) are efficient ways to produce fine microstmcture. The effects of extrusion parameters on the evolved microstructure of directly extruded AZ 31B magnesium alloy were investigated. Extrusion processes were carried out at five different combinations with ram speed ranging from 2 to 8 mm·s-1 and billet temperature ranging from 350 to 450 ℃. The experimental results show that the peak extrusion force decreases with increase in billet temperature and decreases in ram speed. During all the extrusion the profile temperature and die temperature rise continuously. Small particles of secondary phase (β-Mg17A112) are uniformly distributed near the edge of the extruded profiles whereas their distribution is nonuniform in the centre of the extrudates. The size of secondary phase particles present in the central region of the specimens was found to increase with billet temperature and extrusion speed. All the specimens showed mixed microstructure-In the central region of the specimen, low volume fraction of dynamically recrystallized fine grains presented at the grain boundaries of original coarse grains; but near the edge region, the microstructure consisted nearly equiaxed free reerystallized grains.

  16. Modeling of Heat Transfer and Solidification Process of Spray Formed Billet

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, modeling of heat transfer and solidification process of spray formed billet was established. Thermal profiles of billet at various spray time and under various spray forming conditions were calculated numerically. The simulation results are consistent with the actual experimental results.

  17. Extrusion processing : effects on dry canine diets

    NARCIS (Netherlands)

    Tran, Q.D.

    2008-01-01

    Keywords: Extrusion, Canine diet, Protein, Lysine, Starch gelatinization, Palatability, Drying. Extrusion cooking is a useful and economical tool for processing animal feed. This high temperature, short time processing technology causes chemical and physical changes that alter the nutritional and

  18. Effects of processing parameters on the extrusion by continuous variable cross-section direct extrusion with 7A09 aluminium alloy

    Science.gov (United States)

    Li, Feng; Wu, Hongbin; Qin, Minghan

    2016-02-01

    In order to study the effects of processing parameters on the continuous variable cross-section direct extrusion (CVCDE), taking 7A09 aluminium alloy for example, the extrusion speed and forming temperature and the friction factor as key processing parameters are applied to research by finite element (FE) simulation. The research result showed that the extrusion speed had a significant influence on the maximum temperature of the billet, at the same time, both decreasing the friction factor and increasing forming temperature within a certain range were beneficial to reduce extrusion load. Both forming temperature and the extrusion speed were inversely linked to extrusion load, but the friction factor was directly proportional to extrusion load. Forming temperature had a far more important influence on extrusion load by comparison: when forming temperature increased from 380∘ to 430∘C, the peak value of extrusion load decreased by 25.6% and the flow uniformity of extruded product got improved. The process window based on both the press limit and surface defects limit was established and the most reasonable forming temperature was 405∘C under this process condition, which provided theoretical basis for formulation process of 7A09 aluminium alloy on the CVCDE extrusion.

  19. Extrusion processing : effects on dry canine diets

    OpenAIRE

    Tran, Q.D.

    2008-01-01

    Keywords: Extrusion, Canine diet, Protein, Lysine, Starch gelatinization, Palatability, Drying. Extrusion cooking is a useful and economical tool for processing animal feed. This high temperature, short time processing technology causes chemical and physical changes that alter the nutritional and physical quality of the product. Effects of extrusion on the feed quality for other animals than pets have been well recognized. Our studies investigated to what extent extrusion and/or drying of a c...

  20. Means of determining extrusion temperatures

    Science.gov (United States)

    McDonald, Robert E.; Canonico, Domenic A.

    1977-01-01

    In an extrusion process comprising the steps of fabricating a metal billet, heating said billet for a predetermined time and at a selected temperature to increase its plasticity and then forcing said heated billet through a small orifice to produce a desired extruded object, the improvement comprising the steps of randomly inserting a plurality of small metallic thermal tabs at different cross sectional depths in said billet as a part of said fabricating step, and examining said extruded object at each thermal tab location for determining the crystal structure at each extruded thermal tab thus revealing the maximum temperature reached during extrusion in each respective tab location section of the extruded object, whereby the thermal profile of said extruded object during extrusion may be determined.

  1. Effects of electromagnetic field and lubricate condition on the surface quality of magnesium alloy billet during LFEC processing

    Institute of Scientific and Technical Information of China (English)

    LE QiChi; ZHANG ZhiQiang; CUI JianZhong

    2009-01-01

    The microstructures of the magnesium billets could be improved markedly by low-frequency electro-magnetic casting (LFEC) processing. In fact, the low-frequency electromagnetic field (LFEF) also has favorite effect on the surface quality of billet. However, few public reports on the surface quality of LFEC magnesium billets could be found. Therefore, a new crystallizer with a metal internal sleeve to-gether with a kind of lubricant was designed aiming at lowing surface turning quantity, and the effects of casting velocity, electromagnetic condition and lubrication on the surface quality of magnesium billets were investigated. The results indicate that LFEF together with the lubricate condition would be responsible for the surface quality of the billets, and the high surface quality billets could be achieved by optimizing the casting conditions.

  2. Developments in finite element simulations of aluminium extrusion

    NARCIS (Netherlands)

    Lof, Joeri

    2000-01-01

    Aluminium extrusion is a forming process used to produce profiles. A large variety of profiles can be made by pressing a billet of hot aluminium through a hole that closely resembles the required cross-section of the profie. At the present time, design of extrusion dies and operation in extrusion co

  3. Modelling of the radial forging process of a hollow billet with the mandrel on the lever radial forging machine

    Science.gov (United States)

    Karamyshev, A. P.; Nekrasov, I. I.; Pugin, A. I.; Fedulov, A. A.

    2016-04-01

    The finite-element method (FEM) has been used in scientific research of forming technological process modelling. Among the others, the process of the multistage radial forging of hollow billets has been modelled. The model includes both the thermal problem, concerning preliminary heating of the billet taking into account thermal expansion, and the deformation problem, when the billet is forged in a special machine. The latter part of the model describes such features of the process as die calibration, die movement, initial die temperature, friction conditions, etc. The results obtained can be used to define the necessary process parameters and die calibration.

  4. Effect of die shape on the metal flow pattern during direct extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, N.; Solomon, I.

    2010-07-01

    The geometric shape of the tools is the main factor by which an optimum technological process can be developed. In the case of extrusion process the strain distribution and other important variables that influence material structure, such as hydrostatic stress, are strongly dependent on the geometry of the die. Careful design of the extrusion die profile can therefore control the product structure and can be used to minimise the amount of inhomogeneity imparted into the product. A possibility to minimise the amount of product inhomogeneity is the using of a flat die with a fillet radius in front to the bearing surface with leads to a minimum dead zone and consequently to a minimum friction at billet-container interface. In the case of aluminium alloy type 2024, for an extrusion ratio of R=8.5, good results were obtained with a fillet radius of 3.0 mm. The experimental data have been used for the finite element numerical simulation of the extrusion process. The data obtained by numerical simulation with FORGE2 programme confirm the theoretical and experimental outcomes. The aim of this paper is to study the influence of such flat die on the material flow during direct extrusion process and consequently on extruded product microstructure and mechanical properties. (Author).

  5. Production Process of Biocompatible Magnesium Alloy Tubes Using Extrusion and Dieless Drawing Processes

    Science.gov (United States)

    Kustra, Piotr; Milenin, Andrij; Płonka, Bartłomiej; Furushima, Tsuyoshi

    2016-06-01

    Development of technological production process of biocompatible magnesium tubes for medical applications is the subject of the present paper. The technology consists of two stages—extrusion and dieless drawing process, respectively. Mg alloys for medical applications such as MgCa0.8 are characterized by low technological plasticity during deformation that is why optimization of production parameters is necessary to obtain good quality product. Thus, authors developed yield stress and ductility model for the investigated Mg alloy and then used the numerical simulations to evaluate proper manufacturing conditions. Grid Extrusion3d software developed by authors was used to determine optimum process parameters for extrusion—billet temperature 400 °C and extrusion velocity 1 mm/s. Based on those parameters the tube with external diameter 5 mm without defects was manufactured. Then, commercial Abaqus software was used for modeling dieless drawing. It was shown that the reduction in the area of 60% can be realized for MgCa0.8 magnesium alloy. Tubes with the final diameter of 3 mm were selected as a case study, to present capabilities of proposed processes.

  6. IMPORTANT DEGRADATIONS IN POLYETHYLENE TERAPHTALATE EXTRUSION PROCESS

    Directory of Open Access Journals (Sweden)

    Şule ALTUN

    2003-01-01

    Full Text Available Polyethylene terephthalate (PET is one of the most used thermo-plastic polymers. The total consumption of PET has been about 30 million tons in the year 2000. Polyester fibers constitute about 60 % of total synthetic fibers consumption. During extrusion, PET polymer is faced to thermal, thermo-oxidative and hydrolytic degradation, which result in severe reduction in its molecular weight, thereby adversely affecting its subsequent melt processability. Therefore, it is essential to understand degradation processes of PET during melt extrusion.

  7. Physical and mathematical modelling of extrusion processes

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Gronostajski, Z.; Niechajowics, A.;

    2000-01-01

    The main objective of the work is to study the extrusion process using physical modelling and to compare the findings of the study with finite element predictions. The possibilities and advantages of the simultaneous application of both of these methods for the analysis of metal forming processes...

  8. Extrusion instability in an aramid fibre spinning process

    NARCIS (Netherlands)

    Drost, S.

    2015-01-01

    The efficiency of polymer extrusion processes can be severely limited by the occurrence of viscoelastic extrusion instabilities. In a para-aramid fibre spinning process, for example, a μm-scale extrusion instability is responsible for the waste of tons of polymer per year. At present, a considerab

  9. IMPORTANT DEGRADATIONS IN POLYETHYLENE TERAPHTALATE EXTRUSION PROCESS

    OpenAIRE

    Şule ALTUN; ULCAY, Yusuf

    2003-01-01

    Polyethylene terephthalate (PET) is one of the most used thermo-plastic polymers. The total consumption of PET has been about 30 million tons in the year 2000. Polyester fibers constitute about 60 % of total synthetic fibers consumption. During extrusion, PET polymer is faced to thermal, thermo-oxidative and hydrolytic degradation, which result in severe reduction in its molecular weight, thereby adversely affecting its subsequent melt processability. Therefore, it is essential to understan...

  10. Aluminium extrusion investigated by theory, experiment and FEM-analysis

    OpenAIRE

    Khorasani, Sepinood Torabzadeh

    2015-01-01

    The process of aluminium extrusion has important influence in metal forming industry because of its ability to produce profiles with different shapes, sizes and complicated geometries. The required extrusion load is depending on the process parameters such as the flow stress of the billet material, velocity field, strain rate distribution, and thermal conditions within extrusion. These conditions are so important for industries, and interesting for academia, that research has been...

  11. Effects of extrusion processing on nutrients in dry pet food

    NARCIS (Netherlands)

    Tran, Q.D.; Hendriks, W.H.; Poel, van der A.F.B.

    2008-01-01

    Extrusion cooking is commonly used to produce dry pet foods. As a process involving heat treatment, extrusion cooking can have both beneficial and detrimental effects on the nutritional quality of the product. Desirable effects of extrusion comprise increase in palatability, destruction of undesirab

  12. Preparation of AZ91D magnesium alloy semi-solid billet by new strain induced melt activated method

    Institute of Scientific and Technical Information of China (English)

    JIANG Ju-fu; LUO Shou-jing; ZOU Jing-xiang

    2006-01-01

    New strain induced melt activated (new SIMA) method for preparing AZ91D magnesium alloy semi-solid billet is introduced by applying equal channel angular extrusion into strain induced step in SIMA method, by which semi-solid billet with fine spheroidal grains and average grain size of 18 μm can be prepared. Furthermore, average grain size of semi-solid billet is reduced with increasing extrusion pass of AZ91D magnesium alloy obtained in ECAE process. By using semi-solid billet prepared by new SIMA, thixoforged magazine plates component with high mechanical properties such as yield strength of 201.4 MPa, ultimate tensile strength of 321.8 MPa and elongation of 15.3%, can be obtained.

  13. Numerical simulation of the bulk forming processes for 1345 aluminum alloy billets

    Directory of Open Access Journals (Sweden)

    Fakhreddine. KHEROUF

    2015-08-01

    Full Text Available This paper presents an improved numerical simulation of bulk metal forming processes. It takes into the account the advanced formalism of large displacements and large deformations. Also, the interface workpiece formalism in considered. Metallographic studies are conducted to determine the evolution of the micro hardness as a function of annealing time and that to characterize accurately the plastic range of aluminum alloy for a range of plasticity 120%. The obtained results of metallographic studies are used to simulate a hot upsetting under the friction law of the plastic wave. Several simulations of forging operations of an axisymmetric billet by a rigid axisymmetric conical tool are performed with ABAQUS/standard computer code and that for preheated billets from 20 °C to 500 °C. The numerical study of the evolution of the normal stress at the interface has shown that the latter is independent of the tool roughness for a temperature close to 500 °C. The numerical study also allowed us to define the three areas of forging whatever cold; warm and hot forging. The effects of friction coefficient on the metal flow and contact pressure are numerically explored.

  14. Study on Fabrication of AA4032/AA6069 Cladding Billet Using Direct Chill Casting Process

    Science.gov (United States)

    Han, Xing; Zhang, Haitao; Shao, Bo; Li, Lei; Liu, Xuan; Cui, Jianzhong

    2016-04-01

    AA4032/AA6069 cladding billet in size of φ130 mm/φ110 mm was prepared by the modified direct chill casting process, and the parametric effect on casting performance was investigated using numerical simulation. Microstructures, elements distribution, and mechanical properties of the bonding interface were examined. The results show that metallurgical bonding interface can be obtained with the optimal parameters: the casting speed of 130 to 140 mm/min, the internal liquid level height of 50 to 60 mm, and the contact height of 40 to 50 mm. The metallurgical bonding interface is free of any discontinuities due to the fact that the alloying elements diffused across the interface and formed Ni-containing phase. Tensile strength of the cladding billet reaches 225.3 MPa, and the fracture position was located in AA6069 side, suggesting that the interface bonding strength is higher than the strength of AA6069. The interfacial shearing strength is 159.3 MPa, indicating excellent metallurgical bonding.

  15. Hydrodynamic modelling of hydrostatic magnesium extrusion

    NARCIS (Netherlands)

    Moodij, E.; Rooij, de M.B.; Schipper, D.J.

    2006-01-01

    Wilson’s hydrodynamic model of the hydrostatic extrusion process is extended to meet the geometry found on residual billets. The transition from inlet to work zone of the process is not considered sharp as in the model of Wilson but as a rounded edge, modelled by a parabolic function. It is shown th

  16. Extrusion and Extruded Products: Changes in Quality Attributes as Affected by Extrusion Process Parameters: A Review.

    Science.gov (United States)

    Alam, M S; Kaur, Jasmeen; Khaira, Harjot; Gupta, Kalika

    2016-01-01

    Extrusion of foods is an emerging technology for the food industries to process and market a large number of products of varying size, shape, texture, and taste. Extrusion cooking technology has led to production of wide variety of products like pasta, breakfast cereals, bread crumbs, biscuits, crackers, croutons, baby foods, snack foods, confectionery items, chewing gum, texturized vegetable protein (TVP), modified starch, pet foods, dried soups, dry beverage mixes etc. The functional properties of extruded foods plays an important role for their acceptability which include water absorption, water solubility, oil absorption indexes, expansion index, bulk density and viscosity of the dough. The aim of this review is to give the detailed outlines about the potential of extrusion technology in development of different types of products and the role of extrusion-operating conditions and their effect on product development resulting in quality changes i.e physical, chemical, and nutritional, experienced during the extrusion process. PMID:25574813

  17. Extrusion Die Design and Process Simulation of High Strength Aluminium Alloy

    Science.gov (United States)

    Sheu, Jinn-Jong; Chen, Yan-Hong; Su, Guan-Cheng

    2011-01-01

    Aluminium alloy 7075 is an excellent metal with the features of high strength and light weight. The solid extruded parts of AL 7075 are commonly used in the structure members of airplanes and bicycles. The seamless tubes of AL 7075 are also used, while tubes with welding line (seamed) are mainly made by the other types of aluminium alloy. This research is focused on the extrusion die design and process simulation of the rectangular seamed AL 7075 tubes. A new die design concept is proposed to increase the welding pressure in the chamber to solve the problem of poor welding ability of AL 7075. The key points of welding ability improvement are the higher welding pressure, the crucial billet temperature, and the extrusion speed. The designed extrusion die should have some features to control the material flow and achieve the higher welding pressure. In this paper, not only use the traditional die bearing and the welding chamber, but also add a conical guiding chamber (specified with chamber height and width) to improve the material flow control. Finite element method is used to simulate the extrusion process and evaluate the effect of die design parameters for a seamed rectangular 7075 tube extrusion. The die stress should be considered carefully because of increasing the welding pressure also increases the die stress. Taguchi method is used to obtain the optimum combination of die design parameters to get higher welding pressure and keep the die stress at a reasonable low level. The method proposed in this paper is able to increase the welding pressure with the cost of reasonable die stress.

  18. Analysis of the Alternate Extrusion and Multiaxial Compression Process

    Directory of Open Access Journals (Sweden)

    Kwapisz M.

    2015-04-01

    Full Text Available The paper present the results of numerical simulations of the alternate indirect extrusion and multiaxial compression process, performed using commercial software designed for the thermomechanical analysis of plastic working processes, Forge 2009. The novel method of alternate indirect extrusion and multiaxial compression, proposed by the authors, is characterized by the occurrence of strain states in the material being plastically worked, which are similar to those occurring in the equal channel angular pressing and cyclic extrusion compression processes.

  19. Effect of extrusion wheel angular velocity on continuous extrusion forming process of copper concave bus bar

    Institute of Scientific and Technical Information of China (English)

    WU Peng-yue; XIE Shui-sheng; LI Hua-qing; YAN Ming; HUANG Guo-jie; CHENG Lei

    2007-01-01

    The continuous extrusion forming process for producing large section copper concave bus bar under different extrusion wheel angular velocities was studied by three-dimensional finite element technology based on software DEFORM-3D. The rigid-viscoplastic constitutive equation was employed in the model. The numerical simulation results show that the deformation body flow velocity in the die orifice increases gradually with the increase of the extrusion wheel angular velocity. But slippage between the rod and extrusion wheel occurs when the extrusion wheel angular velocity is high. The effective stress near the die orifice enhances gradually with increasing extrusion wheel angular velocity. High stress is concentrated in adjacent regions of the flash gap. The effective strain gradient is greater near the abutment than that near the die orifice. The effective strain of the product increases gradually with increasing extrusion wheel angular velocity. In the deformation process, the deformation body temperature increases remarkably due to friction and deformation. So the cooling is necessary in the region of the die and tools.

  20. Improvement of Dissolution Behavior for Poorly Water-Soluble Drug by Application of Cyclodextrin in Extrusion Process: Comparison between Melt Extrusion and Wet Extrusion

    OpenAIRE

    Yano, Hideki; Kleinebudde, Peter

    2010-01-01

    The purpose of this study was to improve dissolution behavior of poorly water-soluble drugs by application of cyclodextrin in extrusion processes, which were melt extrusion process and wet extrusion process. Indomethacin (IM) was employed as a model drug. Extrudates containing IM and 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) in 1:1 w/w ratio were manufactured by both melt extrusion process and wet extrusion process. In vitro drug release properties of IM from extrudates and physiochemical pro...

  1. Hydrodynamic Analysis to Process of Hydrostatic Extrusion for Tungsten Alloy

    Institute of Scientific and Technical Information of China (English)

    Fuchi WANG; Zhaohui ZHANG; Shukui LI

    2001-01-01

    The hydrodynamic analysis to the process of the hydrostatic extrusion for tungsten alloy is carried through the hydrodynamic lubrication theory and Reynolds equation in this paper. The critical velocity equation when the hydrodynamic lubrication conditions appear between the surfaces of the work- piece and the die is obtained, and the relationship between the critical velocity and the extrusion parameters is discussed, which build the theoretical bases to the application of the hydrostatic extrusion for tungsten alloy.

  2. MODERNIZATION OF TECHNOLOGICAL LINE FOR CELLULAR EXTRUSION PROCESS

    Directory of Open Access Journals (Sweden)

    Tomasz Garbacz

    2014-06-01

    As part of the modernization of the cellular extrusion technology the extrusion head was designed and made. During the designing and modeling of the head the Auto CAD programe was used. After the prototyping the extrusion head was tested. In the article specification of cellular extrusion process of thermoplastics was presented. In the research, the endothermal chemical blowing agents in amount 1,0% by mass were used. The quantity of used blowing agent has a direct influence on density and structure of the extruded product of modified polymers. However, these properties have further influence on porosity, impact strength, hardness, tensile strength and another.

  3. Rheologic behaviors of A356 aluminum alloy billet produced by semisolid continuous casting process

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The experiments for rheologic behaviors of semisolid continuous casting billets of A356 alloy in semisolid state had been carried out with a rnultifunctional rheometer. The results show that the deformation rate increases with loading time, the maximum strain reaches to 120 % ( which is one time larger than that of traditional mold casting billet) and the strain can be rapidly elirninated to 10% after unloading. Moreover, there is a critic stress for billet deformation even in semisolid state, which is named as critic shear stress. This stress increases with the decreasing of heating time. The rheologic behaviors can be expressed by five elements mechanical model (H2 - [N1 | H2] - [N2|S] ) and can be modified with the increasing of heating time.

  4. Heat Treated AZ61 Magnesium Alloy Obtained by Direct Extrusion and Continuous Rotary Extrusion Process

    Directory of Open Access Journals (Sweden)

    Bigaj M.

    2016-03-01

    Full Text Available The results of studies carried out on the heat treated AZ61 magnesium alloy extruded by two methods, i.e. direct extrusion and continuous rotary extrusion, were presented. As part of the work, parameters of the T6 heat treatment were proposed and aging curves were plotted. The solution heat treatment process was accompanied by the grain growth. During artificial aging, due to the decomposition of solid solution, the β-Mg17Al12 phase was precipitated from the supersaturated α solution. It precipitated in a coagulated form at the grain boundaries and in the form of fine-dispersed plates arranged in a preferred direction relative to the grain orientation. Rods obtained by continuous rotary extrusion, unlike those made by the direct process, exhibited a low degree of texturing and lack of anisotropic properties.

  5. Role of lipids in the extrusion cooking processes

    OpenAIRE

    Berghofe, E.; Schoenlechner, Regine; Ilo, S.

    2000-01-01

    Extrusion is a versatile and very efficient technology that is widely used in food and feed processing. The cooking extruders have found many applications, which include: breakfast cereals, snack foods, other cereal based products, pet food and aquatic foods, texturized vegetable proteins, confectionery products, chemical and biochemical reactions, and oil extraction. Lipids are components that play an important role in most of the extrusion cooking processes. They can act as plastificizers o...

  6. Analysis of the Alternate Extrusion and Multiaxial Compression Process

    OpenAIRE

    Kwapisz M.; Knapiński M.; Dyja H.; Kawałek A.

    2015-01-01

    The paper present the results of numerical simulations of the alternate indirect extrusion and multiaxial compression process, performed using commercial software designed for the thermomechanical analysis of plastic working processes, Forge 2009. The novel method of alternate indirect extrusion and multiaxial compression, proposed by the authors, is characterized by the occurrence of strain states in the material being plastically worked, which are similar to those occurring in the equal cha...

  7. A new engineering model for understanding extrusion process

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    A new engineering method is proposed to understand extrudate expansion and extrusion operation parameters for starch based food extrusion cooking process through dimensional analysis principle, i.e. Buckingham pi theorem. Three dimensionless groups, i.e. pump efficiency, water content...... and temperature, are suggested to describe the extrudate expansion. Using the three dimensionless groups, an equation is derived to express the extrudate expansion. The model has been used to correlate the experimental data for whole wheat flour and fish feed extrusion cooking. The average deviations...

  8. Finite element simulation of extrusion of optical fiber preforms: Effects of wall slip

    Science.gov (United States)

    Zhang, Zhi Feng; Zhang, Yilei

    2016-03-01

    Extrusion has been successfully used to fabricate optical fiber preforms, especially microstructured ones. Although simplified mathematical model has been used to calculate the extrusion pressure or speed, more frequently die design and extrusion process optimization depend on trial and error, which is especially true for complex die and preform design. This paper employs the finite element method (FEM) to simulate the billet extrusion process to investigate the relationship between the extruding pressure, the billet viscosity, the wall slip condition and the extruding speed for extrusion of rod preforms. The slipping wall boundary condition is taken into account of the finite element model, and the simulated extruding pressure agrees with the one experimental value reported preciously. Then the dependence of the extruding speed on the extruding pressure, billet viscosity and the slip speed is systematically simulated. Simulated data is fitted to a second order polynomial model to describe their relationship, and the terms of the model are reduced from nine to five by using a statistical method while maintaining the fitting accuracy. The FEM simulation and the fitted model provide a convenient and dependable way to calculate the extrusion pressure, speed or other process parameters, which could be used to guide experimental design for future preform extrusion. Furthermore, the same simulation could be used to optimize die design and extrusion process to improve quality of extruded preforms.

  9. Multiple direct extrusion: A new technique in grain refinement

    Energy Technology Data Exchange (ETDEWEB)

    Zaharia, L.; Chelariu, R. [' Gheorghe Asachi' Technical University of Iasi, Faculty of Materials Science and Engineering, D. Mangeron 61A, 700050 Iasi (Romania); Comaneci, R., E-mail: amvric@yahoo.com [' Gheorghe Asachi' Technical University of Iasi, Faculty of Materials Science and Engineering, D. Mangeron 61A, 700050 Iasi (Romania)

    2012-07-30

    Highlights: Black-Right-Pointing-Pointer A new method for grain refinement was applied at room temperature on copper. Black-Right-Pointing-Pointer A possible grain fragmentation mechanism was analyzed. Black-Right-Pointing-Pointer Square bars with uniform microstructure and mechanical properties were obtained. Black-Right-Pointing-Pointer The microstructure and mechanical properties evolution during MDE was studied. - Abstract: A novel high-straining bulk deformation technique based on repeating conventional direct extrusion is presented. This technique, named multiple direct extrusion (MDE), uses a square container with a rectangular die aperture that can achieve a minimum 50% reduction/pass in the cross section of the billet. After extrusion, the new billet is cut perpendicular to the longitudinal axis. The resulting halves are then joined to obtain a square shape again so that the direct extrusion process can be repeated. Two processing routes are possible before reintroducing the billet into the container: no rotation and 90 Degree-Sign rotation around the longitudinal axis. During each cycle, the billets change their geometrical shape and as a result, the cross section area gets smaller. A mechanism of grain fragmentation during MDE based on the analysis of velocity discontinuities along slip lines in the deformation zone is suggested. Four cycles of MDE were applied to commercial copper and the potential for grain refinement, and the improvement in mechanical properties were evaluated.

  10. Continuous extrusion and rolling forming of copper strips

    Directory of Open Access Journals (Sweden)

    Yun Xinbing

    2016-01-01

    Full Text Available Continuous extrusion and rolling technology was proposed as a new strip production technology. It conducts a hot rolling process using waste heat after continuous extrusion. The continuous extrusion and rolling forming was simulated with DEFORM-3DT. Influences of extrusion wheel velocity and rolling reduction on the continuous extrusion and rolling forming were analyzed. It was shown that as extrusion wheel velocity increases, torque of extrusion wheel, chamber force and rolling force, will drop; temperature of the billet in the area of abutment which is highest will increase. As the rolling reduction is increased, torque of the extrusion wheel and force acting on the chamber decrease, while torque and force of the rolls increase. The experimental results showed that a homogeneously distributed and equiaxed grains microstructure can be formed in copper strip billets with an average grain size of about 80 μm, after continuous extrusion. Grains of the copper strips are stretched clearly, during rolling, along the rolling direction, to form a stable orientation. Nevertheless, the grain boundaries are still relatively clear to see.

  11. STRAIN ANALYSIS OF LATERAL EXTRUSION PROCESS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The strain distribution of equal-cross section lateral extrusion(ECSLE) has been simulated by finite element method. Considering the effect of friction and the width of sample, the simulation results are very close to the reality. The simulated results showed that, around the corner of die, the strain is distributed by sharp layers, and the gradient of the layers is very large, which means that the deformation is just plane shear deformation; the larger the width of sample or the smaller the friction, the more uniform the strain distribution is.

  12. FEM and FVM compound numerical simulation of aluminum extrusion processes

    Institute of Scientific and Technical Information of China (English)

    周飞; 苏丹; 彭颖红; 阮雪榆

    2003-01-01

    The finite element method (FEM) and the finite volume method (FVM) numerical simulation methods have been widely used in forging industries to improve the quality of products and reduce the costs. Because of very concentrative large deformation during the aluminum extrusion processes, it is very difficult to simulate the whole forming process only by using either FEM or FVM. In order to solve this problem, an FEM and FVM compound simulation method was proposed. The theoretical equations of the compound simulation method were given and the key techniques were studied. Then, the configuration of the compound simulation system was established. The tube extrusion process was simulated successfully so as to prove the validity of this approach for aluminum extrusion processes.

  13. Microstructure and properties of AZ80 magnesium alloy prepared by hot extrusion from recycled machined chips

    Institute of Scientific and Technical Information of China (English)

    刘英; 李元元; 张大童; 倪东惠; 陈维平

    2002-01-01

    AZ80 magnesium alloy was prepared by hot extrusion of recycled machined chips and its microstructure and mechanical properties were investigated. Hot pressing was employed to prepare extrusion billets of AZ80 chips, then the billets were hot extruded at 623K with an extrusion ratio of 25∶ 1. The extruded rods show a high ultimate tensile strength of 285MPa and a high elongation of 6%. Due to grain refinement by extrusion, mechanical properties of the extruded rods are much higher than those of as-cast AZ80 alloy. Process technique and chips densification mechanism were also studied. Results show that hot extrusion is an efficient method for AZ80 alloy chips recycling.

  14. Dynamic globularization prediction during cogging process of large size TC11 titanium alloy billet with lamellar structure

    Directory of Open Access Journals (Sweden)

    Hong-wu Song

    2014-03-01

    Full Text Available The flow behavior and dynamic globularization of TC11 titanium alloy during subtransus deformation are investigated through hot compression tests. A constitutive model is established based on physical-based hardening model and phenomenological softening model. And based on the recrystallization mechanisms of globularization, the Avrami type kinetics model is established for prediction of globularization fraction and globularized grain size under large strain subtransus deformation of TC11 alloy. As the preliminary application of the previous results, the cogging process of large size TC11 alloy billet is simulated. Based on subroutine development of the DEFORM software, the coupled simulation of one fire cogging process is developed. It shows that the predicted results are in good agreement with the experimental results in forging load and microstructure characteristic, which validates the reliability of the developed FEM subroutine models.

  15. 钢丝缠绕黑色金属挤压筒的设计%Design of Steel Wire Wound Extrusion Containers for Steel Hot Extrusion Process

    Institute of Scientific and Technical Information of China (English)

    刘长勇; 张磊; 林峰; 张人佶; 颜永年; 康飞宇

    2013-01-01

    挤压筒是大口径厚壁无缝钢管热挤压工艺中最为重要的模具,传统的多层组合挤压筒设计方法面临很大挑战.提出采用钢丝缠绕预紧挤压筒的方案,由于钢丝在高温下存在蠕变加速和应力松弛,将钢丝缠绕技术应用于挤压筒的最大问题是解决挤压筒预热与钢丝防护之间的矛盾.针对此矛盾,分析钢丝缠绕挤压筒设计中的关键问题包括预热、钢丝防护和预应力分布控制,提出高温钢锭内置预热和电加热预热两种设计方案,分别分析两种设计方案存在的问题、解决方法和优缺点.针对电加热预热挤压筒,提出新型的热致预应力方法来产生预紧力,将内衬和中衬预热至350℃以上,中衬和外衬之间设有隔热层,经隔热后外衬和钢丝层温度低于80℃,利用两者之间温度差而导致的热膨胀量差值来产生预紧力.基于此想法,设计制造内直径170 mm的挤压筒原理样件,通过温度测试和应力测试,表明所提出的电加热预热挤压筒可达到预期的预紧效果,为挤压筒的设计探讨一种新型的设计方法.%Extrusion container is the most important tooling in large steel tube extrusion process. Traditional design approaches such as multi-layered extrusion container would meet great challenges for large extrusion container. Steel wire wound extrusion is proposed. Due to accelerated creep behavior and stress relaxation of steel wire under high temperature, the primary difficulty of applying steel wire winding to the design of extrusion container is to solve the conflict between preheating and protection of the wire from high temperature. The key problems of wire wound containers including preheating, steel wire protection and control of prestress distribution are analyzed. Two solutions to preheating are proposed including hot billet preheating and electrical heating rods. The problems, solutions, advantages and disadvantages are discussed respectively. A

  16. Effects of process parameters and die geometry on longitudinal welds quality in aluminum porthole die extrusion process

    Institute of Scientific and Technical Information of China (English)

    LIU Jian; LIN Gao-yong; FENG Di; ZOU Yan-ming; SUN Li-ping

    2010-01-01

    By using the rigid-visco-plasticity finite element method,the welding process of aluminum porthole die extrusion to form a tube was simulated based on Deform-3D software.The welding chamber height(H),back dimension of die leg(D),process velocity and initial billet temperature were used in FE simulations so as to determine the conditions in which better longitudinal welding quality can be obtained.According to K criterion,the local welding parameters such as welding pressure,effective stress and welding path length on the welding plane are linked to longitudinal welds quality.Simulation turns out that pressure-to-effective stress ratio(p/σ)and welding path length(L)are the key factors affecting the welding quality.Higher welding chamber best and sharper die leg give better welding quality.When H=10 mm and D=0.4 mm,the longitudinal welds have the best quality.Higher process velocity decreases welds quality.The proper velocity is 10 mm/s for this simulation.In a certain range,higher temperature is beneficial to the longitudinal welds.It is found that both 450 and 465℃ can satisfy the requirements of the longitudinal welds.

  17. Extrusion process optimization for toughness in balloon films

    Science.gov (United States)

    Cantor, K. M.; Harrison, I. R.

    1993-01-01

    An experimental optimization process for blown film extrusion is described and examined in terms of the effects of the technique on the toughness of balloon films. The optimization technique by Cantor (1990) is employed which involves the identification of key process variables including screw speed, nip speed, bubble diameter, and frost-line height for analysis to optimize the merit function. The procedure is employed in the extrusion of a low-density polyethylene polymer, and the resulting optimized materials are toughness- and puncture-tested. Balloon toughness is optimized in the analytical relationship, and the process parameters are modified to attain optimal toughness. The film produced is shown to have an average toughness of 24.5 MPa which is a good value for this key property of balloon materials for high-altitude flights.

  18. Effect of die shape on the metal flow pattern during direct extrusion process

    Directory of Open Access Journals (Sweden)

    Solomon, N.

    2010-10-01

    Full Text Available The geometric shape of the tools is the main factor by which an optimum technological process can be developed. In the case of extrusion process the strain distribution and other important variables that influence material structure, such as hydrostatic stress, are strongly dependent on the geometry of the die. Careful design of the extrusion die profile can therefore control the product structure and can be used to minimise the amount of inhomogeneity imparted into the product. A possibility to minimise the amount of product inhomogeneity is the using of a flat die with a fillet radius in front to the bearing surface with leads to a minimum dead zone and consequently to a minimum friction at billet-container interface. In the case of aluminium alloy type 2024, for an extrusion ratio of R=8.5, good results were obtained with a fillet radius of 3.0 mm. The experimental data have been used for the finite element numerical simulation of the extrusion process. The data obtained by numerical simulation with FORGE2 programme confirm the theoretical and experimental outcomes. The aim of this paper is to study the influence of such flat die on the material flow during direct extrusion process and consequently on extruded product microstructure and mechanical properties.La forma geométrica de las herramientas es el principal factor a través del cual un proceso óptimo de deformación plástica puede ser mejor desarrollado. En el caso del proceso de extrusión, la distribución de la deformación y otras variables importantes, como la presión hidrostática, que pueden influir en la estructura del material, son fuertemente dependientes de la geometría del molde. Mediante un diseño apropiado del perfil del molde de extrusión se pueden controlar la estructura y las propiedades mecánicas del producto y, por lo tanto, se puede utilizar para minimizar la cantidad de la no homogeneidad del producto. Una posibilidad para reducir al mínimo la cantidad de

  19. Microstructure and mechanical properties of AZ31 Mg alloy processed by high ratio extrusion

    Institute of Scientific and Technical Information of China (English)

    CHEN Yong-jun; WANG Qu-dong; LIN Jin-bao; ZHANG Lu-jun; ZHAI Chun-quan

    2006-01-01

    The microstructure and mechanical properties of AZ31 Mg alloy processed by high ratio extrusion (HRE) were investigated. General extrusion with extrusion ratio of 7 and high ratio extrusion with extrusion ratio 100 were contrastively conducted at 250, 300 and 350 ℃. The results show that HRE process may be applied successfully to AZ31 Mg alloy at temperatures of 250, 300 and 350 ℃ and this leads to obvious grain refinement during HRE process. The strength of HRE process is improved obviously compared with that of general extrusion. The grain refining mechanism of HRE process was also discussed. The current results imply that the simple high ratio extrusion method might be a feasible and effective processing means for refining the microstructure and improving the mechanical properties of AZ31 Mg alloy.

  20. An improved billet on billet extrusion process of continuous aluminium alloy shapes for cryogenic applications in the Compact Muon Solenoid experiment

    CERN Document Server

    Tavares, S S

    2003-01-01

    The Compact Muon Solenoid (CMS) is one of the experiments being designed in the framework of the Large Hadron Collider accelerator at CERN. CMS will contain the largest and the most powerful superconducting solenoid magnet ever built in terms of stored energy. It will work at 4.2 K, will have a magnetic length of 12.5 m, with a free bore of 6m and will be manufactured as a layered and modular structure of NbTi cables embedded in a high purity (99.998%) Al- stabiliser. Each layer consists of a wound continuous length of 2.55 km. In order to withstand the high electromagnetic forces, two external aluminium alloy reinforcing sections are foreseen. These reinforcements, of 24 mm multiplied by 18 mm cross-section, will be continuously electron beam (EB) welded to the pure Al-stabiliser. The alloy EN AW-6082 has been selected for the reinforcements due to its excellent extrudability, high strength in the precipitation hardened state, high toughness and strength at cryogenic temperatures and ready EB weldability. Ea...

  1. Pellet manufacturing by extrusion-spheronization using process analytical technology

    DEFF Research Database (Denmark)

    Sandler, Niklas; Rantanen, Jukka; Heinämäki, Jyrki;

    2005-01-01

    The aim of this study was to investigate the phase transitions occurring in nitrofurantoin and theophylline formulations during pelletization by extrusion-spheronization. An at-line process analytical technology (PAT) approach was used to increase the understanding of the solid-state behavior...... hydrate (nitrofurantoin), dehydration was observed at higher temperatures. To reach an understanding of the process and to find the critical process parameters, the use of complementary analytical techniques are absolutely necessary when signals from APIs and different excipients overlap each other....

  2. Semi-solid extrusion of aluminum alloy ZL116

    Institute of Scientific and Technical Information of China (English)

    Zhao Dazhi; Lu Guimin; Cui Jianzhong

    2008-01-01

    The semi-solid forward-extruding feasibility of reheated ZL116 alloy cast by the near-liquidus semicontinuous casting process was studied by analyzing the microstructures and properties of forward-extruded bars.The results show that the microstructure of the ZL116 alloy billets cast by near-liquidus semi-continuous casting is mainly made up of homogeneous,fine global-or rosette-shaped grains.The microstructure of the billets,reheated and held at 575℃,contains stable and net-spherical grains which are suitable for semi-solid thixoformina.The semi-solid forward-extruded bars of the ZL116 alloy billet are facially smooth.microstructurally fine and homogeneous.Therefore the feasibility of semi-solid foFward-extrusion of ZL116 alloy is thus excellent.

  3. Interim report on concreted uranium fines and chips billet curing tests: a basis for resuming shipment of concreted uranium scrap billets

    International Nuclear Information System (INIS)

    Through extensive testing and analyses of the concretion process, billets and shipping conditions, it has been determined that properly cured concreted billets can be safely shipped to National Lead Company of Ohio (NLO), Fernald. During curing, billets will be dried for 26 days prior to shipment with the last 10 days between 54 to 660C (130 to 1500F). Such dried billets can withstand temperatures up to 850C (1850F). The maximum billet temperature that can be expected to occur in shipment is 500C (1230F). Thus, the drying cycle becomes a burning test at temperatures which the billets will not reach during shipment to NLO

  4. Impact of processing prior to thermomechanical extrusion of starchy materials

    OpenAIRE

    Lopez, Linda

    2003-01-01

    Dry pet foods are composed of cereal, proteins, fats, fibres and other minor components. The manufacturing process comprises a first step where the dry ingredients are ground to a suitable particle size and blended, a second step where the dry powder is mixed with water and steam in a preconditioner and then extruded and a final step where the product is dried and coated. The aim of this work was to study the effects of the unit operations prior to thermos mechanical extrusion in the dry p...

  5. Role of lipids in the extrusion cooking processes

    Directory of Open Access Journals (Sweden)

    Berghofe, E.

    2000-04-01

    Full Text Available Extrusion is a versatile and very efficient technology that is widely used in food and feed processing. The cooking extruders have found many applications, which include: breakfast cereals, snack foods, other cereal based products, pet food and aquatic foods, texturized vegetable proteins, confectionery products, chemical and biochemical reactions, and oil extraction. Lipids are components that play an important role in most of the extrusion cooking processes. They can act as plastificizers or emulsifiers, and affect more significantly texture and stickiness of the extrudate. This paper reviews effect of oils and other lipids reactions during extrusion cooking as well as the effects of amylase-lipid complexation on extrudate quality.La extrusión es, en general, una tecnología versátil y muy eficiente, que se aplica ampliamente en la elaboración de alimentos y piensos. Los equipos de cocción-extrusión tienen numerosas aplicaciones, entre las que pueden incluirse: los cereales de desayuno listos para comer, los aperitivos, diferentes productos basados en cereales, los piensos para animales domésticos y peces, proteínas vegetales texturizadas, productos de pastelería, reacciones químicas y bioquímicas, y la extracción de aceites. Los lípidos son componentes que juegan un papel importante en la mayoría de los procesos de cocción-extrusión. Pueden actuar como plastificantes o como emulsionantes, suministrando lubricación. En este artículo se revisan con detalle los efectos de las reacciones de los aceites y otros lípidos durante el proceso de cocción-extrucción así como el efecto de la formación de complejos amilasa-lípidos sobre la calidad de los extrudados.

  6. The Effects of Process Parameters on Evolutions of Thermodynamics and Microstructures for Composite Extrusion of Magnesium Alloy

    OpenAIRE

    H.-J. Hu

    2013-01-01

    To research the effects of process parameters on evolutions of extrusion force and temperature rise and microstructures for composite extrusion of magnesium alloy which includes initial extrusion and shearing process subsequently and is shortened for “ES” in this paper, the ES extrusion process has been researched by using finite element modeling (FEM) technology. The rules of temperature rise and the extrusion force varying with process parameters have been developed. The thermal-mechanical ...

  7. Feed extrusion process description Descrição do processo de extrusão do alimento

    Directory of Open Access Journals (Sweden)

    Galen J. Rokey

    2010-07-01

    Full Text Available The following work discusses the main features of feed extrusion process explaining the expected effects on the final product according to the raw material used as starch, protein, fat and fiber. The selection of processing equipments as feeder, preconditioner and extruder is discussed considering the involved costs and the probability of future expansion. Dryers are also essential in the extrusion process as it reduces the level of moisture in an extrusion cooked product. High moisture levels increase the water activity which favors the bacterial and mold growth so an overview of different kinds of dryers is considered. Guidelines for an economic prediction are shown to determine the potential for profit considering the input of raw material cost, energy cost and capital equipment cost as related to the extrusion module.Este trabalho aborda as principais características do processo de extrusão de alimentos, explicando os efeitos esperados no produto final, em função do tipo de componente utilizado na receita, como amido, proteínas, gorduras e fibras. O dimensionamento dos equipamentos da linha de extrusão, como silo, pré-condicionador e extrusor, é tratado considerando-se os custos envolvidos e a possibilidade de expansões futuras. Secadores também são essenciais no processo de extrusão, pois reduzem o nível de umidade do produto final. Altos níveis de umidade aumentam a atividade de água, favorecendo a proliferação de bactérias e mofo, portanto, uma visão geral de diferentes tipos de secadores é considerada. Orientações para uma previsão econômica são apresentadas para se determinar o potencial de lucro, considerando-se os custos com a matéria-prima, a energia utilizada no processo de fabricação e os equipamentos relacionados ao módulo de extrusão.

  8. Optimization of extrusion process for production of nutritious pellets

    Directory of Open Access Journals (Sweden)

    Ernesto Aguilar-Palazuelos

    2012-03-01

    Full Text Available A blend of 50% Potato Starch (PS, 35% Quality Protein Maize (QPM, and 15% Soybean Meal (SM were used in the preparation of expanded pellets utilizing a laboratory extruder with a 1.5 × 20.0 × 100.0 mm die-nozzle. The independent variables analyzed were Barrel Temperature (BT (75-140 °C and Feed Moisture (FM (16-30%. The effect of extrusion variables was investigated in terms of Expansion Index (EI, apparent density (ApD, Penetration Force (PF and Specific Mechanical Energy (SME, viscosity profiles, DSC, crystallinity by X-ray diffraction, and Scanning Electronic Microscopy (SEM. The PF decreased from 30 to 4 kgf with the increase of both independent variables (BT and FM. SME was affected only by FM, and decreased with the increase in this variable. The optimal region showed that the maximum EI was found for BT in the range of 123-140 °C and 27-31% for FM, respectively. The extruded pellets obtained from the optimal processing region were probably not completely degraded, as shown in the structural characterization. Acceptable expanded pellets could be produced using a blend of PS, QPM, and SM by extrusion cooking.

  9. The positioning algorithm based on feature variance of billet character

    Science.gov (United States)

    Yi, Jiansong; Hong, Hanyu; Shi, Yu; Chen, Hongyang

    2015-12-01

    In the process of steel billets recognition on the production line, the key problem is how to determine the position of the billet from complex scenes. To solve this problem, this paper presents a positioning algorithm based on the feature variance of billet character. Using the largest intra-cluster variance recursive method based on multilevel filtering, the billet characters are segmented completely from the complex scenes. There are three rows of characters on each steel billet, we are able to determine whether the connected regions, which satisfy the condition of the feature variance, are on a straight line. Then we can accurately locate the steel billet. The experimental results demonstrated that the proposed method in this paper is competitive to other methods in positioning the characters and it also reduce the running time. The algorithm can provide a better basis for the character recognition.

  10. Visualization of the Crystallization in Foam Extrusion Process

    Science.gov (United States)

    Tabatabaei Naeini, Alireza

    In this study, crystal formation of polypropylene (PP) and poly lactic acid (PLA) in the presence of CO2 in foam extrusion process was investigated using a visualization chamber and a CCD camera. The role of pre-existing crystals on the foaming behavior of PP and PLA were studied by characterizing the foam morphology. Visualization results showed that crystals formed within the die before foaming and these crystals affect the cell nucleation behavior and expansion ratio of PP and PLA significantly. Due to the fast crystallization kinetics of PP, crystallinity should be optimum to achieve uniform cell structure with high cell density and high expansion ratio. In PLA, enhancement of crystallinity is crucial for getting foam with a high expansion ratio. It was also visualized that CO2 significantly suppresses the crystallization temperature in PP through the plasticization effect as well as its influence on flow induced crystallinity.

  11. SUPERCRITICAL CO2 EXTRUSION – OPPORTUNITIES FOR FOOD AND BIOLOGICAL PROCESSING

    Science.gov (United States)

    Extrusion cooking is a high temperature, short time processing method. During extrusion processing, many chemical and structural changes of the feed materials occur inside the barrel due to high temperatures, shear rates, and pressures. These alterations affect bonding between molecules, which in...

  12. Raw material changes and their processing parameters in an extrusion cooking process

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    In this work, the effects of raw material and process parameters on product expansion in a fish feed extrusion process were investigated. Four different recipes were studied with a pilot-scale twin-screw co-rotating extruder according to a set of pre-defined processing conditions. In the four...

  13. Parametric Optimization of Simulated Extrusion of Square to Square Section Through Linear Converging Die

    Science.gov (United States)

    Mohapatra, S. K.; Maity, K. P.

    2016-02-01

    The effect of various process parameters for determining extrusion load has been studied for square to square extrusion of Al-6061 alloy, a most used aluminium alloy series in forming industries. Parameters like operating temperature, friction condition, ram velocity, extrusion ratio and die length have been chosen as an input variable for the above study. Twenty five combinations of parameters were set for the investigation by considering aforementioned five parameters in five levels. The simulations have been carried out by Deform-3D software for predicting maximum load requirement for the complete extrusion process. Effective stress and strain distribution across the billet has been checked. Operating temperature, extrusion ratio, friction factor, ram velocity and die length have the significant effect in decreasing order on the maximum load requirement.

  14. Simulation of a combustion process of a billet reheating furnace; Simulacao do processo de combustao de um forno de reaquecimento de tarugos

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Eduardo Sergio da Silva; Barros, Jose Eduardo Mautone [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecanica; Ribeiro, Vicente Aleixo Pinheiro [ArcelorMittal Monlevade, Serra, ES (Brazil); Moura Junior, Jose dos Reis Vieira de [ArcelorMittal Long Carbon Americas (Luxembourg); Belisario, Leandro Pego [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)

    2010-07-01

    Real data-based energy balances with few simplifications are a powerful tool for furnaces energy performance evaluation, helping technical people to guide efforts in energy consumption issues, and consequently, in a final product cost reduction. This paper presents a methodology to simulate the combustion process in several operational conditions of a walking-hearth reheat furnace for billets in rolling mill facilities. The computational model consists, basically, in a dynamical solution which measured input variables are supplied from the furnaces supervisory and compared to measures by instruments in the system. Finally, it is made a variability analysis of the furnace and heat exchangers efficiencies.. (author)

  15. Porthole Extrusion Process Design for Magnesium-Alloy Bumper Back Beam by Using FE Analysis and Extrusion Limit Diagram

    OpenAIRE

    Lee, Sung-Yun; Ko, Dae-Cheol; Lee, Sang-Kon; Lee, In-Kyu; Joeng, Myeong-Sik; Kim, Da Hye; Cho, Yong-Jae

    2014-01-01

    In recent years, several studies with focus on developing state-of-the-art manufacturing technologies have been conducted to produce light vehicles by employing parts made of light materials such as aluminum and magnesium. Of such materials, magnesium has been found to pose numerous issues, because it cannot be deformed (plastic deformation) easily at low temperatures. Furthermore, oxidation on the surface of manganese occurs at high temperatures. This study analyzes the extrusion process for...

  16. Optimizing the seamless tube extrusion process using the finite element method

    Science.gov (United States)

    Li, Feng; Li, Li; Wang, Xiang; Ma, Xu Liang

    2010-03-01

    In order to reveal the mechanism of extrusion forming for large-scale aluminum alloy seamless pipe, in this research the rigid-viscous plastic finite element method was used to analyze the effect of the technological parameters of the aluminum alloy pipe extrusion process, consistent with the use requirements.

  17. Investigation of the process energy demand in polymer extrusion: A brief review and an experimental study

    International Nuclear Information System (INIS)

    Highlights: • Energy consumption and losses in polymer extrusion are discussed. • This compares energy consumption in polymer extrusion at different conditions. • The role of power factor on energy efficiency in polymer extrusion is explored. • Empirical models on extruder energy consumption are provided. • Computer modelling of energy consumption of polymer extrusion is performed. - Abstract: Extrusion is one of the fundamental production methods in the polymer processing industry and is used in the production of a large number of commodities in a diverse industrial sector. Being an energy intensive production method, process energy efficiency is one of the major concerns and the selection of the most energy efficient processing conditions is a key to reducing operating costs. Usually, extruders consume energy through the drive motor, barrel heaters, cooling fans, cooling water pumps, gear pumps, etc. Typically the drive motor is the largest energy consuming device in an extruder while barrel/die heaters are responsible for the second largest energy demand. This study is focused on investigating the total energy demand of an extrusion plant under various processing conditions while identifying ways to optimise the energy efficiency. Initially, a review was carried out on the monitoring and modelling of the energy consumption in polymer extrusion. Also, the power factor, energy demand and losses of a typical extrusion plant were discussed in detail. The mass throughput, total energy consumption and power factor of an extruder were experimentally observed over different processing conditions and the total extruder energy demand was modelled empirically and also using a commercially available extrusion simulation software. The experimental results show that extruder energy demand is heavily coupled between the machine, material and process parameters. The total power predicted by the simulation software exhibits a lagging offset compared with the

  18. Processing and Microstructural Evolution of Superalloy Inconel 718 during Hot Tube Extrusion

    Institute of Scientific and Technical Information of China (English)

    Shihong ZHANG; Zhongtang WANG; Bing QIAO; Yi XU; Tingfeng XU

    2005-01-01

    The processing parameters of tube extrusion for superalloy Inconel 718 (IN 718), such as slug temperature, tools temperature, choice of lubricant, extrusion ratio and extrusion speed, were determined by experiment in this paper. An appropriate temperature range recommended for the slug is 1080~1120℃, and the temperature range recommended for the tools is 350~500℃. The microstructural evolution of superalloy IN 718 during tube extrusion was analyzed.With the increase of the deformation the cross crystal grains were slightly refined. While the vertical crystal grain is elongated evidently and the tensile strength increased along the axial rake. Glass lubricants have to be spread on the slug surface after being heated to 150~200℃, vegetable oil or animal oil can be used as the lubricant on the surface of the tools to reduce the extrusion force remarkably.

  19. Estimation of the hot extrusion process pressure cycle of zircaloy tubes by torsion and compression tests

    International Nuclear Information System (INIS)

    In the production of Zircaloy-4 tubes for nuclear reactors, the first semi-processed tubular form is obtained using the extrusion process. Empirical equations are normally used, which can be applied to extrusion with axial symmetry, or analytical ones are used such as Seibel's equation to evaluate the extrusion process based on the material flow tension. When we use the flow tension corresponding to the mean value of the velocity of extrusion deformation, the extrusion pressure is significantly underestimated, with relation to the experimentally measured pressure. This is because of the flow tension's heavy dependence on the velocity of deformation, which is typical of commercial zirconium alloys. Therefore, the pressure was estimated by calculating the power dissipated during the deformation assuming a velocity field of homogenous deformation in each stage of deformation but without considering friction forces between the work and the extrusion matrix. The flow tension for the torsion tests performed are compared with the results obtained by compression as reported in the literature. These results are compared with four extrusion sequences carried out with different: reduction rates, temperatures, and deformation velocities. The flow tension from the compression test presents greater tension values than those estimated by the torsion test. The origin of these differences is discussed and the conclusion is that they can be attributed to the different crystallography textures generated in both tests. Once the correction is made for the texture variation, the flow tension values evaluated with both testing types in samples of Zircaloy-4 are the same. The peculiarities of each test in relation to the extrusion process are discussed. Despite the very simplified hypotheses that were assumed, the extrusion pressures calculated with the compression and torsion flow tension results, considering their dependence on the speed of deformation and temperature variation during

  20. Simulation of sheet metal extrusion processes with Arbitrary Lagrangian-Eulerian method

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Xin-cun; ZHAO Zhen; XIANG Hua; LI Cong-xin

    2008-01-01

    An Arbitrary Lagrangian-Eulerian(ALE) method was employed to simulate the sheet metal extrusion process, aiming at avoiding mesh distortion and improving the computational accuracy. The method was implemented based on MSC/MARC by using a fractional step method, i.e. a Lagrangian step followed by an Euler step. The Lagrangian step was a pure updated Lagrangian calculation and the Euler step was performed using mesh smoothing and remapping scheme. Due to the extreme distortion of deformation domain, it was almost impossible to complete the whole simulation with only one mesh topology. Therefore, global remeshing combined with the ALE method was used in the simulation work. Based on the numerical model of the process, some deformation features of the sheet metal extrusion process, such as distribution of localized equivalent plastic strain, and shrinkage cavity, were revealed. Furthermore, the differences between conventional extrusion and sheet metal extrusion process were also analyzed.

  1. A general extrudate bulk density model for both twin-screw and single-screw extruder extrusion cooking processes

    OpenAIRE

    Cheng, Hongyuan; Friis, Alan; Høeg Hansen, Jonas; Tolderlund Rasmussen, Hanne

    2010-01-01

    Effects of extrusion parameters and raw materials on extrudate expansion are respectively investigated in a twin-screw extruder and a single-screw extruder extrusion cooking experiments for fish feed, wheat, and oat & wheat mixture processing. A new phenomenological model is proposed to correlated extrudate bulk density, extrusion parameters and raw material changes based on the experimental results. The average absolute deviation (AAD) of the correlation is 2.2% for fish feed extrusion in th...

  2. MODELING EXTRUSION PROCESSING OF AQUACULTURE FEED INCORPORATING DISTILLERS GRAINS

    Science.gov (United States)

    Three ingredient blends containing 20, 30, and 40% Distillers Dried Grains with Solubles (DDGS), with a net protein adjusted to 28% were prepared. Extrusion studies were conducted at 3 levels of moisture content, 3 levels of barrel temperature profile, and 5 levels of screw speed in a single screw e...

  3. Unique microstructure and property of a 2024 aluminum alloy subjected to upsetting extrusion multiple processing

    Institute of Scientific and Technical Information of China (English)

    LI Xiaoqiang; LI Yuanyuan; CHEN Weiping; LONG Yan; HU Lianxi; WANG Erde

    2004-01-01

    The microstructure and hardness of a 2024 aluminum alloy subjected to multi-pass upsetting extrusion at ambient temperature were studied. Experimental results indicated that with the number of upsetting extrusion passes increasing, the grains of the alloy are gradually refined and the hardness increases correspondingly. After ten passes of upsetting extrusion processing, the grain size decreases to less than 200 nm in diameter and the sample maintains its original shape, while the hardness is double owing to equal-axial ultrafine grains and work hardening effect caused by large plastic deformation.

  4. Effect of hot extrusion process on microstructure and mechanical properties of hypereutectic Al-Si alloys

    OpenAIRE

    Li Runxia; Yu Fuxiao; Zuo Liang

    2011-01-01

    The hypereutectic Al-Si alloy was fabricated by hot extrusion process after solidified under electromagnetic stirring, and the microstructure and mechanical properties of the alloy were studied. The results show that the ultimate tensile strength and elongation of the alloy reached 229.5 MPa and 4.6%, respectively with the extrusion ratio of 10, and 263.2 MPa and 5.4%, respectively with extrusion ratio of 20. This indicates that the mechanical properties of the alloy are obviously improved w...

  5. Effect of hot extrusion process on microstructure and mechanical properties of hypereutectic Al-Si alloys

    Directory of Open Access Journals (Sweden)

    Li Runxia

    2011-02-01

    Full Text Available The hypereutectic Al-Si alloy was fabricated by hot extrusion process after solidified under electromagnetic stirring, and the microstructure and mechanical properties of the alloy were studied. The results show that the ultimate tensile strength and elongation of the alloy reached 229.5 MPa and 4.6%, respectively with the extrusion ratio of 10, and 263.2 MPa and 5.4%, respectively with extrusion ratio of 20. This indicates that the mechanical properties of the alloy are obviously improved with the increase of extrusion ratio. After hot extruded, the primary Si, eutectic Si, Mg2Si, AlNi, Al7Cu4Ni and Al-Si-Mn-Fe-Cr-Mo phases are refined to different extent, and the efficiency of refinement is obvious more and more with the increase of extrusion ratio. After T6 heat treatment, the sharp corners of these phases become passivated and roundish, and the mechanical properties are improved. The ultimate tensile strength of the extruded alloy after T6 heat treatment reaches 335.3 MPa with extrusion ratio of 10 and 353.6 MPa with extrusion ratio of 20.

  6. Structure optimization of porthole die based on aluminum profile extrusion process numerical simulation

    Institute of Scientific and Technical Information of China (English)

    WU Xiang-hong; ZHAO Guo-qun; LUAN Yi-guo; LOU Shu-mei; MA Xin-wu

    2006-01-01

    Porthole die extrusion method is used to produce hollow aluminum profile. Due to the complexity of the porthole die structure and the material flow, it is very difficult to get ideal profile products with the firstly designed die structure. Finite volume numerical simulation was used to analyze the extrusion process of a hollow profile with porthole die and the problem of non-uniform material flow was found. Optimization was made to the originally designed die to solve the problem. Lower load, reasonable seaming location and even extruded forepart with uniform material flow in the optimized die extrusion were obtained. Guidelines to porthole die design were given and it is also concluded that finite volume method with Eulerian description avoids mesh regeneration and is suitable to numerical simulation of severe deformation processes, such as profile extrusion.

  7. Temperature Field for Improving Internal Quality of Stretched Round Billet

    Institute of Scientific and Technical Information of China (English)

    QIU Ping; XIAO Hong

    2009-01-01

    Based on the rigid-plastic theory, using a coupled thermomechanieal model, the stretching process of a cir-cular section billet is simulated by means of FEM software Deform-2D. Through the distribution of internal stress fields of stretched round billet, it is found that the shear stress field is the main factor to induce Mannesmann's effect. The simulation results show that a reasonable distribution of the temperature field may improve the internal quality of the circular section billet in the stretching process.

  8. Lubrication in Hot Tube Extrusion of Superalloys and Ti Alloys

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Tubular products made of superalloys and titanium alloys usually work in high temperature environment and applied heavy loading. Hot extrusion is the best technology to form tubular billets with fine microstructures and good mechanical properties. Lubrication is one of the key techniques in hot extrusion, glass lubricants are most suitable for hot extrusion. Lubrication technique in hot extrusion is dealt with in this paper, the lubrication principle of hot tube extrusion is presented. Experiments of glass lubricated backward tube extrusion of titanium alloys and forward tube extrusion of superalloys are also discussed.

  9. Properties of seam welds produced with different extrusion parameters

    OpenAIRE

    A. Bozacl; M.S. Keskin; S. Bingol

    2007-01-01

    Purpose: This study focuses to investigate the effects of different extrusion parameters on microstructural properties of seam (longitudinal) welds in aluminum extrusion profiles.Design/methodology/approach: To realize the study, it is studied on a hollow extrusion profile type which has seam weld zones. The experimental profile was produced in different temperatures, billet temperatures and ram speeds by a real extrusion press which has a capacity of 1460 tones. These parameters are some of ...

  10. Extrusion Process by Finite Volume Method Using OpenFoam Software

    International Nuclear Information System (INIS)

    The computational codes are very important tools to solve engineering problems. In the analysis of metal forming process, such as extrusion, this is not different because the computational codes allow analyzing the process with reduced cost. Traditionally, the Finite Element Method is used to solve solid mechanic problems, however, the Finite Volume Method (FVM) have been gaining force in this field of applications. This paper presents the velocity field and friction coefficient variation results, obtained by numerical simulation using the OpenFoam Software and the FVM to solve an aluminum direct cold extrusion process.

  11. Forming of tubes and bars of alumina/LY12 composites by liquid extrusion process

    Institute of Scientific and Technical Information of China (English)

    齐乐华; 李贺军; 崔培玲; 史忠科

    2003-01-01

    Tube and bar products of aluminum alloy composites reinforced by alumina short-fiber were formed in a single process with liquid extrusion technology. The microstructure verifies that the reinforcing effect is obvious in the deformation direction since fibers are distributed along this direction, which is resulted from the flow and crystallization under pressure of liquid metal and large plastic deformation of solidified metal in the process. The interface between fiber and matrix belongs to mechanical bonding. The fractograph demonstrates ductile mode. Liquid extrusion process opens up a new way for fabricating tube, bar and shaped products.

  12. FEM Analysis of Force Parameters During Hot Extrusion Expanding and Reducing Tube Process

    Institute of Scientific and Technical Information of China (English)

    WANG Fenghui; JIAO Anyuan; LI Haidong; GAO Xingqi; YANG Siqiong

    2006-01-01

    In this paper, based on the plastic forming large deformation theory and thermodynamic elastic-plastic FEM, the process of expanding and reducing tube was analyzed by using nonlinear finite element software MARC. The coupled thermal-mechanical models for the thermal-extrusion tube process were established, and the dynamic simulation to them was carried out. By the study on 3D deformation regulation of the thermal-extrusion tube, the distribution of stress,strain and the curves between the force of extrusion and the distance were obtained. As a result, with only a small quantity of necessary experiments, the select of the schemes and parameters can conveniently be performed in the computers. So, not only large numbers of experiments can be avoided, but also trial-manufacture period is consumedly shortened and some costs may be saved. In addition, in order to validate our numerical calculation, an experiment of the tube made of 20 steel is presented in this paper. Good agreement is shown between measured and predicted results of the theoretical analysis model. The study provides a scientific basis for parametric optimizations of the thermal extrusion expanding and reducing tube production equipment. At the same time, the method used in the present paper has important referential value for studying the similar thermal extrusion parts.

  13. Die Radius Affecting Sheet Metal Extrusion Quality for Fine Blanking Process

    Directory of Open Access Journals (Sweden)

    Chatkaew Suriyapha

    2010-01-01

    Full Text Available Problem statement: Sheet metal extrusion is a process in which the punch penetrates one surface of the sheet metal material to cause it to extrude and flow toward the outlet of the die. Therefore, the process can invent different thickness of sheet metal work piece. From these advantages on the sheet metal extrusion, nowadays, it is generally used in many manufacturing of industrial elements fields. The Sheet Metal Extrusions in Fine Blanking (SME-FB advantages, over a conventional extrusion, are possible due to a blank holder force, a counterpunch force and a large die radius. However, the selection on those parameter values affects on the material flow and the surface quality on the extrusion parts also. Namely, it causes the crack surface and shrinkage failure which are the general problems in the SME-FB. Approach: Objective of this research was to study the effect of die radius on the SME-FB surface which investigated the formation of the failure defection with respect to the several die radiuses by using the Finite Element Method (FEM. Results: From the results, it indicated that applying the small die radius caused the material flow difficult resulting in the decreasing of smooth surface. Vice versa, in the case of large die radius, the material flow easy is resulting in the increasing of smooth surface. Conclusion: The FEM simulation results of a larger die radius will cause the residual stress at work piece.

  14. Examining the Effect of the Die Angle on Tool Load and Wear in the Extrusion Process

    Science.gov (United States)

    Nowotyńska, Irena; Kut, Stanisław

    2014-04-01

    The tool durability is a crucial factor in each manufacturing process, and this also includes the extrusion process. Striving to achieve the higher product quality should be accompanied by a long-term tool life and production cost reduction. This article presents the comparative research of load and wear of die at various angles of working cone during the concurrent extrusion. The numerical calculations of a tool load during the concurrent extrusion were performed using the MSC MARC software using the finite element method (FEM). Archard model was used to determine and compare die wear. This model was implemented in the software using the FEM. The examined tool deformations and stress distribution were determined based on the performed analyses. The die wear depth at various working cone angles was determined. Properly shaped die has an effect on the extruded material properties, but also controls loads, elastic deformation, and the tool life.

  15. AN ADAPTIVE EFG-FE COUPLING METHOD FOR THE NUMERICAL SIMULATION OF EXTRUSION PROCESSES

    Institute of Scientific and Technical Information of China (English)

    L.C.Liu; X.H.Dong; C.X.Li

    2008-01-01

    An adaptive EFG-FE coupling method is proposed and developed for the numerical simulation of lateral extrusion and forward-backward extrusion. Initially, the simulation has been implemented by using a conventional FE model. During the deforming process, mesh quality is checked at every incremental step. Distorted elements are automatically converted to EFG nodes, whereas, the less distorted elements are reserved. A new algorithm to generate EFG nodes and interface elements is presented. This method is capable of dealing with large deformation and has higher computational efficiency than using an EFG method wholly. Numerical results demonstrate that the adaptive EFG-FE coupling method has reasonable accuracy and is effective for local bulk metal forming such as extrusion processes.

  16. Using artificial neural networks to model extrusion processes for the manufacturing of polymeric micro-tubes

    Science.gov (United States)

    Mekras, N.; Artemakis, I.

    2012-09-01

    In this paper a methodology and an application example are presented aiming to show how Artificial Neural Networks (ANNs) can be used to model manufacturing processes when mathematical models are missing or are not applicable e.g. due to the micro- & nano-scaling, due to non-conventional processes, etc. Besides the ANNs methodology, the results of a Software System developed will be presented, which was used to create ANNs models for micro & nano manufacturing processes. More specifically results of a specific application example will be presented, concerning the modeling of extrusion processes for polymeric micro-tubes. ANNs models are capable for modeling manufacturing processes as far as adequate experimental and/or historical data of processes' inputs & outputs are available for their training. The POLYTUBES ANNs models have been trained and tested with experimental data records of process' inputs and outputs concerning a micro-extrusion process of polymeric micro-tubes for several materials such as: COC, PC, PET, PETG, PP and PVDF. The main ANN model of the extrusion application example has 3 inputs and 9 outputs. The inputs are: tube's inner & outer diameters, and the material density. The model outputs are 9 process parameters, which correspond to the specific inputs e.g. process temperature, die inner & outer diameters, extrusion pressure, draw speed etc. The training of the ANN model was completed, when the errors for the model's outputs, which expressed the difference between the training target values and the ANNs outputs, were minimized to acceptable levels. After the training, the micro-extrusion ANN is capable to simulate the process and can be used to calculate model's outputs, which are the process parameters for any new set of inputs. By this way a satisfactory functional approximation of the whole process is achieved. This research work has been supported by the EU FP7 NMP project POLYTUBES.

  17. Jute fiber reinforced polypropylene produced by continuous extrusion compounding. Part 1. Processing and ageing properties

    NARCIS (Netherlands)

    Oever, van den M.J.A.; Snijder, M.H.B.

    2008-01-01

    This article addresses the processing and ageing properties of jute fiber reinforced polypropylene (PP) composites. The composite has been manufactured by a continuous extrusion process and results in free flowing composite granules, comprising up to 50 weight percent (wt %) jute fiber in PP. These

  18. Microstructure analysis of aluminum extrusion: grain size distribution in AA6060, AA6082 and AA7075 alloys

    Energy Technology Data Exchange (ETDEWEB)

    Schikorra, M.; Tekkaya, A. E. [Institute of Forming Technology and Lightweight Construction, Dortmund (Germany); Donate, L.; Iomesani, L. [University of Bologna, Bologna (Italy)

    2007-10-15

    Microstructure and material flow of aluminum alloys have a significant influence on the mechanical properties and surface quality. In extrusion of aluminum billets at high temperatures the microstructure is dependent on the alloy and the forming and temperature history. A prediction of grain size and precipitation is of increasing importance in order to design the process by adjustment of parameters such as punch speed, temperatures, and quenching. To give references for microstructure prediction based on material flow, and with it strain and strain rate history, this paper deals with the microstructure during the extrusion process of AA6060, AA6082, and AA7075 alloys. Billets have been partly extruded to axisymmetric round profiles and the microstructure of the press rests consisting of the billet rests in container and die has been considered. Furthermore, these rests have been analyzed to show the material flow, dynamic and static recrystallization based on macro etchings and visible microstructure under different conditions, e.g. as in the area of high strain rate near the container wall, or in dead zones. To allow an accurate simulation of the extrusion process, punch force and temperature conditions during the tests have been measured and are presented in this paper, too.

  19. Preparation of semi-solid billet of magnesium alloy and its thixoforming

    Institute of Scientific and Technical Information of China (English)

    JIANG Ju-fu; LUO Shou-jing

    2007-01-01

    Preparation of semi-solid billet of magnesium alloy and thixoforming was investigated by applying equal channel angular extrusion to magnesium alloy. The results show that mechanical properties of AZ91D alloy at room temperature, such as yield strength(YS), ultimate tensile strength(UTS) and elongation, are enhanced greatly by four-pass equal channel angular extrusion(ECAE) at 573 K and microstructure of AZ91D alloy is refined to the average grain size of 20 μm. Through using ECAE as strain induced step in SIMA and completing melt activated step by semi-solid isothermal treatment, semi-solid billet with fine spheroidal grains of 25 μm can be prepared successfully. Compared with common SIMA, thixoformed satellite angle frame components using semi-solid billet prepared by new SIMA have higher mechanical properties at room temperature and high temperature of 373 K.

  20. PRELIMINARY INVESTIGATION OF PASTA EXTRUSION PROCESS: RHEOLOGICAL CHARACTERIZATION OF SEMOLINA DOUGH

    Directory of Open Access Journals (Sweden)

    Angelo Fabbri

    2007-06-01

    Full Text Available Rheological measurements were conducted on semolina doughs. Two doughs were considered, one directly taken from an extrusion plant and another mixed in lab conditions. A rotational viscometer was used in the plate-plate configuration. Creep tests were carried on too, to verify the possibility to neglect the elastic component of strain. It was investigated the influence of the temperature on the viscous behaviour of both doughs, while only on the lab mixed dough was tested the influence of moisture content. The aim of this research is the determination of a rheological model useful for a subsequent CFD analysis of the extrusion process.

  1. Modelling extrudate expansion in a twin-screw food extrusion cooking process through dimensional analysis methodology

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2010-01-01

    A new phenomenological model is proposed to correlate extrudate expansion and extruder operation parameters in a twin-screw food extrusion cooking process. Buckingham's pi dimensional analysis method is applied to establish the model. Three dimensionless groups, i.e. pump efficiency, water content...... extrusion, respectively. An alternative four-coefficient extrudate expansion equation is also suggested for the three dimensionless groups. The average deviations of the alternative equation are respectively 5.8% and 2.5% in correlation with the same set of experimental data....

  2. Food extrusion.

    Science.gov (United States)

    Harper, J M

    1978-01-01

    Extrusion processing has become an important food process in the manufacture of pasta, ready-to-eat cereals, snacks, pet foods, and textured vegetable protein (TVP). An extruder consists of tightly fitting screw rotating within a stationary barrel. Preground and conditioned ingredients enter the screw where they are conveyed, mixed, and heated by a variety of processes. The product exits the extruder through a die where it usually puffs and changes texture from the release of steam and normal forces. Mathematical models for extruder flow and torque have been found useful in describing exclusion operations. Scale-up can be facilitated by the application of these models. A variety of food extruder designs have developed. The differences and similarity of design are discussed. Pertinent literature on the extrusion of cereal/snack products, full-fat soy, TVP, pet foods (dry and semi-moist), pasta, and beverage or other food bases are discussed. In many of these applications, the extruder is a high temperature, short time process which minimizes losses in vitamins and amino acids. Color, flavor, and product shape and texture are also affected by the extrusion process. Extrusion has been widely applied in the production of nutritious foods. Emphasis is placed on the use of extrusion to denature antinutritional factors and the improvement of protein quality and digestibility.

  3. Food extrusion.

    Science.gov (United States)

    Harper, J M

    1978-01-01

    Extrusion processing has become an important food process in the manufacture of pasta, ready-to-eat cereals, snacks, pet foods, and textured vegetable protein (TVP). An extruder consists of tightly fitting screw rotating within a stationary barrel. Preground and conditioned ingredients enter the screw where they are conveyed, mixed, and heated by a variety of processes. The product exits the extruder through a die where it usually puffs and changes texture from the release of steam and normal forces. Mathematical models for extruder flow and torque have been found useful in describing exclusion operations. Scale-up can be facilitated by the application of these models. A variety of food extruder designs have developed. The differences and similarity of design are discussed. Pertinent literature on the extrusion of cereal/snack products, full-fat soy, TVP, pet foods (dry and semi-moist), pasta, and beverage or other food bases are discussed. In many of these applications, the extruder is a high temperature, short time process which minimizes losses in vitamins and amino acids. Color, flavor, and product shape and texture are also affected by the extrusion process. Extrusion has been widely applied in the production of nutritious foods. Emphasis is placed on the use of extrusion to denature antinutritional factors and the improvement of protein quality and digestibility. PMID:378548

  4. Effect of extrusion processing on immune activation properties of hazelnut protein in a mouse model.

    Science.gov (United States)

    Ortiz, Tina; Para, Radhakrishna; Gonipeta, Babu; Reitmeyer, Mike; He, Yingli; Srkalovic, Ines; Ng, Perry K W; Gangur, Venu

    2016-09-01

    Although food processing can alter food allergenicity, the impact of extrusion processing on in vivo hazelnut allergenicity is unknown. Here, we tested the hypothesis that extrusion processing will alter the immune activation properties of hazelnut protein (HNP) in mice. Soluble extrusion-processed HNP (EHNP) was prepared and evaluated for immune response using an established transdermal sensitization mouse model. Mice were sensitized with identical amounts of EHNP versus raw HNP. After confirming systemic IgE, IgG1 and IgG2a antibody responses, oral hypersensitivity reaction was quantified by hypothermia shock response (HSR). Mechanism was studied by measuring mucosal mast cell (MMC) degranulation. Compared to raw HNP, the EHNP elicited slower but similar IgE antibody (Ab) response, lower IgG1 but higher IgG2a Ab response. The EHNP exhibited significantly lower oral HSR as well as MMC degranulation capacity. These results demonstrate that the extrusion technology can be used to produce soluble HNP with altered immune activation properties. PMID:27251648

  5. Comparison of Mesh Adaptivity Schemes in Finite ElementSimulation of Tube Extrusion Process

    Directory of Open Access Journals (Sweden)

    K. K. Pathak

    2008-05-01

    Full Text Available In this study, finite element simulation of tube extrusion process has been carried outconsidering different mesh adaptivity schemes. A comparison of these schemes has been madebased on stress, strain distribution, and load-stroke curves. Based on the finite element results,it is observed that the success of the computer simulation is dependent on the mesh refinementcriteria.

  6. Analysis of Crystallographic Textures in Aluminum Plates Processed by Equal Channel Angular Extrusion

    DEFF Research Database (Denmark)

    Li, Saiyi; Mishin, Oleg

    2014-01-01

    A modeling and experimental investigation has been conducted to explore the effect of processing route on texture evolution during equal channel angular extrusion (ECAE) of aluminum plate samples. It is found that although the textures in the plates develop along orientation fibers previously...

  7. Modelo matemático aplicado ao processo de extrusão de argilas Mathematical model applied to the process of clay extrusion

    Directory of Open Access Journals (Sweden)

    F. A. Andrade

    2011-06-01

    Full Text Available As argilas, quando misturadas com água, adquirem a propriedade chamada plasticidade que tem papel fundamental durante o seu processamento. As técnicas empregadas na caracterização da plasticidade muitas vezes não revelam resultados quantitativos que permitam sua aplicação em modelos matemáticos do processo de conformação das argilas. Este trabalho teve por objetivo desenvolver um modelo matemático para cálculo da pressão média de extrusão, avaliando a plasticidade através de ensaios de compressão. Em seguida, os resultados teóricos da pressão de extrusão foram comparados aos resultados experimentais, sendo encontrado um bom acordo entre eles. Foi possível observar uma correlação entre tensão efetiva de compressão e pressão de extrusão. Para a equação que modela o processo de extrusão, a tensão efetiva obtida pelo ensaio de compressão foi um parâmetro significativo que revela o comportamento da argila durante o seu processamento.The clays when mixed with water acquire the property known as plasticity, which plays a key role during processing. The techniques used to characterize the plasticity often do not show quantitative results that allow its application in mathematical models of the forming process of clays. This study aimed to develop a mathematical model for calculating the average pressure of extrusion, evaluating the plasticity through compression tests. Then, the theoretical results of the extrusion pressure were compared to experimental results and a good agreement was found between them. It was possible to observe a correlation between effective stress of compression and extrusion pressure. For the extrusion process modeling equation, the effective stress obtained by compression test was a significant parameter that reveals the behavior of the clay during processing.

  8. FORMING TUBES AND RODS OF URANIUM METAL BY EXTRUSION

    Science.gov (United States)

    Creutz, E.C.

    1959-01-27

    A method and apparatus are presented for the extrusion of uranium metal. Since uranium is very brittle if worked in the beta phase, it is desirable to extrude it in the gamma phase. However, in the gamma temperature range thc uranium will alloy with the metal of the extrusion dic, and is readily oxidized to a great degree. According to this patent, uranium extrusion in thc ganmma phase may be safely carried out by preheating a billet of uranium in an inert atmosphere to a trmperature between 780 C and 1100 C. The heated billet is then placed in an extrusion apparatus having dies which have been maintained at an elevated temperature for a sufficient length of time to produce an oxide film, and placing a copper disc between the uranium billet and the die.

  9. Friction phenomena in hydrostatic extrusion of magnesium

    NARCIS (Netherlands)

    Moodij, Ellen

    2014-01-01

    When magnesium is hydrostatically extruded an inconsistent and sometimes bad surface quality is encountered. In hydrostatic extrusion the billet is surrounded by a lubricant, usually castor oil. The required pressure to deform the material is applied onto this lubricant and not directly to the bill

  10. DEPOSITION OF TiBN HARD FILMS ON HOT-WORKING-STEEL DIES FOR ALUMINIUM EXTRUSION VIA A DUPLEX PROCESS

    Institute of Scientific and Technical Information of China (English)

    K. MUller

    2001-01-01

    Hot working steels have been used as die materials for hot extrusion of aluminium.Due to tribological interaction at elevated temperature between the die bearing and thesurface of extruded aluminium profiles, not only the surface quality of the extrudedproduct, but also the lifetime of the dies decreases. Deposition of TiBN hard films onthe die bearing could improve the die performance. Treatment should be done in aduplex process process combining a plasma nitriding pretreatment (PN) and a plasmaassisted chemical vapour deposition (PACVD) of TiBN. In this study the influence ofthe process conditions on the properties of the duplex coatings was investigated. Therelationship between structure and mechanical property was researched. For testingthese TiBN hardfilms under elevated temperature conditions and for comparison withother possible coatings special extrusion dies with different coated bearings were used.The extrusion trials were performed on the 8MN-extrusion press at the research anddevelopment center for extrusion, Technical University of Berlin.

  11. Study on Hot Deformation Behavior of 7085 Aluminum Alloy during Backward Extrusion Process

    Directory of Open Access Journals (Sweden)

    R. B. Mei

    2015-01-01

    Full Text Available Compression test was carried out and the true stress-strain curves were obtained from the hot compression of 7085 alloy. A numerical simulation on the deformation behavior of 7085 aluminum alloy during the backward extrusion was also performed by finite element method. The results show that dynamic recrystallization occurs in the hot compression of 7085 alloy and the peak stress reaches higher values as the strain rate increases and deformation temperature decreases. The backward extrusion processes include contact deformation, initial deformation, and steady deformation. Severe plastic deformation of shear and compression occurs when the metal flowed into the channel between fillet of punch and wall of die so that the grain size can be refined by backward extrusion. The deformation in the region of top of wall is too small to meet the mechanical properties of requirements and the metal usually needs to be trimmed. The experiments with the same parameters as simulation had been carried out and the experimental cup after extrusion has better quality.

  12. 厚壁无缝钢管垂直挤压模具及润滑工艺研究%Study on the vertical extrusion process of thick seamless steel pipe

    Institute of Scientific and Technical Information of China (English)

    边翊; 杨秀清; 马晓晖; 钟志平; 王守华

    2011-01-01

    针对厚壁无缝钢管的特点,对热挤压法制造无缝钢管中的垂直挤压工艺进行研究.介绍了厚壁无缝钢管热挤压的工艺流程,并重点分析模具结构和润滑条件热挤压工艺过程中的两大重要因素.最终提出了多角度挤压入模角的模具结构及模具一坯料复合润滑方案,在降低挤压力的同时获得了表面质量较高、综合力学性能较好的厚壁无缝钢管.%Abstract:According to the characteristics of thick-walled seamless steel pipe, the vertical extrusion process of the thick-walled seamless steel pipe is researched in this work. The whole process chain is introduced and the two key factors including die structure and lubrication condition are discussed in detail. In the end, the die structure with multi-angular die angle and a reasonable die-billet composite lubrication program are put forward and the thick-walled seamless steel pipe with good surface quality and combined mechanical properties is obtained under lower extrusion force.

  13. New challenges in polymer foaming: A review of extrusion processes assisted by supercritical carbon dioxide

    OpenAIRE

    Sauceau, Martial; Fages, Jacques; Common, Audrey; Nikitine, Clémence; Rodier, Elisabeth

    2011-01-01

    International audience It is well known that supercritical carbon dioxide (sc-CO 2) is soluble in molten polymers and acts as a plasticizer. The dissolution of sc-CO 2 leads to a decrease in the viscosity of the liquid polymer, the melting point and the glass transition temperature. These properties have been used in several particle generation processes such as PGSS (particles from gas saturated solutions). It is therefore highly likely that extrusion processes would benefit from the use ...

  14. Extrusion process by finite volume method using OpenFoam software

    OpenAIRE

    Martins, Marcelo Matos; Bressan, Jose Divo; Button, Sergio Tonini; Ivankovic, Alojz

    2011-01-01

    The computational codes are very important tools to solve engineering problems. In the analysis of metal forming process, such as extrusion, this is not different because the computational codes allow analyzing the process with reduced cost. Traditionally, the Finite Element Method is used to solve solid mechanic problems, however, the Finite Volume Method (FVM) have been gaining force in this field of applications. This paper presents the velocity field and friction coefficient variation res...

  15. A process planning system with feature based neural network search strategy for aluminum extrusion die manufacturing

    CERN Document Server

    Butdee, S; Tichkiewitch, Serge

    2009-01-01

    Aluminum extrusion die manufacturing is a critical task for productive improvement and increasing potential of competition in aluminum extrusion industry. It causes to meet the efficiency not only consistent quality but also time and production cost reduction. Die manufacturing consists first of die design and process planning in order to make a die for extruding the customer's requirement products. The efficiency of die design and process planning are based on the knowledge and experience of die design and die manufacturer experts. This knowledge has been formulated into a computer system called the knowledge-based system. It can be reused to support a new die design and process planning. Such knowledge can be extracted directly from die geometry which is composed of die features. These features are stored in die feature library to be prepared for producing a new die manufacturing. Die geometry is defined according to the characteristics of the profile so we can reuse die features from the previous similar p...

  16. Solidification Structure and Macrosegregation of Billet Continuous Casting Process with Dual Electromagnetic Stirrings in Mold and Final Stage of Solidification: A Numerical Study

    Science.gov (United States)

    Jiang, D.; Zhu, M.

    2016-08-01

    Coupling macroscale heat transfer and fluid flow with microscale grain nucleation and crystal growth, a mixed columnar-equiaxed solidification model was established to study the SWRT82B steel solidification structure and macrosegregation in 160 mm × 160 mm billet continuous casting with dual electromagnetic stirrings in mold and final stage of solidification (M-EMS and F-EMS). In the model, the phases of liquid, columnar, and equiaxed were treated separately and the initial growing equiaxed phase, which could move freely with liquid, was regarded as slurry. To obtain the equiaxed grains nucleation and columnar front evolution, the unit tracking method and the columnar front tracking model were built. The model was validated by magnetic induction intensity of stirrer, billet surface temperature, and carbon segregation. The equiaxed phase evolution and the solute transport with effect of fluid flow and grains transport were described in this article. The results show that the equiaxed phase ratio will not increase obviously with higher current intensity of M-EMS, while the negative segregation near the strand surface becomes more serious. The negative segregation zone near the billet center and the center positive segregation come into being with the effect of equiaxed grains sedimentation and liquid thermosolutal flow. It is also found that the liquid solute transport in the F-EMS zone becomes the main factor with higher current intensity rather than the solidification rate, and therefore, the final billet center segregation decreases first and then turns to rise with the current intensity. The optimal current intensities of M-EMS and F-EMS proposed for SWRT82B billet continuous casting are 200 and 400 A, respectively.

  17. A Technique to Determine Billet Core Charge Weight for P/M Fuel Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Peacock, H.B.

    2001-07-02

    The core length in an extruded tube depends on the weight of powder in the billet core. In the past, the amount of aluminum powder needed to give a specified core length was determined empirically. This report gives a technique for calculating the weight of aluminum powder for the P/M core. An equation has been derived which can be used to determine the amount of aluminum needed for P/M billet core charge weights. Good agreement was obtained when compared to Mark 22 tube extrusion data. From the calculated charge weight, the elastomeric bag can be designed and made to compact the U3O8-Al core.

  18. A Technique to Determine Billet Core Charge Weight for P/M Fuel Tubes

    International Nuclear Information System (INIS)

    The core length in an extruded tube depends on the weight of powder in the billet core. In the past, the amount of aluminum powder needed to give a specified core length was determined empirically. This report gives a technique for calculating the weight of aluminum powder for the P/M core. An equation has been derived which can be used to determine the amount of aluminum needed for P/M billet core charge weights. Good agreement was obtained when compared to Mark 22 tube extrusion data. From the calculated charge weight, the elastomeric bag can be designed and made to compact the U3O8-Al core

  19. A Novel Continuous Extrusion Process to Fabricate Wedge-Shaped Light Guide Plates

    Directory of Open Access Journals (Sweden)

    Wen-Tse Hsiao

    2013-01-01

    Full Text Available Backlight modules are key components in thin-film transistor liquid crystal displays (TFT-LCD. Among the components of a backlight module, the light guide plate (LGP plays the most important role controlling the light projected to the eyes of users. A wedge-shaped LGP, with its asymmetrical structure, is usually fabricated by an injection proces, but the fabrication time of this process is long. This study proposes a continuous extrusion process to fabricate wedge-shaped LGPs. This continuous process has advantages for mass production. Besides a T-die and rollers, this system also has an in situ monitor of the melt-bank that forms during the extrusion process, helping control the plate thickness. Results show that the melt bank has a close relationship with the plate thickness. The temperature of the bottom heater and roller was adjusted to reduce the surface deformation of the wedge-shaped plate. This continuous extrusion system can successfully manufacture wedge-shaped LGPs for mass production.

  20. A method for manufacturing a tool part for an injection molding process, a hot embossing process, a nano-imprint process, or an extrusion process

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a method for manufacturing a tool part for an injection molding process, a hot embossing process, nano-imprint process or an extrusion process. First, there is provided a master structure (10) with a surface area comprising nanometre-sized protrusions (11) with a...

  1. Reduction of cyanogenic glycosides by extrusion - influence of temperature and moisture content of the processed material

    Directory of Open Access Journals (Sweden)

    Čolović Dušica S.

    2015-01-01

    Full Text Available Тhe paper presents results of the investigation of the influence of extrusion temperature and moisture content of treated material on the reduction of cyanogenic glycosides (CGs in linseed-based co-extrudate. CGs are the major limitation of the effective usage of linseed in animal nutrition. Hence, some technological process must be applied for detoxification of linseed before its application as a nutrient. Extrusion process has demonstrated several advantages in reducing the present CGs, since it combines the influences of heating, shearing, high pressure, mixing, etc. According to obtained results, the increase in both temperature and moisture content of the starting mixture decreased the content of CGs in the processed material. HCN content, as a measurement of GCs presence, ranged from 25.42 mg/kg, recorded at the moisture content of 11.5%, to 126 mg/kg, detected at the lowest moisture content of 7%. It seems that moisture content and temperature had the impact on HCN content of equal importance. However, the influence of extrusion parameters other than temperature and moisture content could not be neglected. Therefore, the impact of individual factors has to be tested together. [Projekat Ministarstva nauke Republike Srbije, br. III 46012

  2. Study on the combustion behavior of high impact polystyrene nanocomposites produced by different extrusion processes

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available The combustion behavior of a blend made of high impact polystyrene (HIPS with sodium montmorillonite (MMT-Na+ and triphenyl phosphite (TPP, as a halogen-free flame retardant, is analyzed in detail in this work. The blend is processed through various extrusion methods aimed to improve clay dispersion. The UL94 method in vertical position, oxygen index and cone calorimetric measurements assess HIPS blend behavior in combustion. TGA, FTIR, SEM and X-ray measurements, together with mechanical and rheological tests evaluate the thermal degradation, morphology, intercalation and degree of dispersion of particles. The use of a static-mixing die placed at the extreme of a single screw extruder improves clay platelets distribution and reduces the peak heat release rate better than employing a twin screw extrusion process. In addition, mechanical and rheological properties are affected substantially by changing the extrusion process. A correlation between clay dispersion and HIPS fire retardant properties is found, as the peak heat release rate decreases with good clay dispersion in cone calorimetric tests.

  3. ENERGY EFFICIENCY IN CUTTING PROCESS OF COMPONENT BILLET SURFACE ON ANALYSIS BASIS FOR ENERGY-CONSUMPTION INDICES OF TECHNOLOGICAL EQUIPMENT

    Directory of Open Access Journals (Sweden)

    V. Adamenko

    2012-01-01

    Full Text Available The paper contains investigation results and proposes a method for calculation of optimum cutting rate. The method takes into account energy-consumption indices of technological equipment that permits to improve technological energy efficiency of cutting process.

  4. Cold hydrostatic extrusion of powder metallurgy processed superconducting materials

    International Nuclear Information System (INIS)

    Hydrostatically extruded multifilamentary composites of Cu-Nb, Cu-Nb with a central tin core and Nb-Al were directly drawn to fine wires without intermediate annealing. Uniform deformation was observed throughout the process. Cu-Nb composite wires were Sn plated for external diffusion. Overall critical current densities of better than 104 A/cm2 at 16 T were achieved for Nb3Sn-Cu composite wires with nominal areal reductions of 2000

  5. Resistance of Bacillus amyloliquefaciens spores to melt extrusion process conditions

    OpenAIRE

    Ciera, Lucy Wanjiru; Beladjal, Lynda; Almeras, Xavier; Gheysens, Tom; Nierstrasz, Vincent; Van Langenhove, Lieva; Mertens, Johan

    2014-01-01

    With the increasing demand for functionalised textile materials, industry is focusing on research that will add novel properties to textiles. Bioactive compounds and their benefits have been and are still considered as a possible source of unique functionalities to be explored. However, incorporating bioactive compounds into textiles and their resistance to textile process parameters has not yet been studied. In this study, we developed a system to study the resistance of Bacillus amyloliquef...

  6. Antioxidants and its Properties as Affected by Extrusion Process: A Review.

    Science.gov (United States)

    Wani, Sajad A; Kumar, Pradyuman

    2015-01-01

    Antioxidants are important for plant and animal's life or health. These are the substances that protect them from the damage produced by unstable molecules called as free radicals. There are various types of antioxidants to be reported both natural as well as synthetic such as melatonin, Vitamin C, glutathione, tocopherols and tocotrienols, BHA and BHT, etc. A new antioxidant 5-O-[6˝-(3- hydroxy-3methyl glutarate) β-D-glucodise was found while studying bioactive antioxidants from plant foods for nutraceutical product development. Antioxidants have been used for increasing shelf life of various food products including extruded product. Antioxidants, their beneficial advantages and the effect of extrusion on antioxidants were reviewed and found to be effective in increasing the shelf life. This review article discusses recent patents, presents importance of antioxidant, phytochemicals and effect of process of extrusion on antioxidants. PMID:26152136

  7. Dynamic Water Modeling and Application of Billet Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    LIU Wen-hong; XIE Zhi; JI Zhen-ping; WANG Biao; LAI Zhao-yi; JIA Guang-lin

    2008-01-01

    The continuous casting process is used for solidifying molten steel into semi-finished steel. The technology of secondary cooling is extremely important for output of the casting machine and billet quality. A dynamic water model was introduced, including solidification model in the secondary cooling, feedforward control strategy based on continuous temperature measurement in tundish, and feedback control strategy based on surface temperature measurement. The mathematical model of solidification process was developed according to the principle of solidification, and the solidification model was validated by measuring billet shell thickness through shooting nail and sulfur print. Primary water distribution was calculated by the solidification model according to procedure parameters, and it was adjusted by the other two control strategies online. The model was applied on some caster and billet quality was obviously improved, indicating that the dynamic water model is better than conventional ones.

  8. Solder extrusion pressure bonding process and bonded products produced thereby

    Science.gov (United States)

    Beavis, Leonard C.; Karnowsky, Maurice M.; Yost, Frederick G.

    1992-01-01

    Production of soldered joints which are highly reliable and capable of surviving 10,000 thermal cycles between about -40.degree. C. and 110.degree. C. Process involves interposing a thin layer of a metal solder composition between the metal surfaces of members to be bonded and applying heat and up to about 1000 psi compression pressure to the superposed members, in the presence of a reducing atmosphere, to extrude the major amount of the solder composition, contaminants including fluxing gases and air, from between the members being bonded, to form a very thin, strong intermetallic bonding layer having a thermal expansion tolerant with that of the bonded members.

  9. RESOURCE-SAVING TECHNOLOGY FOR HIGH-SPEED HOT EXTRUSION OF BIMETALLIC ROD PARTS

    Directory of Open Access Journals (Sweden)

    I. V. Kachanov

    2016-01-01

    Full Text Available Processes of high-speed shaping changes and especially high-speed hot extrusion create efficient conditions for treatment of weakly plastic and poorly deformable materials which are widely used in tool making facilities. Due to the fact that high-speed stamping provides accurate billets with increased mechanical properties, it can be used as a technological process for manufacturing rod parts of die tooling operating under conditions of increased loads and wear. The purpose of the given paper is to carry out experimental investigations on the possibility to obtain a bimetallic rod tool where structural steel is considered as a basis of the tool and a working cavity is made of high-alloyed tool steel with its saving up to 90 %. A scheme of loading and geometry of conjugated surfaces of the composite billet have been developed in the paper. Technology for obtaining bimetallic rod parts of die tooling with deformation at speed of vд = 70–80 m/s and composite billet temperature of Т = (1150±20 ºС has been experimentally tested with formation of a compound due to plastic flow of two billet parts on contact surface with removal of surface oxide films. Microstructures of the bimetallic compounds obtained with the help of high-speed hot extrusion method for compositions of structural and high-alloy steels have been investigated and their high quality has been proved during the investigations. Dependences of micro-hardness distribution have been established outbound two steel contact plane in the zone of connection that are characterized by a minimum micro-hardness value in the connection joint. Availability of more plastic zone in the contact plane contributes to reduction of residual stresses due to their relaxation in this zone and higher joint strength.

  10. Dynamic recrystallization and texture evolution of Mg–Y–Zn alloy during hot extrusion process

    International Nuclear Information System (INIS)

    The microstructure and texture evolution of Mg98.5Y1Zn0.5 and Mg92.5Y5Zn2.5 (atomic percent) alloys during hot extrusion were systematically investigated. The coarse LPSO phases with higher volume fraction (∼ 57%) suppressed the twinning generation in the initial stage of extrusion, and accelerated the dynamic recrystallization through the particle deformation zones. Therefore, the volume fraction of DRXed grains in as-extruded Mg92.5Y5Zn2.5 alloy was much higher than that of Mg98.5Y1Zn0.5 alloy. The intensive recrystallization process resulted in the conventional basal texture weakening, although the texture evolution was mainly dominated by flow behavior. The dynamic recrystallization behavior in Mg92.5Y5Zn2.5 alloy restricted the formation of deformation texture, and thus the more random texture was observed during the whole extrusion process. - Highlights: • The densely coarse LPSO phases suppressed the twinning deformation. • Coarse LPSO phases induced the particle stimulated nucleation effect. • Dynamic recrystallization resulted in the basal texture weakening effect

  11. Dynamic recrystallization and texture evolution of Mg–Y–Zn alloy during hot extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Tong, L.B. [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Li, X. [Institut für Metallkunde und Metallphysik, RWTH-Aachen University, D-52056 Aachen (Germany); Guangzhou Research Institute of Non-ferrous Metals, Guangzhou 510651 (China); Zhang, D.P.; Cheng, L.R.; Meng, J. [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zhang, H.J., E-mail: hongjie@ciac.ac.cn [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2014-06-01

    The microstructure and texture evolution of Mg{sub 98.5}Y{sub 1}Zn{sub 0.5} and Mg{sub 92.5}Y{sub 5}Zn{sub 2.5} (atomic percent) alloys during hot extrusion were systematically investigated. The coarse LPSO phases with higher volume fraction (∼ 57%) suppressed the twinning generation in the initial stage of extrusion, and accelerated the dynamic recrystallization through the particle deformation zones. Therefore, the volume fraction of DRXed grains in as-extruded Mg{sub 92.5}Y{sub 5}Zn{sub 2.5} alloy was much higher than that of Mg{sub 98.5}Y{sub 1}Zn{sub 0.5} alloy. The intensive recrystallization process resulted in the conventional basal texture weakening, although the texture evolution was mainly dominated by flow behavior. The dynamic recrystallization behavior in Mg{sub 92.5}Y{sub 5}Zn{sub 2.5} alloy restricted the formation of deformation texture, and thus the more random texture was observed during the whole extrusion process. - Highlights: • The densely coarse LPSO phases suppressed the twinning deformation. • Coarse LPSO phases induced the particle stimulated nucleation effect. • Dynamic recrystallization resulted in the basal texture weakening effect.

  12. The effect of extrusion processing on the physiochemical properties of extruded orange pomace.

    Science.gov (United States)

    Huang, Ya-Ling; Ma, Ya-Sheng

    2016-02-01

    Soluble dietary fibre (SDF) is considered the most effective fraction of dietary fibre (DF) for human health. In this study, extrusion technology was applied to enhance the SDF obtained from orange pomace, a byproduct of juice extraction containing a high level of DF. The pomace was processed in a single-screw extruder at various barrel temperatures (X1; 115-135 °C), feed moistures (X2; 10-18 g/100g), and screw speeds (X3; 230-350 rpm). Based on response surface methodology, the optimum extrusion conditions, which produced a maximum SDF value of 30.36%, were as follows: barrel temperature, 129 °C; feed moisture, 15%; and screw speed, 299 rpm. Compared with unextruded pomace, SDF fraction in extrudate had a higher level of uronic acid. Furthermore, the extrusion process improved the physicochemical properties of extrudate, increasing the water-holding capacity, swelling, water solubility index, and cation-exchange capacity and decreasing the oil-holding capacity.

  13. Effect of extrusion processing parameters on microstructure and mechanical properties of as-extruded AZ31 sheets

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The AZ31 sheets were prepared by extrusion. The effects of the extrusion processing parameters including the temperature,extrusion ratio, and structure of the extrusion die on the microstructure and mechanical properties of the as-extruded AZ31 sheets were investigated. The results show that the partial grains grow abnormally.and the mechanical and anisotropic properties of the as-extruded AZ31 sheets have little change at the extrusion temperatures of 380-400 ℃ and the extrusion ratio of 13.3. With the increase of the extrusion ratio, the microstructure of the as-extruded AZ31 sheets by conventional die becomes finer and more uniform, and the elongation rate increases, but the strength decreases and its anisotropy becomes worse. Under the porthole die, finer and more uniform microstructure, higher mechanical properties and better anisotropy can be brought for the as-extruded AZ31 sheets.The extruded AZ31 sheets by the porthole die have better anneal process of 300℃ and 1 h.

  14. 3D FE Analysis of Thermal Behavior of Billet in Rod and Wire Hot Continuous Rolling Process

    Institute of Scientific and Technical Information of China (English)

    YUAN Si-yu; ZHANG Li-wen; LIAO Shu-lun; QI Min; ZHEN Yu; GUO Shu-qi

    2007-01-01

    An FE model was developed to study thermal behavior during the rod and wire hot continuous rolling process. The FE code MSC.Marc was used in the simulation using implicit static arithmetic. The whole rolling process of 30 passes was separated and simulated with several continuous 3D elastic-plastic FE models. A rigid pushing body and a data transfer technique were introduced into this model. The on-line experiments were conducted on 304 stainless steel and GCr15 steel hot continuous rolling process to prove the results of simulation by implicit static FEM. The results show that the temperature results of finite element simulations are in good agreement with experiments, which indicate that the FE model developed in this study is effective and efficient.

  15. Numerical Simulation on Process of Hydrostatic Extrusion for Tungsten Alloy through Concave Dies with Equal-strain Contour Lines

    Institute of Scientific and Technical Information of China (English)

    Zhaohui ZHANG; Fuchi WANG

    2001-01-01

    The numerical simulation to the process of hydrostatic extrusion for tungsten alloy through the concave dies with the equal-strain contour lines was carried out in this paper by the large deformation and elasto-plastic finite theory and ANSYS software. Both the pressure in the process of extrusion and the stress-strain distribution in the sample were analyzed, which founds a basis to the engineering application.

  16. Carbon Segregation of Bearing Steel Concasting Billet

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The formation mechanism of “white band” and central carbon segregation of high-carbon Cr bearing steel concasting billets are discussed in this paper. The maximum oxygen content in the steel produced by concasting process was 13x10-6 with an average oxygen content of 9.3x 10-6.Comparison of metallurgical quality and fatigue property between the concasting steel (CC) andingot casting steel (IC) showed that the carbon segregation (C/C0) in former steel was 0.92~1.10and its fatigue life was equal to that of the latter steel.

  17. EXPERIMENTS AND SIMULATIONS OF A NEW DEVELOPED FORMING TECHNOLOGY-SHEAR-EXTRUSION PROCESS OF COMPONENTS WITH BRANCHES

    Institute of Scientific and Technical Information of China (English)

    H.L. Yang; D.C. Kang; Z.L. Zhang; X.H. Piao; Z.D. Shi

    2001-01-01

    Shear-extrusion process and its forming parameters are proposed, whilst its laborsae ing characteristic is utilized to forge large-size shutoff valve body on middle-due pre ss.This new process is intended for the manufacture of large-size forged tubular components with branches on middle-due press. Experiments are carried out and proeessing parameters are obtained regarding the shear-extrusion process of a large-size shutoff valve body. Deformation and metal flow in the shear-extrnsion process are investigated. In order to verify the laborsaving characteristic of this new procss some contrastive experiments of extrusion foree are performed between shear-extrusion and upsetting-extrusion for forming tubular components with branches. Based on rigidplastic FEM a plane-strain model is established to analyze shear-extrusion process of tubular components with branches. The analysis results by 2-dimensions FEM are comparatively quite well consistent with those of experiments. Both simulated anl etperimental results show that this new forming process is feasible for forging large-size tubular components with branches on middle-due press.

  18. Influence of macromolecular architecture on necking in polymer extrusion film casting process

    International Nuclear Information System (INIS)

    Extrusion film casting (EFC) is an important polymer processing technique that is used to produce several thousand tons of polymer films/coatings on an industrial scale. In this research, we are interested in understanding quantitatively how macromolecular chain architecture (for example long chain branching (LCB) or molecular weight distribution (MWD or PDI)) influences the necking and thickness distribution of extrusion cast films. We have used different polymer resins of linear and branched molecular architecture to produce extrusion cast films under controlled experimental conditions. The necking profiles of the films were imaged and the velocity profiles during EFC were monitored using particle tracking velocimetry (PTV) technique. Additionally, the temperature profiles were captured using an IR thermography and thickness profiles were calculated. The experimental results are compared with predictions of one-dimensional flow model of Silagy et al1 wherein the polymer resin rheology is modeled using molecular constitutive equations such as the Rolie-Poly (RP) and extended Pom Pom (XPP). We demonstrate that the 1-D flow model containing the molecular constitutive equations provides new insights into the role of macromolecular chain architecture on film necking.1D. Silagy, Y. Demay, and J-F. Agassant, Polym. Eng. Sci., 36, 2614 (1996)

  19. Influence of macromolecular architecture on necking in polymer extrusion film casting process

    Energy Technology Data Exchange (ETDEWEB)

    Pol, Harshawardhan; Banik, Sourya; Azad, Lal Busher; Doshi, Pankaj; Lele, Ashish [CSIR-National Chemical Laboratory, Pune, Maharashtra (India); Thete, Sumeet [Purdue University, West Lafayette, Indiana (United States)

    2015-05-22

    Extrusion film casting (EFC) is an important polymer processing technique that is used to produce several thousand tons of polymer films/coatings on an industrial scale. In this research, we are interested in understanding quantitatively how macromolecular chain architecture (for example long chain branching (LCB) or molecular weight distribution (MWD or PDI)) influences the necking and thickness distribution of extrusion cast films. We have used different polymer resins of linear and branched molecular architecture to produce extrusion cast films under controlled experimental conditions. The necking profiles of the films were imaged and the velocity profiles during EFC were monitored using particle tracking velocimetry (PTV) technique. Additionally, the temperature profiles were captured using an IR thermography and thickness profiles were calculated. The experimental results are compared with predictions of one-dimensional flow model of Silagy et al{sup 1} wherein the polymer resin rheology is modeled using molecular constitutive equations such as the Rolie-Poly (RP) and extended Pom Pom (XPP). We demonstrate that the 1-D flow model containing the molecular constitutive equations provides new insights into the role of macromolecular chain architecture on film necking.{sup 1}D. Silagy, Y. Demay, and J-F. Agassant, Polym. Eng. Sci., 36, 2614 (1996)

  20. Solute distribution in columnar crystal zone of continuous casting billets

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The periodic bending deformation in the direction of casting occurs at the liquid/solid interface of billet due to the roller supporting force and the pressure of molten metal in the process of continuous casting. Based on this fact, a qualitative expression of solute concentration in columnar crystal zone for continuous casting billet is established, which agrees with the experimental results basically. Therefore, it is favorable to gain a columnar structure with less segregation by adopting a caster with compactly distributed small rollers and enhancing the cooling intensity in secondary-cooling zone.

  1. Meltlets® of soy isoflavones: Process optimization and the effect of extrusion spheronization process parameters on antioxidant activity

    Directory of Open Access Journals (Sweden)

    Ketkee Deshmukh

    2013-01-01

    Full Text Available In the current research work an attempt was made to develop ′′Melt in mouth pellets′′ (Meltlets® containing 40% herbal extract of soy isoflavones that served to provide antioxidants activity in menopausal women. The process of extrusion-spheronization was optimized for extruder speed, extruder screen size, spheronization speed, and time. While doing so the herbal extract incorporated in the pellet matrix was subjected to various processing conditions such as the effect of the presence of other excipients, mixing or kneading to prepare wet mass, heat generated during the process of extrusion, spheronization, and drying. Thus, the work further investigates the effect of these processing parameters on the antioxidant activity of the soy isoflavone herbal extract incorporated in the formula. Thereby, the antioxidant activity of the soya bean herbal extract, Meltlets® and of the placebo pellets was evaluated using DPPH free radical scavenging assay and total reduction capacity.

  2. Meltlets(®) of soy isoflavones: process optimization and the effect of extrusion spheronization process parameters on antioxidant activity.

    Science.gov (United States)

    Deshmukh, Ketkee; Amin, Purnima

    2013-07-01

    In the current research work an attempt was made to develop "Melt in mouth pellets" (Meltlets(®)) containing 40% herbal extract of soy isoflavones that served to provide antioxidants activity in menopausal women. The process of extrusion-spheronization was optimized for extruder speed, extruder screen size, spheronization speed, and time. While doing so the herbal extract incorporated in the pellet matrix was subjected to various processing conditions such as the effect of the presence of other excipients, mixing or kneading to prepare wet mass, heat generated during the process of extrusion, spheronization, and drying. Thus, the work further investigates the effect of these processing parameters on the antioxidant activity of the soy isoflavone herbal extract incorporated in the formula. Thereby, the antioxidant activity of the soya bean herbal extract, Meltlets(®) and of the placebo pellets was evaluated using DPPH free radical scavenging assay and total reduction capacity. PMID:24302800

  3. Meltlets® of Soy Isoflavones: Process Optimization and the Effect of Extrusion Spheronization Process Parameters on Antioxidant Activity

    OpenAIRE

    Ketkee Deshmukh; Purnima Amin

    2013-01-01

    In the current research work an attempt was made to develop ′′Melt in mouth pellets′′ (Meltlets® ) containing 40% herbal extract of soy isoflavones that served to provide antioxidants activity in menopausal women. The process of extrusion-spheronization was optimized for extruder speed, extruder screen size, spheronization speed, and time. While doing so the herbal extract incorporated in the pellet matrix was subjected to various processing conditions such as the effect of the presence of ot...

  4. Fractal characteristics of surface crack evolution in the process of gas-containing coal extrusion

    Institute of Scientific and Technical Information of China (English)

    Chen Peng; Wang Enyuan; Ou Jianchun; Li Zhonghui; Wei Mingyao; Li Xuelong

    2013-01-01

    In this paper,simulated experiment device of coal and gas outburst was employed to perform the experiment on gas-containing coal extrusion.In the experiment,coal surface cracks were observed with a highspeed camera and then the images were processed by sketch.Based on the above description,the paper studied the fractal dimension values from different positions of coal surface as well as their changing laws with time.The results show that there is a growing parabola treen of crack dimension value in the process of coal extrusion.Accordingly,we drew the conclusion that extruded coal crack evolution is a process of fractal dimension value increase.On the basis of factal dimension values taken from different parts of coal masses,a fractal dimension of the contour map was drawn.Thus,it is clear that the contour map involves different crack fractal dimension values from different positions.To be specific,where there are complicated force and violent movement In coal mass,there are higher fractal dimension values,i.e.,the further the middle of observation surface is from the exit of coal mass,and the lower the fractal dimension value is.In line with fractal geometry and energy theory of coal and gas outburst,this study presents the relation between fractal dimension and energy in the process of extruding.In conclusion,the evolution of crack fractal dimension value can signify that of energy,which has laid a solid foundation for the quantification research on the mechanism of gas-containing coal extrusion.

  5. Effects of popping and extrusion processes on some hydration properties of amaranth

    Directory of Open Access Journals (Sweden)

    González R.J.

    2002-01-01

    Full Text Available The effects of popping and extrusion processes on some of the hydration properties of Amarantus cruentus, which had already been degermed and dehulled, are discussed. Response surface methodology was used to analyse the effect of process variables (temperature and moisture on hydration properties, evaluated by water solubility (S and by amylographic retrogradation (R . Results show that precooked flours obtained by popping have a very high suspension consistency with low or intermediate S, while those obtained by extrusion have very high S but a much lower suspension consistency. The high S values for extruded samples are even higher than those for extruded waxy types of cereals. The effects of the variables on each response depend on each case. S increases as temperature (T and moisture (M increase in both processes, although in extrusion, a maximum value was observed at 200 masculineC and about 15% M. On the other hand, an inverse variable effect is observed for R; a minimum value is observed with extruded samples at about 14% M and for the whole T range, while a typical saddle-shaped surface is obtained for popped samples, with maximum values found at about 14 % and 18 % M for the two extreme T values, the highest and lowest, respectively. Another interesting effect is that the S-R pair values corresponding to popped samples do not fit the correlation between S and R, normally found with extruded samples. We can conclude that with the application of both processes it is possible to obtain precooked flours that have a wide range of hydration properties.

  6. Well-posedness and exact controllability of the mass balance equations for an extrusion process

    Science.gov (United States)

    Diagne, Mamadou; Shang, Peipei; Wang, Zhiqiang

    2016-07-01

    In this paper, we study the well-posedness and exact controllability of a physical model for a food extrusion process in the isothermal case. The model expresses the mass balance in the extruder chamber and consists of a hyperbolic Partial Differential Equation (PDE) and a nonlinear Ordinary Differential Equation (ODE) whose dynamics describes the evolution of a moving interface. By suitable change of coordinates and fixed point arguments, we prove the existence, uniqueness and regularity of the solution, and finally the exact controllability of the coupled system.

  7. Robotic extrusion processes for direct ink writing of 3D conductive polyaniline structures

    Science.gov (United States)

    Holness, F. Benjamin; Price, Aaron D.

    2016-04-01

    The intractable nature of intrinsically conductive polymers (ICP) leads to practical limitations in the fabrication of ICP-based transducers having complex three-dimensional geometries. Conventional ICP device fabrication processes have focused primarily on thin-film deposition techniques; therefore this study explores novel additive manufacturing processes specifically developed for ICP with the ultimate goal of increasing the functionality of ICP sensors and actuators. Herein we employ automated polymer paste extrusion processes for the direct ink writing of 3D conductive polyaniline (PANI) structures. Realization of these structures is enabled through a modified fused filament fabrication delta robot equipped with an integrated polymer paste extruder. This unique robot-controlled additive manufacturing platform is capable of fabricating high-resolution 3D conductive PANI and has been utilized to produce structures with a minimum feature size of 1.5 mm. The required processability of PANI is achieved by means of a counter-ion induced thermal doping method. Using this method, a viscous paste is formulated as the extrudate and a thermo-chemical treatment is applied post extrusion to finalize the complexation.

  8. Development of Replacements for Phoscoating Used in Forging, Extrusion and Metal Forming Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kerry Barnett

    2003-03-01

    Many forging, extrusion, heading and other metal forming processes use graphite-based lubricants, phosphate coatings, and other potentially hazardous or harmful substances to improve the tribology of the metal forming process. The application of phosphate-based coatings has long been studied to determine if other synthetic ''clean'' lubricants could provide the same degree of protection afforded by phoscoatings and its formulations. So far, none meets the cost and performance objectives provided by phoscoatings as a general aid to the metal forming industry. In as much as phoscoatings and graphite have replaced lead-based lubricants, the metal forming industry has had previous experience with a legislated requirement to change processes. However, without a proactive approach to phoscoating replacement, many metal forming processes could find themselves without a cost effective tribology material necessary for the metal forming process

  9. Application of powder injection moulding and extrusion process to manufacturing of Ni-YSZ anodes

    Directory of Open Access Journals (Sweden)

    G. Matula

    2009-09-01

    Full Text Available Purpose: Investigation of the Ni-YSZ cermets for anode supported solid oxide fuel cells (SOFC prepared by extrusion or powder injection moulding process, sintered and reduced of NiO-YSZ. Design/methodology/approach: Density examination, shrinkage examination, transverse rupture strength tests, microstructure examination.Findings: Results of the rheological and torque investigations have essential importance for further search of the optimum feedstock to injection moulding machines and extruders making forming possible of shapes for fuel cells anodes, which require in addition debinding of the binder, sintering, and reduction.Practical implications: The proposed technological solutions for fabricating anodes as tubes or flat shapes will make connecting the cells into packets possible which will allow increasing the cell power.Originality/value: The presented investigation results confirm purposefulness of employing injection moulding or extrusion for fabrication of fuel cells anodes. These two methods are used for manufacturing elements of devices in a mass scale. Significant interest in fuel cells and rapid development of their production which should take place in the close future may be the reason for searching the inexpensive technological solutions in the manufacturing process of the cells.

  10. The Influence of Segregation Phenomena on Quality of Product in Extrusion Process

    Directory of Open Access Journals (Sweden)

    G. Skorulski

    2010-07-01

    Full Text Available The segregation phenomena and formation of agglomerate have the basic influence on structure of the final product. The aim of this workis analyzing the phenomena of segregation in semi-solid extrusion process, using several kind of substitute materials, which can simulate the thixotrophic fluid behavior and displacement of solid particles. The experimental researches are made to investigation of segregation in the near-wall layers and the formation of agglomerate. Especially, the distribution of the solid particles at the end of extrusion process have been taken into consideration. Theoretical criteria describe the critical value of the energy liberated at the surfaces by the action of forces depends on the temperature, the pressure, the yield stress and the physical state and degree of intimacy of the contacting surfaces. The theory has been tested experimentally using a silicon polymer as a substitute material. Experimental stand with a Plexiglass die was prepared, such that the velocity fields at the surfaces could be observed and measured during plastic flow, allowing the empirical coefficients in the mathematical formulation to be estimated. On the basis of the theory and experiment an optimal die chamber was designed for a die with a complex shape.

  11. Possibility of Alternaria toxins reduction by extrusion processing of whole wheat flour.

    Science.gov (United States)

    Janić Hajnal, Elizabet; Čolović, Radmilo; Pezo, Lato; Orčić, Dejan; Vukmirović, Đuro; Mastilović, Jasna

    2016-12-15

    This study represents the first report about possibility of reduction of Alternaria toxins in wheat using the extrusion process. Effects of extrusion processing parameters - moisture content (w=16, 20, 24g/100g), feeding rate (q=15, 20, 25kg/h), and screw speed (v=300, 390, 480rpm), on reduction rate of tenuazonic acid (TeA), alternariol (AOH) and alternariol monomethyl ether (AME), in whole wheat flour were investigated. Temperature ranged between 111.1 and 160.8°C, while the absolute pressure was from 0.17 to 0.23MPa. The simultaneous influence of w and v was the most important for TeA reduction (p<0.05), while v and q were the most influential for AOH reduction (p<0.01). Level of AME reduction was mostly influenced by w and v (p<0.10). Optimal parameters for reduction of all three Alternaria toxins were as follows: w=24g/100g, q=25kg/h, v=390rpm, with a reduction of 65.6% for TeA, 87.9% for AOH and 94.5% for AME. PMID:27451248

  12. 昆钢70高碳钢炼钢工艺优化及铸坯质量分析%Research of billet quality and optimization of steel-making process for 70 high-carbon steel in KISC

    Institute of Scientific and Technical Information of China (English)

    张卫强; 陈伟; 李金柱

    2012-01-01

    To improve quality of product the steel making process of 70 high-carbon steel in KISC is optimized and improved and the macrostructure and index of central carbon segregation in the billet are analyzed by sampling. In the meanwhile inclusions in the billet are researched by using large sample electrolysis, scanning electron microscopy and spectroscopy test. The results show that quality of billet is improved significantly after process optimization, defect level of macrostructure for the most 71) high-carbon steel bil- lets is less than 0. 5 grade,ratio of equiaxed zone for the billet is more than 40 % ;index of central carbon segregation in billet is decreased from 1.06 to 1.03 and segregation of chemical compositions is small. The total amount of inclusions in 10 kg large sample e- lectrolysis is reduced from 28.95 mg to 9.78 mg and the inclusions are mainly composed of SiO2-A1203-CaO and SiO2-MnO-A1203 with low melting point and good plastic. The drawing break ratio of wire rod in one hundred tons is decreased from 7. 5 times to 4. 9 times and the drawing performance of wire rod is improved obviously.%为改善产品质量,武钢集团昆明钢铁股份有限公司对70钢炼钢工艺进行了优化改进,对铸坯取样进行了低倍组织、中心碳偏析检验分析,对夹杂物进行了大样电解、扫描电镜及能谱检验分析。结果表明:工艺优化后,70高碳硬线钢铸坯质量显著改善,低倍组织大部份缺陷级别不大于0.5级,铸坯中心等轴晶面积比率大于40%;铸坯中心碳偏析指数由1.06降至1.03,成分偏析减小;111kg铸坯大样电解夹杂物总量由28.95g降至9.78mg,夹杂物以低熔点的锰铝榴石、硅铝酸钙塑性夹杂为主;盘条拉拔断丝率南每百吨7.5次降至4.9次,拉拔性能显著改善。

  13. Obtaining Ready-to-Eat Blue Corn Expanded Snacks with Anthocyanins Using an Extrusion Process and Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Anayansi Escalante-Aburto

    2014-12-01

    Full Text Available Extrusion is an alternative technology for the production of nixtamalized products. The aim of this study was to obtain an expanded nixtamalized snack with whole blue corn and using the extrusion process, to preserve the highest possible total anthocyanin content, intense blue/purple coloration (color b and the highest expansion index. A central composite experimental design was used. The extrusion process factors were: feed moisture (FM, 15%–23%, calcium hydroxide concentration (CHC, 0%–0.25% and final extruder temperature (T, 110–150 °C. The chemical and physical properties evaluated in the extrudates were moisture content (MC, %, total anthocyanins (TA, mg·kg−1, pH, color (L, a, b and expansion index (EI. ANOVA and surface response methodology were applied to evaluate the effects of the extrusion factors. FM and T significantly affected the response variables. An optimization step was performed by overlaying three contour plots to predict the best combination region. The extrudates were obtained under the following optimum factors: FM (% = 16.94, CHC (% = 0.095 and T (°C = 141.89. The predicted extrusion processing factors were highly accurate, yielding an expanded nixtamalized snack with 158.87 mg·kg−1 TA (estimated: 160 mg·kg−1, an EI of 3.19 (estimated: 2.66, and color parameter b of −0.44 (estimated: 0.10.

  14. Final Technical Report - Advanced Optical Sensors to Minimize Energy Consumption in Polymer Extrusion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Susan J. Foulk

    2012-07-24

    Project Objective: The objectives of this study are to develop an accurate and stable on-line sensor system to monitor color and composition on-line in polymer melts, to develop a scheme for using the output to control extruders to eliminate the energy, material and operational costs of off-specification product, and to combine or eliminate some extrusion processes. Background: Polymer extrusion processes are difficult to control because the quality achieved in the final product is complexly affected by the properties of the extruder screw, speed of extrusion, temperature, polymer composition, strength and dispersion properties of additives, and feeder system properties. Extruder systems are engineered to be highly reproducible so that when the correct settings to produce a particular product are found, that product can be reliably produced time after time. However market conditions often require changes in the final product, different products or grades may be processed in the same equipment, and feed materials vary from lot to lot. All of these changes require empirical adjustment of extruder settings to produce a product meeting specifications. Optical sensor systems that can continuously monitor the composition and color of the extruded polymer could detect process upsets, drift, blending oscillations, and changes in dispersion of additives. Development of an effective control algorithm using the output of the monitor would enable rapid corrections for changes in materials and operating conditions, thereby eliminating most of the scrap and recycle of current processing. This information could be used to identify extruder systems issues, diagnose problem sources, and suggest corrective actions in real-time to help keep extruder system settings within the optimum control region. Using these advanced optical sensor systems would give extruder operators real-time feedback from their process. They could reduce the amount of off-spec product produced and

  15. On the influence of human factor on mechanical properties in aluminium hot extrusion process

    Directory of Open Access Journals (Sweden)

    I. Peruš

    2010-04-01

    Full Text Available A non-parametric model was proposed for modelling the influence of different technological and chemical parameters on the mechanical properties of the 6082 aluminium alloys during the hot extrusion process with a special consideration of human factor. It was shown that human factor (influence of process engineers was important and that it could be efficiently modeled and taken into account by the proposed Conditional Average Estimator (CAE method. Production might be improved (optimized by a proper education and/or by eliminating critical process engineers. It was found that the highest values for elongation and yield stress did not coincide with the range of the most frequent combinations of input parameters.

  16. Effect of extrusion processing on the microstructure, mechanical properties, biocorrosion properties and antibacterial properties of Ti-Cu sintered alloys.

    Science.gov (United States)

    Zhang, Erlin; Li, Shengyi; Ren, Jing; Zhang, Lan; Han, Yong

    2016-12-01

    Ti-Cu sintered alloys, Ti-Cu(S) alloy, have exhibited good anticorrosion resistance and strong antibacterial properties, but low ductility in previous study. In this paper, Ti-Cu(S) alloys were subjected to extrusion processing in order to improve the comprehensive property. The phase constitute, microstructure, mechanical property, biocorrosion property and antibacterial activity of the extruded alloys, Ti-Cu(E), were investigated in comparison with Ti-Cu(S) by X-ray diffraction (XRD), optical microscopy (OM), scanning electronic microscopy (SEM) with energy disperse spectroscopy (EDS), mechanical testing, electrochemical testing and plate-count method in order to reveal the effect of the extrusion process. XRD, OM and SEM results showed that the extrusion process did not change the phase constitute but refined the grain size and Ti2Cu particle significantly. Ti-Cu(E) alloys exhibited higher hardness and compressive yield strength than Ti-Cu(S) alloys due to the fine grain and Ti2Cu particles. With the consideration of the total compressive strain, it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S) alloys. Electrochemical results have indicated that the extrusion process improved the corrosion resistance of Ti-Cu(S) alloys. Plate-count method displayed that both Ti-Cu(S) and Ti-Cu(E) exhibited strong antibacterial activity (>99%) against S. aureus. All these results demonstrated that hot forming processing, such as the extrusion in this study, refined the microstructure and densified the alloy, in turn improved the ductility and strength as well as anticorrosion properties without reduction in antibacterial properties.

  17. Effect of extrusion processing on the microstructure, mechanical properties, biocorrosion properties and antibacterial properties of Ti-Cu sintered alloys.

    Science.gov (United States)

    Zhang, Erlin; Li, Shengyi; Ren, Jing; Zhang, Lan; Han, Yong

    2016-12-01

    Ti-Cu sintered alloys, Ti-Cu(S) alloy, have exhibited good anticorrosion resistance and strong antibacterial properties, but low ductility in previous study. In this paper, Ti-Cu(S) alloys were subjected to extrusion processing in order to improve the comprehensive property. The phase constitute, microstructure, mechanical property, biocorrosion property and antibacterial activity of the extruded alloys, Ti-Cu(E), were investigated in comparison with Ti-Cu(S) by X-ray diffraction (XRD), optical microscopy (OM), scanning electronic microscopy (SEM) with energy disperse spectroscopy (EDS), mechanical testing, electrochemical testing and plate-count method in order to reveal the effect of the extrusion process. XRD, OM and SEM results showed that the extrusion process did not change the phase constitute but refined the grain size and Ti2Cu particle significantly. Ti-Cu(E) alloys exhibited higher hardness and compressive yield strength than Ti-Cu(S) alloys due to the fine grain and Ti2Cu particles. With the consideration of the total compressive strain, it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S) alloys. Electrochemical results have indicated that the extrusion process improved the corrosion resistance of Ti-Cu(S) alloys. Plate-count method displayed that both Ti-Cu(S) and Ti-Cu(E) exhibited strong antibacterial activity (>99%) against S. aureus. All these results demonstrated that hot forming processing, such as the extrusion in this study, refined the microstructure and densified the alloy, in turn improved the ductility and strength as well as anticorrosion properties without reduction in antibacterial properties. PMID:27612770

  18. An investigation on diffusion bonding of aluminum to copper using equal channel angular extrusion process.

    Science.gov (United States)

    Eslami, P; Taheri, A Karimi

    2011-06-30

    A new method for production of bimetallic rods, utilizing the equal channel angular extrusion (ECAE) process has been introduced before by previous researchers, but no attempt has been made to assess the effect of different temperatures and holding times in order to achieve a diffusional bond between the mating surfaces. In present research copper sheathed aluminum rods have been ECAEed at room temperature and subsequently held at a constant ECAE pressure, at different temperatures and holding times to produce a diffusional bond between the copper sheath and the aluminum core. The bonding quality of the joints was examined by shear strength test and a sound bonding interface was achieved. Based on the results, a bonding temperature of 200 °C and holding time of 60-80 min yielded the highest shear strength value. PMID:21760654

  19. Manufacture of porous biodegradable polymer conduits by an extrusion process for guided tissue regeneration

    Science.gov (United States)

    Widmer, M. S.; Gupta, P. K.; Lu, L.; Meszlenyi, R. K.; Evans, G. R.; Brandt, K.; Savel, T.; Gurlek, A.; Patrick, C. W. Jr; Mikos, A. G.; McIntire, L. V. (Principal Investigator)

    1998-01-01

    We have fabricated porous, biodegradable tubular conduits for guided tissue regeneration using a combined solvent casting and extrusion technique. The biodegradable polymers used in this study were poly(DL-lactic-co-glycolic acid) (PLGA) and poly(L-lactic acid) (PLLA). A polymer/salt composite was first prepared by a solvent casting process. After drying, the composite was extruded to form a tubular construct. The salt particles in the construct were then leached out leaving a conduit with an open-pore structure. PLGA was studied as a model polymer to analyze the effects of salt weight fraction, salt particle size, and processing temperature on porosity and pore size of the extruded conduits. The porosity and pore size were found to increase with increasing salt weight fraction. Increasing the salt particle size increased the pore diameter but did not affect the porosity. High extrusion temperatures decreased the pore diameter without altering the porosity. Greater decrease in molecular weight was observed for conduits manufactured at higher temperatures. The mechanical properties of both PLGA and PLLA conduits were tested after degradation in vitro for up to 8 weeks. The modulus and failure strength of PLLA conduits were approximately 10 times higher than those of PLGA conduits. Failure strain was similar for both conduits. After degradation for 8 weeks, the molecular weights of the PLGA and PLLA conduits decreased to 38% and 43% of the initial values, respectively. However, both conduits maintained their shape and did not collapse. The PLGA also remained amorphous throughout the time course, while the crystallinity of PLLA increased from 5.2% to 11.5%. The potential of seeding the conduits with cells for transplantation or with biodegradable polymer microparticles for drug delivery was also tested with dyed microspheres. These porous tubular structures hold great promise for the regeneration of tissues which require tubular scaffolds such as peripheral nerve

  20. Study on the Hot Extrusion Process of Advanced Radiation Resistant Oxide Dispersion Strengthened Steel Tubes

    International Nuclear Information System (INIS)

    Ferritic/martensitic steel has a better thermal conductivity and swelling resistance than austenitic stainless steel. Unfortunately, the available temperature range of ferritic/martensitic steel is limited at up to 650 .deg. C. Oxide dispersion strengthened (ODS) steels have been developed as the most prospective core structural materials for next generation nuclear systems because of their excellent high strength and irradiation resistance. The material performances of this new alloy are attributed to the existence of uniformly distributed nano-oxide particles with a high density, which is extremely stable at high temperature in a ferritic/martensitic matrix. This microstructure can be very attractive in achieving superior mechanical properties at high temperatures, and thus, these favorable microstructures should be obtained through the controls of the fabrication process parameters during the mechanical alloying and hot consolidation procedures. In this study, a hot extrusion process for advanced radiation resistant ODS steel tube was investigated. ODS martensitic steel was designed to have high homogeneity, productivity, and reproducibility. Mechanical alloying and hot consolidation processes were employed to fabricate the ODS steels. A microstructure observation and creep rupture test were examined to investigate the effects of the optimized fabrication conditions. Advanced radiation resistant ODS steel has been designed to have homogeneity, productivity, and reproducibility. For these characteristics, modified mechanical alloying and hot consolidation processes were developed. Microstructure observation revealed that the ODS steel has uniformly distributed fine-grain nano-oxide particles. The fabrication process for the tubing is also being propelled in earnest

  1. Microstructure evolution of processed Mg-Al-Zn alloy by equal channel angular extrusion in semi-solid isothermal treatment

    Institute of Scientific and Technical Information of China (English)

    JIANG Ju-fu; LUO Shou-jing

    2006-01-01

    Microstructure evolution of processed Mg-Al-Zn alloy by equal channel angular extrusion(ECAE) in semi-solid isothermal treatment was investigated. The results show that with increasing semi-solid isothermal treatment temperature, the α phase solid grain size of processed Mg-Al-Zn alloy by ECAE increases firstly due to coarsening of α phase solid grains, then decreases due to melting of α phase solid grains. With the increase of extrusion passes during ECAE, the α phase solid grain size in the following semi-solid isothermal treatment decreases. The α phase solid grain size of processed Mg-Al-Zn alloy by ECAE under route BC is the smallest, while the α phase solid grain size of processed material by ECAE under route A is the largest. The primary mechanism of spheroid formation depends on the melting of recrystallizing boundaries and diffusion of solute atoms in the semi-solid state.

  2. Analysis of Solid State Bonding in the Extrusion Process of Magnesium Alloys --Numerical Prediction and Experimental Verification

    Science.gov (United States)

    Alharthi, Nabeel H.

    The automotive industry developments focused on increasing fuel efficiency are accomplished by weight reduction of vehicles, which consequently results in less negative environmental impact. Usage of low density materials such as Magnesium alloys is an approach to replace heavier structural components. One of the challenges in deformation processing of Magnesium is its low formability attributed to the hexagonal close packed (hcp) crystal structure. The extrusion process is one of the most promising forming processes for Magnesium because it applies a hydrostatic compression state of stress during deformation resulting in improved workability. Many researchers have attempted to fully understand solid state bonding during deformation in different structural materials such as Aluminum, Copper and other metals and alloys. There is a lack of sufficient understanding of the extrusion welding in these materials as well as very limited knowledge on this subject for hollow profiles made from Magnesium alloys. The weld integrity and the characteristic of the welding microstructure are generally unknown. In this dissertation three related research projects are investigated by using different tools such as microstructure characterization, mechanical testing, thermo-mechanical physical simulation and finite element numerical modeling. Project 1: Microstructure characterization supported by mechanical testing of the extrusion welding regions in Magnesium alloy AM30 extrudate. The microstructure characterization was conducted using Light Optical Microscopy (LOM), in addition to LOM the electron backscattered diffraction (EBSD) technique was implemented to characterize in depth the deformed and welded microstructure. Project 2: Finite element numerical simulation of AM30 extrudate to model different process parameters and their influence on localized state variables such as strain, strain rate, temperature and normal pressure within the weld zone. Project 3: Physical simulation

  3. Novel Controlled Release Polymer-Lipid Formulations Processed by Hot Melt Extrusion.

    Science.gov (United States)

    Maniruzzaman, Mohammed; Islam, Muhammad T; Halsey, Sheelagh; Amin, Devyani; Douroumis, Dennis

    2016-02-01

    The aim of the study was to investigate the effect of novel polymer/lipid formulations on the dissolution rates of the water insoluble indomethacin (INM), co-processed by hot melt extrusion (HME). Formulations consisted of the hydrophilic hydroxypropyl methyl cellulose polymer (HPMCAS) and stearoyl macrogol-32 glycerides-Gelucire 50/13 (GLC) were processed with a twin screw extruder to produce solid dispersions. The extrudates characterized by X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and hot stage microscopy (HSM) indicated the presence of amorphous INM within the polymer/lipid matrices. In-line monitoring via near-infrared (NIR) spectroscopy revealed significant peak shifts indicating possible interactions and H-bonding formation between the drug and the polymer/lipid carriers. Furthermore, in vitro dissolution studies showed a synergistic effect of the polymer/lipid carrier with 2-h lag time in acidic media followed by enhanced INM dissolution rates at pH > 5.5.

  4. The reactive extrusion of thermoplastic polyurethane

    OpenAIRE

    Verhoeven, Vincent Wilhelmus Andreas

    2006-01-01

    The objective of this thesis was to increase the understanding of the reactive extrusion of thermoplastic polyurethane. Overall, several issues were identified: • Using a relative simple extrusion model, the reactive extrusion process can be described. This model can be used to further investigate and optimize the reactive extrusion of thermoplastic polyurethane. • Premixing has a small beneficiary effect on the efficiency of the extrusion process and the quality of the product formed. • The ...

  5. Continuously graded extruded polymer composites for energetic applications fabricated using twin-screw extrusion processing technology

    Science.gov (United States)

    Gallant, Frederick M.

    A novel method of fabricating functionally graded extruded composite materials is proposed for propellant applications using the technology of continuous processing with a Twin-Screw Extruder. The method is applied to the manufacturing of grains for solid rocket motors in an end-burning configuration with an axial gradient in ammonium perchlorate volume fraction and relative coarse/fine particle size distributions. The fabrication of functionally graded extruded polymer composites with either inert or energetic ingredients has yet to be investigated. The lack of knowledge concerning the processing of these novel materials has necessitated that a number of research issues be addressed. Of primary concern is characterizing and modeling the relationship between the extruder screw geometry, transient processing conditions, and the gradient architecture that evolves in the extruder. Recent interpretations of the Residence Time Distributions (RTDs) and Residence Volume Distributions (RVDs) for polymer composites in the TSE are used to develop new process models for predicting gradient architectures in the direction of extrusion. An approach is developed for characterizing the sections of the extrudate using optical, mechanical, and compositional analysis to determine the gradient architectures. The effects of processing on the burning rate properties of extruded energetic polymer composites are characterized for homogeneous formulations over a range of compositions to determine realistic gradient architectures for solid rocket motor applications. The new process models and burning rate properties that have been characterized in this research effort will be the basis for an inverse design procedure that is capable of determining gradient architectures for grains in solid rocket motors that possess tailored burning rate distributions that conform to user-defined performance specifications.

  6. Numerical and experimental investigation of central cavity formation in aluminum during forward extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, S. H.; Sedighi, M.; Mosayebnezhad, J. [Iran Univ., Tehran (Iran, Islamic Republic of)

    2016-05-15

    In the presented paper central cavity formation during the forward extrusion of commercially pure aluminum was investigated. For this purpose finite element analysis was utilized for simulation of this defect. The experimental tests were carried out on commercially pure aluminum. A good agreement between finite element simulations and experimental tests verified the adaptability of finite element simulations with the real process conditions. Taguchi method was performed for classifying the simulations regarding to consider synergistic parameters. The parameters include reduction of area, friction coefficient and die angle. Critical thickness, the representative waste material, was presented as a new criterion for optimizing the parametric study. By utilizing the Analyze Taguchi design, critical thickness was optimized and the effect of each parameter was recognized for different levels. In addition, the best levels with the minimum waste material were gained in which friction coefficient, die angle and reduction of area were 0.2, 5 .deg. and 20%, respectively. Also the amount of waste material was forecasted by just about 2% errors without FEA by Taguchi method.

  7. Characterization of printed planar electromagnetic coils using digital extrusion and roll-to-roll flexographic processes

    Science.gov (United States)

    Rickard, Scott

    Electromagnets are a crucial component in a wide range of more complex electrical devices due to their ability to turn electrical energy into mechanical energy and vice versa. The trend for electronics becoming smaller and lighter has led to increased interest in using flat, planar electromagnetic coils, which have been shown to perform better at scaled down sizes. The two-dimensional geometry of a planar electromagnetic coil yields itself to be produced by a roll-to-roll additive manufacturing process. The emergence of the printed electronics field, which uses traditional printing processes to pattern functional inks, has led to new methods of mass-producing basic electrical components. The ability to print a planar electromagnetic coil using printed electronics could rival the traditional subtractive and semi-subtractive PCB process of manufacturing. The ability to print lightweight planar electromagnetic coils on flexible substrates could lead to their inclusion into intelligent packaging applications and could have specific use in actuating devices, transformers, and electromagnetic induction applications such as energy harvesting or wireless charging. In attempts to better understand the limitations of printing planar electromagnetic coils, the effect that the design parameters of the planar coils have on the achievable magnetic field strength were researched. A comparison between prototyping methods of digital extrusion and manufacturing scale flexographic printing are presented, discussing consistency in the printed coils and their performance in generating magnetic fields. A method to predict the performance of these planar coils is introduced to allow for design within required needs of an application. Results from the research include a demonstration of a printed coil being used in a flat speaker design, working off of actuating principles.

  8. Determination and implementation of polymer parameters into simulations of the twin-screw extrusion process.

    OpenAIRE

    Strandberg, Marcus

    2015-01-01

    This thesis was conducted in cooperation with a Swedish company that develops and manufactures plastic compounds. An increasing need for identifying material properties is seen within the industry in order to predict the outcome of the extrusion process by using simulations. The purpose of this study was to expand a material database with the results obtained through various measurements of the material parameters in order to enable simulations. The numerical descriptions would be analyzed an...

  9. Physicochemical and dissolution profile characterization of pellets containing different binders obtained by the extrusion-spheronization process

    OpenAIRE

    Michele Georges Issa; Letícia Pessole; Andrea Ikeda Takahashi; Newton Andréo Filho; Humberto Gomes Ferraz

    2012-01-01

    With the purpose of evaluating the behavior of different polymers employed as binders in small-diameter pellets for oral administration, we prepared formulations containing paracetamol and one of the following polymers: PVP, PEG 1500, hydroxypropylmethylcellulose and methylcellulose, and we evaluated their different binding properties. The pellets were obtained by the extrusion/spheronization process and were subsequently subjected to fluid bed drying. In order to assess drug delivery, the Un...

  10. Parallel assembling and equation solving via graph algorithms with an application to the FE simulation of metal extrusion processes

    CERN Document Server

    Unterkircher, A

    2005-01-01

    We propose methods for parallel assembling and iterative equation solving based on graph algorithms. The assembling technique is independent of dimension, element type and model shape. As a parallel solving technique we construct a multiplicative symmetric Schwarz preconditioner for the conjugate gradient method. Both methods have been incorporated into a non-linear FE code to simulate 3D metal extrusion processes. We illustrate the efficiency of these methods on shared memory computers by realistic examples.

  11. Consensus Control Design for 360 MN Extrusion Machine Producing Process

    Directory of Open Access Journals (Sweden)

    Chao Wang

    2014-01-01

    Full Text Available This paper mainly addresses the issue of 360 MN extrusion machine and focuses on the stabilization control of main table attitude. We will first introduce the problem and then model the extrusion machine. As the machine is a multi-input multioutput (MIMO and strong coupling system, it is challenging to apply existing control theory to design a controller to stabilize the main table attitude. Motivated by recent research in the field of multiagent systems, we design a consensus control protocol for our system and derive our convergence conditions based directly on Routh stability criterion. The advantages of the design are also demonstrated by numerical simulation.

  12. GRAPHITE EXTRUSIONS

    Science.gov (United States)

    Benziger, T.M.

    1959-01-20

    A new lubricant for graphite extrusion is described. In the past, graphite extrusion mixtures have bcen composed of coke or carbon black, together with a carbonaceous binder such as coal tar pitch, and a lubricant such as petrolatum or a colloidal suspension of graphite in glycerin or oil. Sinee sueh a lubricant is not soluble in, or compatible with the biiider liquid, such mixtures were difficult to extrude, and thc formed pieees lacked strength. This patent teaches tbe use of fatty acids as graphite extrusion lubricants and definite improvemcnts are realized thereby since the fatty acids are soluble in the binder liquid.

  13. Modelling and Validation of Synthesis of Poly Lactic Acid Using an Alternative Energy Source through a Continuous Reactive Extrusion Process

    Directory of Open Access Journals (Sweden)

    Satya P. Dubey

    2016-04-01

    Full Text Available PLA is one of the most promising bio-compostable and bio-degradable thermoplastic polymers made from renewable sources. PLA is generally produced by ring opening polymerization (ROP of lactide using the metallic/bimetallic catalyst (Sn, Zn, and Al or other organic catalysts in a suitable solvent. In this work, reactive extrusion experiments using stannous octoate Sn(Oct2 and tri-phenyl phosphine (PPh3 were considered to perform ROP of lactide. Ultrasound energy source was used for activating and/or boosting the polymerization as an alternative energy (AE source. Ludovic® software, designed for simulation of the extrusion process, had to be modified in order to simulate the reactive extrusion of lactide and for the application of an AE source in an extruder. A mathematical model for the ROP of lactide reaction was developed to estimate the kinetics of the polymerization process. The isothermal curves generated through this model were then used by Ludovic software to simulate the “reactive” extrusion process of ROP of lactide. Results from the experiments and simulations were compared to validate the simulation methodology. It was observed that the application of an AE source boosts the polymerization of lactide monomers. However, it was also observed that the predicted residence time was shorter than the experimental one. There is potentially a case for reducing the residence time distribution (RTD in Ludovic® due to the ‘liquid’ monomer flow in the extruder. Although this change in parameters resulted in validation of the simulation, it was concluded that further research is needed to validate this assumption.

  14. Fabrication of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) biocomposites with reinforcement by hydroxyapatite using extrusion processing.

    Science.gov (United States)

    Öner, Mualla; İlhan, Berna

    2016-08-01

    The aim of this study was to prepare poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHBV, biocomposites with incorporating various percentages of hydroxyapatite (HAP) using extrusion processing. The biocomposites were produced by melt extrusion of PHBV with untreated HAP and surface-treated HAP crystals. The structure of biopolymer/HAP biocomposites was investigated by XRD, FTIR, DSC and SEM. Silane coupling agent was used for HAP surface treatment in PHBV/HAP composites. Silane-treated HAP nanoparticles yielded nanocomposites characterized by good mechanical performance and fine nanofiller dispersion, as shown by SEM investigations. The Halpin-Tsai and Hui-Shia models were used to evaluate the effect of reinforcement by HAP particles on the elastic modulus of the composites. Micromechanical models for initial composite stiffness showed good correlation with experimental values. Disparities in the Halpin-Tsai model were evident for composite with higher HAP loadings. PMID:27157723

  15. Isolation and characterization of fish scale collagen from tilapia (Oreochromis sp.) by a novel extrusion-hydro-extraction process.

    Science.gov (United States)

    Huang, Chun-Yung; Kuo, Jen-Min; Wu, Shu-Jing; Tsai, Hsing-Tsung

    2016-01-01

    Collagen is highly valued both as a food additive and a functional food ingredient. It is generally extracted by treatments with acid or alkali, enzyme, and microorganisms. However these methods are generally batch type, time-, energy-, reactant-, and cost-consuming. Extrusion is widely used in the food industry, and offers many advantages, such as ease of operation, continuous production, high yield, and little waste. In this study, we developed a novel extrusion-hydro-extraction (EHE) process for extraction of collagen from tilapia fish scale. Extruded scale samples had a 2-3 times higher protein extraction yield than that of non-extruded scale samples. All extracts contained hydroxyproline (61-73 residues/1000 residues) and hydroxylysine (5-6 residues/1000 residues) and were identified as type-I collagens by FTIR, SDS-PAGE, and molecular weight distribution analyses. The physicochemical studies revealed that extracted collagens could have promising applications in the food, medical, and cosmetic industries. PMID:26213067

  16. Twins, recrystallization and texture evolution of a Mg-5.99Zn-1.76Ca-0.35Mn (wt.%) alloy during indirect extrusion process

    International Nuclear Information System (INIS)

    The microstructural evolution of a Mg-5.99Zn-1.76Ca-0.35Mn (wt.%) alloy during indirect extrusion at 350 oC was systematically examined by electron backscattering diffraction analysis. The {101-bar 2} extension twin played a dominant role in the formation of an undynamically recrystallized area and an extrusion basal fiber texture. Fine-grained structures were preferentially formed in the untwinned matrix and near the intermetallic compounds due to continuous dynamically recrystallization (DRX). The spacing between the fragmented compound bandings became smaller as the extrusion process proceeded, leading to a high DRX volume fraction of 98%.

  17. 连接杆热挤压工艺及模具设计%Hot Extrusion Process for Connecting Rod and Its Die Design

    Institute of Scientific and Technical Information of China (English)

    王国林; 聂兰启; 汪发春

    2011-01-01

    Through analyzing the structure of connecting rod, its hot extrusion process was introduced, and the connecting rod was produced by this process, then a composite extrusion process was put forward.The size of the die and the calculation method of hot extrusion force were presented, and the design of reshaping die, extruding hole die and hot extrusion die was introduced.%通过对连接杆结构进行分析,介绍了连接杆热挤压成形工艺方案,并进行了工艺试验,提出了采用棒料复合挤压成形连接杆工艺.给出了坯料尺寸及热挤压力的计算方法,并对整形模、挤孔模、热挤压模的设计做了介绍.

  18. UBET analysis of process of extruding aluminum alloy ribbed thin-wall pipes through a porthole die

    Institute of Scientific and Technical Information of China (English)

    谢建新; 裴强; 刘静安

    2002-01-01

    Using the upper bound element technique (UBET), a numerical model was proposed for analyzing the metal deformation behavior in the extrusion process of ribbed thin-wall pipes through a porthole die. Optimization parameters were contained in the numerical model and determined through minimizing the total work of metal deformation. Taking the extrusion process of thin-wall pipe with one rib as an example, the calculated results using the proposed model are as follows: the extrusion pressure p is linearly related to the extrusion ratio R by p = a+bR 0.683, where a =14.13, b =0.911. When the length of the billet remaining in container is shorter than a quarter of the container diameter, the plastic region extends over the whole of the remained billet and the extrusion process reaches the state of funnel deformation. There exists an optimum depth of welding chamber in respect of the extrusion pressure, and to the calculated example the optimum depth is about 10% of the circumscribed diameter of portholes. To obtain more equitable metal flow in welding chamber, it is required to make the dividing planes in container to be consistent with corresponding welding planes in the chamber ( θ max i = θ′ max i ) through choosing different entering area for each of the portholes.

  19. Properties and processing by extrusion of electrically conductive multilayer filaments comprising polymer composites

    OpenAIRE

    R. S. Martins; Gonçalves, Renato Ferreira; Azevedo, Tiago; Nóbrega, J. M.; Carvalho, Helder; Lanceros-Méndez, S.; Rocha, J. G.

    2013-01-01

    This work describes the production and characterization of three-layer piezoelectric filaments using two different electrically conductive polymers. The filaments were produced in a filament extrusion line, equipped with a coextrusion die that enabled a coaxial arrangement for a three-layer filament. For the inner and outer layers two different electrically conductive compounds were used, and the middle layer was made of the electroactive polymer PVDF. The produced filament can be used as a p...

  20. Hydrostatic extrusion of magnesium alloys

    NARCIS (Netherlands)

    Sillekens, W.H.; Bohlen, J.

    2012-01-01

    This chapter deals with the capabilities and limitations of the hydrostatic extrusion process for the manufacturing of magnesium alloy sections. Firstly, the process basics for the hydrostatic extrusion of materials in general and of magnesium in particular are introduced. Next, some recent research

  1. The numerical simulation of powder canning hot extrusion of W-4OCu alloy%W-40Cu粉末包套热挤压过程数值模拟

    Institute of Scientific and Technical Information of China (English)

    李达人; 蔡一湘; 王尔德

    2012-01-01

    采用DEFORM-2D软件对W-40Cu粉末包套热挤压过程进行了数值模拟,研究了挤压过程中内部多孔体粉末坯料和外部塑性钢套的温度场、应力应变场和速度场的分布情况,并深入分析了坯料的等效应力应变和坯料、包套的最大流动速度随挤压温度、挤压速度、挤压比等的变化情况,以及包套厚度对粉末包套热挤压过程的影响.结果表明:粉末包套挤压过程中在模口附近出现最高温度值,等效应力的最大值出现在锥形区转角处,等效应变最大值出现在模口附近的包套表面,坯料最大流动速度值出现在模口附近的坯料芯部位置,包套最大流速值出现在挤压头部位置;坯料等效应变和流动速度随包套壁厚的增加先升高后降低,在包套壁厚为7.5mm时应变值最高;包套底厚影响挤压坯的形状和材料利用率.模拟得到的不同温度和挤压比下的变形载荷与实验值误差小于10%,吻合较好.%Numerical simulation of W-40Cu powder canning hot extrusion was carried out by DEF0RM-2D. The distribution of temperature, stress/strain and velocity field either in the porous billet or plastic steel can were discussed. The variation of effective stress/strain and max flow speed of billets and steel can with extrusion temperature, extrusion speed, extrusion ratio and the effect of can thickness on hot extrusion process were also studied. The results show that, the flow speed of billets and steel can increases with the increasing extrusion speed and ratio. The effective strain and flow speed of billet first increase and then decrease with the increasing wall thickness of can, the shape and utilization ratio of porous billet are affected by bottom thickness of can. The simulative extrusion load with different extrusion temperature and ratio is in accord with experimental extrusion load.

  2. Preparation of Ceramic Composite Pipes Through Paste Extrusion

    Institute of Scientific and Technical Information of China (English)

    Zhongchun Chen; Takenobu Takeda; Keisuke Kikuchi

    2000-01-01

    An experimental investigation was carried out in order to prepare ceramic composite pipes used for tubular solid oxide fuel cells by using a multi-billet extrusion technique. Particular emphasis was given to the forming possibility and extrusion behavior of a two-layer pipe consisting of NiO-YSZ(PSZ) (anode) and YSZ (electrolyte). It is shown that the extrusion pressure and binder content required decrease with increasing the fraction of nickel oxide in the anode layers. The porosity in the anode layers depends on the binder content in pastes. It is feasible to prepare anode/electrolyte composite pipes by means of co-extrusion of different pastes.Furthermore, it is possible to obtain sound sintered pipes even under pressureless sintering conditions.

  3. Scale up tools in reactive extrusion and compounding processes. Could 1D-computer modeling be helpful?

    Science.gov (United States)

    Pradel, J.-L.; David, C.; Quinebèche, S.; Blondel, P.

    2014-05-01

    Industrial scale-up (or scale down) in Compounding and Reactive Extrusion processes is one of the most critical R&D challenges. Indeed, most of High Performances Polymers are obtained within a reactive compounding involving chemistry: free radical grafting, in situ compatibilization, rheology control... but also side reactions: oxidation, branching, chain scission... As described by basic Arrhenius and kinetics laws, the competition between all chemical reactions depends on residence time distribution and temperature. Then, to ensure the best possible scale up methodology, we need tools to match thermal history of the formulation along the screws from a lab scale twin screw extruder to an industrial one. This paper proposes a comparison between standard scale-up laws and the use of Computer modeling Software such as Ludovic® applied and compared to experimental data. Scaling data from a compounding line to another one, applying general rules (for example at constant specific mechanical energy), shows differences between experimental and computed data, and error depends on the screw speed range. For more accurate prediction, 1D-Computer Modeling could be used to optimize the process conditions to ensure the best scale-up product, especially in temperature sensitive reactive extrusion processes. When the product temperature along the screws is the key, Ludovic® software could help to compute the temperature profile along the screws and extrapolate conditions, even screw profile, on industrial extruders.

  4. Biodegradable polymer blends based on corn starch and thermoplastic chitosan processed by extrusion.

    Science.gov (United States)

    Mendes, J F; Paschoalin, R T; Carmona, V B; Sena Neto, Alfredo R; Marques, A C P; Marconcini, J M; Mattoso, L H C; Medeiros, E S; Oliveira, J E

    2016-02-10

    Blends of thermoplastic cornstarch (TPS) and chitosan (TPC) were obtained by melt extrusion. The effect of TPC incorporation in TPS matrix and polymer interaction on morphology and thermal and mechanical properties were investigated. Possible interactions between the starch molecules and thermoplastic chitosan were assessed by XRD and FTIR techniques. Scanning Electron Microscopy (SEM) analyses showed a homogeneous fracture surface without the presence of starch granules or chitosan aggregates. Although the incorporation of thermoplastic chitosan caused a decrease in both tensile strength and stiffness, films with better extensibility and thermal stability were produced. PMID:26686150

  5. Deformation division of metal flow behavior during extrusion process of 7075 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    LI Feng; CHU Guan-nan; LIU Xiao-jing

    2009-01-01

    To reduce defects caused by non-homogeneous metal flow in conventional extrusion, a die with guiding angle was designed to improve the metal flow behavior. The characteristic quantities such as the second invariant of the deviator stress J2 and Lode's coefficient p were employed for the division of deformation area. The results show that when the metal is extruded with the guiding angle, no metal flow interface forms at the container's bottom, the dead zone completely disappears, the deformation types of the metal in the plastic deformation area change from three types to one type of tension, and the homogeneity of the deformation as well as metal flow are greatly improved. The non-homogeneous metal flow at the final stage of extrusion is improved, reducing the shrinkage hole at the axis end. The radial stress of the furthest point from the axis is transformed from tensile stress to compressive stress and the axial stress, and decreased from 70.8 to 34.8 MPa. Therefore, the surface cracks caused by additional stress arc greatly reduced.

  6. Assessment of extrusion-sonication process on flame retardant polypropylene by rheological characterization

    Directory of Open Access Journals (Sweden)

    Guadalupe Sanchez-Olivares

    2016-05-01

    Full Text Available In this work, the rheological behavior of flame retardant polypropylene composites produced by two methods: 1 twin-screw extrusion and 2 ultrasound application combined with a static mixer die single-screw extrusion is analyzed in detail; results are related to the morphology of the composites. The flame retardant polymer composites are composed of a polypropylene matrix, an intumescent flame retardant system and functionalized clay. Scanning electron microscopy revealed that the combination of the static mixer die and on-line sonication reduced particle size and improved the dispersion and distribution of the intumescent additives in the polypropylene matrix at the micrometric level. From linear viscoelastic properties, the Han, Cole-Cole and van Gurp-Palmen diagrams characterized the improved particle dispersion of the flame retardant additives. Two well-defined rheological behaviors were observed in these diagrams. These behaviors are independent on clay presence and concentration. In fact, the ultrasound device generates a 3D highly interconnected structure similar to a co-continuous pattern observed in polymer blends as evidenced by rheological measurements. This improvement in the dispersion and distribution of the additives is attributed to the combined effect of the static mixer die and on-line sonication that allowed reducing the additive content while achieving the optimum classification UL94-V0.

  7. Process design and control of a twin screw hot melt extrusion for continuous pharmaceutical tamper-resistant tablet production.

    Science.gov (United States)

    Baronsky-Probst, J; Möltgen, C-V; Kessler, W; Kessler, R W

    2016-05-25

    Hot melt extrusion (HME) is a well-known process within the plastic and food industries that has been utilized for the past several decades and is increasingly accepted by the pharmaceutical industry for continuous manufacturing. For tamper-resistant formulations of e.g. opioids, HME is the most efficient production technique. The focus of this study is thus to evaluate the manufacturability of the HME process for tamper-resistant formulations. Parameters such as the specific mechanical energy (SME), as well as the melt pressure and its standard deviation, are important and will be discussed in this study. In the first step, the existing process data are analyzed by means of multivariate data analysis. Key critical process parameters such as feed rate, screw speed, and the concentration of the API in the polymers are identified, and critical quality parameters of the tablet are defined. In the second step, a relationship between the critical material, product and process quality attributes are established by means of Design of Experiments (DoEs). The resulting SME and the temperature at the die are essential data points needed to indirectly qualify the degradation of the API, which should be minimal. NIR-spectroscopy is used to monitor the material during the extrusion process. In contrast to most applications in which the probe is directly integrated into the die, the optical sensor is integrated into the cooling line of the strands. This saves costs in the probe design and maintenance and increases the robustness of the chemometric models. Finally, a process measurement system is installed to monitor and control all of the critical attributes in real-time by means of first principles, DoE models, soft sensor models, and spectroscopic information. Overall, the process is very robust as long as the screw speed is kept low.

  8. Process design and control of a twin screw hot melt extrusion for continuous pharmaceutical tamper-resistant tablet production.

    Science.gov (United States)

    Baronsky-Probst, J; Möltgen, C-V; Kessler, W; Kessler, R W

    2016-05-25

    Hot melt extrusion (HME) is a well-known process within the plastic and food industries that has been utilized for the past several decades and is increasingly accepted by the pharmaceutical industry for continuous manufacturing. For tamper-resistant formulations of e.g. opioids, HME is the most efficient production technique. The focus of this study is thus to evaluate the manufacturability of the HME process for tamper-resistant formulations. Parameters such as the specific mechanical energy (SME), as well as the melt pressure and its standard deviation, are important and will be discussed in this study. In the first step, the existing process data are analyzed by means of multivariate data analysis. Key critical process parameters such as feed rate, screw speed, and the concentration of the API in the polymers are identified, and critical quality parameters of the tablet are defined. In the second step, a relationship between the critical material, product and process quality attributes are established by means of Design of Experiments (DoEs). The resulting SME and the temperature at the die are essential data points needed to indirectly qualify the degradation of the API, which should be minimal. NIR-spectroscopy is used to monitor the material during the extrusion process. In contrast to most applications in which the probe is directly integrated into the die, the optical sensor is integrated into the cooling line of the strands. This saves costs in the probe design and maintenance and increases the robustness of the chemometric models. Finally, a process measurement system is installed to monitor and control all of the critical attributes in real-time by means of first principles, DoE models, soft sensor models, and spectroscopic information. Overall, the process is very robust as long as the screw speed is kept low. PMID:26386253

  9. The reactive extrusion of thermoplastic polyurethane

    NARCIS (Netherlands)

    Verhoeven, Vincent Wilhelmus Andreas

    2006-01-01

    The objective of this thesis was to increase the understanding of the reactive extrusion of thermoplastic polyurethane. Overall, several issues were identified: • Using a relative simple extrusion model, the reactive extrusion process can be described. This model can be used to further investigate a

  10. Effect of Nano-clay on Rheological and Extrusion Foaming Process of a Block-Copolymerized Polypropylene

    Directory of Open Access Journals (Sweden)

    Wang Mingyi

    2016-01-01

    Full Text Available The effects of nano-clay and the corresponding coupling agent maleic anhydride grafted polypropylene (PP-g-MAH on thermal properties, rheological properties and extrusion foaming process of a block-copolymerized polypropylene (B-PP were studied. Supercritical CO2 (SC CO2 was used as the foaming agent with a concentration of 5wt%. Each step of foamed B-PP/ PP-g-MAH/ nano-clay composites processing is addressed, including mixing of the composites, manufacture of the composites, foaming process of the composites and characterization of the cell structure. The results showed that incorporation of nano-clay and PP-g-MAH caused reduced melt strength and complex viscosity of B-PP. However, the heterogeneous nucleation induced by nano-clay and PP-g-MAH improved the maximum foaming expansion ratio and cell-population density of B-PP foam.

  11. Processing of Copper by Hydrostatic Extrusion – Studies of Microstructure and Properties

    Directory of Open Access Journals (Sweden)

    Leszczyńska-Madej B.

    2016-09-01

    Full Text Available The present study attempts to apply HE to 99.99% pure copper. The microstructure of the samples was investigated by both light microscopy and scanning transmission electron microscopy (STEM. Additionally, the microhardness was measured, the tensile test was made, and statistical analysis of the grains and subgrains was performed. Based on Kikuchi diffraction patterns, misorientation was determined. The obtained results show that microstructure of copper deformed by hydrostatic extrusion (HE is rather inhomogeneous. The regions strongly deformed with high dislocation density exist near cells and grains/subgrains free of dislocations. The measurements of the grain size have revealed that the sample with an initial in annealed-state grain size of about 250 μm had this grain size reduced to below 0.35μm when it was deformed by HE to the strain ε=2.91. The microhardness and UTS are stable within the whole investigated range of deformation.

  12. Resource-saving technology for manufacturing billets for piston’s rings

    Directory of Open Access Journals (Sweden)

    A. N. Krutilin

    2010-10-01

    Full Text Available Piston’s rings are one of the most critical parts of heavy-duty engines for wear-work in conditions of prolonged exposure of alternating loads and high temperatures. Currently in the world production of billets for piston’s rings is dominated by the two methods of casting: production of individual and oiling billets of gray and ductile cast iron in green-sand mold and shell mold and centrifugal casting method (intended primarily for oiling billets of ductile iron; the technology for individual production billets for piston’s rings with a diameter up to 250 mm, from 250 to 450 mm with individual and oiling ways, over 450 mm - preference of oiling billet. The best parameters of physical-mechanical and operational characteristics piston’s rings are in the case of manufacture of billets to the maximum extent approaching the configuration to the finished product. The rings made of shaped billets are characterized by uniform distribution of properties from the perimeter, provide a given diagram of pressures and full fit to the cylinder. Because of deficiencies of traditional methods of casting, continuous quality requirements for billets, the need for economy of material, fuel and energy resources, are finding new progressive technological processes of production of high-quality billets for piston’s rings. One of the most promising for piston rings billet is a method of casting consists of immersing the sand molds into the melt. It is interesting idea, expressed by A. Sutherland and subsequently patented in several countries in the way of casting method, called "immersion pouring technology" (ICT-Immersion Casting Technique [1]. Experiments, conducted in the laboratory of the Belarusian National Technical University, have identified significant shortcomings of immersion method of casting. When forms are immersing, have an intensive gassing in molten metal, and freezing of the metal on the out surface of the form. But despite some

  13. Precision analysis in billet preparation for micro bulk metal forming

    DEFF Research Database (Denmark)

    Mahshid, Rasoul; Hansen, Hans N.

    2015-01-01

    press. When using a vertical mechanical press, the material is fed as billets into the forming zone. Therefore, a large number of highly uniform billets are required to run mass production in such a setup. Shearing technique was used for manufacturing the billets. The efficiency of the shearing tool is......The purpose of this research is to fabricate billets for an automated transfer press for micro forming. High performance transfer presses are wellknown in conventional metal forming and distinguished from their automation and mass production. The press used in this research is a vertical mechanical...

  14. Twin screw extrusion of kodo millet-chickpea blend: process parameter optimization, physico-chemical and functional properties.

    Science.gov (United States)

    Geetha, R; Mishra, H N; Srivastav, P P

    2014-11-01

    Kodo millet-chickpea flour blend (70:30) was explored for development of directly expanded snack by twin-screw extrusion. Effect of process parameters like temperature (80-150 °C), screw speed (250-300 rpm) and feeder speed (15-30 rpm) on physical properties (expansion ratio, bulk density, hardness, crispiness) of extrudates were investigated and optimized using response surface methodology. Desirable crispy extrudates were obtained at higher screw speed 293 rpm, lower feeder speed 19 rpm, and medium to high temperature of 123 °C. Effect of extreme and intermediate process conditions on functional, proximate quality and colour of the extrudates were also evaluated.

  15. A New Method for Controlling Billet Temperature During Isothermal Die Forging of a Complex Superalloy Casing

    Science.gov (United States)

    Lin, Y. C.; Wu, Xian-Yang

    2015-09-01

    Isothermal die forging is one of near net-shape metal-forming technologies. Strict control of billet temperature during isothermal die forging is a guarantee for the excellent properties of final product. In this study, a new method is proposed to accurately control the billet temperature of complex superalloy casing, based on the finite element simulation and response surface methodology (RSM). The proposed method is accomplished by the following two steps. Firstly, the thermal compensation process is designed and optimized to overcome the inevitable heat loss of dies during hot forging. i.e., the layout and opening time of heaters assembled on die sleeves are optimized. Then, the effects of forging speed (the pressing velocity of hydraulic machine) and its changing time on the maximum billet temperature are discussed. Furthermore, the optimized forging speed and its changing time are obtained by RSM. Comparisons between the optimized and conventional die forging processes indicate that the proposed method can effectively control the billet temperature within the optimal forming temperature range. So, the optimized die forging processes can guarantee the high volume fraction of dynamic recrystallization, and restrict the rapid growth of grains in the forged superalloy casing.

  16. Continuous extrusion and rolling forming technology of copper strip manufacture

    OpenAIRE

    Yun Xinbing; Zhou Mo; Tian Tian; Zhao Ying

    2015-01-01

    Continuous extrusion and rolling technology was proposed as a new strip production technology. It finished hot rolling process using the waste heat of the continuous extrusion forming. The continuous extrusion and rolling forming process was simulated by DEFORM-3DT software. The influence of extrusion wheel velocity and strip size on the continuous extrusion and rolling forming process was analyzed. The experiment was carried out according to optimized results of numerical simulation, the mic...

  17. Hot Extrusion Process and Die Design for the Sleeve%套筒热挤压工艺与模具设计

    Institute of Scientific and Technical Information of China (English)

    田福祥

    2011-01-01

    A practical hot extrusion process and die structure was presented. The operational principle and the design of teme die and cavity die were discussed. Different sizes of inverted extrusion cupulate extrusions were manufactured by replacing the teme die an%给出了套筒零件实用的热挤压工艺和模具结构,论述了模具的工作过程及凹模与凸模设计。该模具通过更换凸、凹模,便可生产不同规格的反挤压杯形挤压件,提高了模具利用率,降低了生产成本。

  18. Numerical Simulation Study of Ni-based Pipe in Hot Extrusion for Glass Iubrication Mechanism%镍基管材热挤压中玻璃润滑机理的数值模拟研究

    Institute of Scientific and Technical Information of China (English)

    孙海伟; 范永革; 易勇

    2011-01-01

    模拟摩擦效应对镍基合金管材热挤压的不良影响,着重从挤压力方面讨论了挤压过程的可行性.研究表明:钢坯两侧润滑系数f在0.02~0.03,玻璃垫处在0 01附近,金属匀速流动,径向应力应变分布均匀;当f>0.05时,会造成挤压曲线震荡,不利于热挤压的进行.%The bad influence of friction on hot extrusion of Ni-based alloy pipe was simulated. The feasibility of extrusion process was seriously discussed from extrusion pressure aspects. The results show that when the lubrication coefficient/ is between 0.02 and 0.03 at billet's both sides and is near 0.01 at glass pad, the metal flows uniformly and the radial stress and strain distribute uniformly; when the / is bigger than 0.05, the extrusion curve shocks, and it is not conducive to carry on hot extrusion.

  19. Microstructure and property of a functionally graded aluminum silicon alloy fabricated by semi-solid backward extrusion process

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Kai [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Yu, Hao, E-mail: yhzhmr@126.com [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Liu, Jun-you [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Li, Yan-xia [Department of Materials, North China Institute of Aerospace Engineering, Langfang 065000 (China); Liu, Jian; Zhang, Jia-liang [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-01-29

    In this paper, the microstructure and mechanical property of a graded aluminum silicon alloy were investigated and a new preparation method for the graded material was proposed. The cup-shaped sample was fabricated by the backward extrusion process during the semi-solid state of A390 cast alloy. Characteristics and distribution of the primary particles were assessed by the optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrum (EDS) and image analyzer software. The results showed that the content of primary Si gradually decreased from the bottom region to the upper region. The hardness and wear rate of the samples were measured to evaluate the variation in the mechanical properties corresponding to the variation in microstructure. The hardness values and wear resistance along the axis of the cup-shaped sample gradually increased from the upper region to the bottom region and from the inner region to the outer layer, respectively. The maximum average hardness value is 138.7 HB. The observations of fracture surface were analyzed by scanning electron microscopy to understand the fracture mechanism. The results also indicated that the ultimate tensile strength (UTS) of the graded material after T6 treatment are 275 MPa, increases 32.3% compared to the original backward extrusion alloy. Optical microscopy and electron probe micro-analyzer were used to study the distribution of elements and the microstructure of different intermetallic phases formed. Electron microprobe analysis (EMPA) results showed that the content of the prominent elements (Cu, Fe, Mg) in the upper region was higher than for the bottom part of the cup-shaped specimens.

  20. Mechanical Behavior and Microstructural Analysis of Extruded AZ31B Magnesium Alloy Processed by Backward Extrusion

    Science.gov (United States)

    Zhou, Ping; Beeh, Elmar; Friedrich, Horst E.; Grünheid, Thomas

    2016-07-01

    This study investigates the mechanical behavior of an extruded AZ31B magnesium alloy profile at various strain rates from 0.001 to 375/s. The electron backscatter diffraction analysis revealed that the profile has \\{ { 0 0 0 1} \\}extrusion direction (ED), the profile shows the highest yield strength (YS) but the lowest total elongation at fracture (TE) due to a hard activation of non-basal slip and \\{ { 1 0overline{1} 1} \\}< { 1 0overline{1} overline{2} } rangle twinning; in the diagonal direction (DD), it shows the lowest ultimate tensile strength (UTS) but the highest TE due to an easy activation of basal slip; in the transverse direction (TD), it shows the lowest YS due to an easy activation of \\{ {10overline{1} 2} \\}< {10overline{1} overline{1} } rangle twinning. Moreover, the number of twins increases with the increasing strain rate. This indicates that deformation twinning becomes prevalent to accommodate high-rate deformation. Due to the different deformation mechanisms, the profile exhibits an orientation-dependent effect of strain rate on the mechanical properties. A positive effect of strain rate on the YS and UTS was found in the ED, while the effect of strain rate on the YS is negligible in the DD and TD. The TE in the ED, DD, and TD decreases in general as the strain rate increases. Fractographic analysis under a scanning electron microscope revealed that the fracture is a mixed mode of ductile and brittle fracture, and the magnesium oxide inclusions could be the origins of the fracture.

  1. The processing of ultrafine-grained Mg tubes for biodegradable stents.

    Science.gov (United States)

    Ge, Qiang; Dellasega, David; Demir, Ali Gökhan; Vedani, Maurizio

    2013-11-01

    An investigation was carried out on equal-channel angular pressing (ECAP) and extrusion processing of a ZM21 Mg alloy to obtain an improved candidate material for the manufacturing of biodegradable Mg stents. Ultrafine-grain size billets of the ZM21 alloy were obtained by two-stage ECAP aimed at achieving an initial refining of the structure at 200°C and then reaching the submicrometer grain size range by lowering the processing temperature down to 150°C. The investigation revealed a significant improvement in the properties of the ECAP-treated samples compared with the starting coarse-grained ZM21 alloy. The 0.2% yield strength rose from 180 to 340 MPa after 150°C ECAP processing, while maintaining a fairly high tensile ductility. The ultrafine ZM21 alloy billets were then used for the extrusion of stent precursors having the form of small-size tubes. The grain size after extrusion remained in the submicrometer range while the hardness was revealed to be significantly higher than that of the coarse-grained ZM21 Mg alloy. It was demonstrated that processing of biodegradable Mg stent having an ultrafine-grained microstructure by ECAP and low-temperature extrusion is feasible and that the obtained products feature promising properties. PMID:23333440

  2. Etching Behavior of Aluminum Alloy Extrusions

    Science.gov (United States)

    Zhu, Hanliang

    2014-11-01

    The etching treatment is an important process step in influencing the surface quality of anodized aluminum alloy extrusions. The aim of etching is to produce a homogeneously matte surface. However, in the etching process, further surface imperfections can be generated on the extrusion surface due to uneven materials loss from different microstructural components. These surface imperfections formed prior to anodizing can significantly influence the surface quality of the final anodized extrusion products. In this article, various factors that influence the materials loss during alkaline etching of aluminum alloy extrusions are investigated. The influencing variables considered include etching process parameters, Fe-rich particles, Mg-Si precipitates, and extrusion profiles. This study provides a basis for improving the surface quality in industrial extrusion products by optimizing various process parameters.

  3. An integrated numerical model for the prediction of Gaussian and billet shapes

    DEFF Research Database (Denmark)

    Hattel, Jesper; Pryds, Nini; Pedersen, Trine Bjerre

    2004-01-01

    Separate models for the atomisation and the deposition stages were recently integrated by the authors to form a unified model describing the entire spray-forming process. In the present paper, the focus is on describing the shape of the deposited material during the spray-forming process, obtained...... and the shading effect for Gaussian and billet shape, respectively. From the obtained results, the effect of these parameters on the final shape is illustrated. (C) 2004 Elsevier B.V. All rights reserved....

  4. Microstructure and mechanical properties of 7075 aluminum alloy nanostructured composites processed by mechanical milling and indirect hot extrusion

    International Nuclear Information System (INIS)

    Nanostructured composites of 7075 aluminum alloy and carbon coated silver nanoparticles were produced by mechanical milling and indirect hot extrusion. The milling products were obtained in a high energy SPEX ball mill, and then were compacted by uniaxial load and pressure-less sintered under argon atmosphere. Finally, the sintered product was hot extruded. Carbon coated silver nanoparticles were well distributed in the matrix of the extruded material. Tensile tests were carried out to corroborate the hypothesis that second phase particles, well dispersed in the matrix, improve the strength of the material. High resolution transmission electron microscopy was employed to locate and make sure that the silver nanoparticles were homogeneously and finely dispersed. Highlights: ► 7075 Al nanostructured composites can be produced by mechanical milling. ► Carbon coated silver nanoparticles are well dispersed into aluminum matrix. ► Ductile Ag–C NP's improve the mechanical properties of the 7075 Al-alloy. ► Ag–C NP's content has an important effect in the particle and crystallite size. ►Ag–C NP's keep their morphology after milling and conformation processes.

  5. Response surface methodology for evaluation and optimization of process parameter and antioxidant capacity of rice flour modified by enzymatic extrusion.

    Science.gov (United States)

    Xu, Enbo; Pan, Xiaowei; Wu, Zhengzong; Long, Jie; Li, Jingpeng; Xu, Xueming; Jin, Zhengyu; Jiao, Aiquan

    2016-12-01

    For the purpose of investigating the effect of enzyme concentration (EC), barrel temperature (BT), moisture content (MC), and screw speed (SS) on processing parameters (product temperature, die pressure and special mechanical energy (SME)) and product responses (extent of gelatinization (GE), retention rate of total phenolic content (TPC-RR)), rice flour extruded with thermostable α-amylase was analyzed by response surface methodology. Stepwise regression models were computed to generate response surface and contour plots, revealing that both TPC-RR and GE increased as increasing MC while expressed different sensitivities to BT during enzymatic extrusion. Phenolics preservation was benefited from low SME. According to multiple-factor optimization, the conditions required to obtain the target SME (10kJ/kg), GE (100%) and TPC-RR (85%) were: EC=1.37‰, BT=93.01°C, MC=44.30%, and SS=171.66rpm, with the actual values (9.49kJ/kg, 99.96% and 87.10%, respectively) showing a good fit to the predicted values. PMID:27374518

  6. Microstructure and mechanical properties of 7075 aluminum alloy nanostructured composites processed by mechanical milling and indirect hot extrusion

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Campos, R., E-mail: ruben.flores@itesm.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No. 120, CP 31109, Chihuahua, Chih., Mexico (Mexico); Tecnologico de Monterrey Campus Saltillo, Departamento de Ingenieria, Prol. Juan de la Barrera No. 1241 Ote., Col. Cumbres, CP 25270, Saltillo, Coah., Mexico (Mexico); Estrada-Guel, I., E-mail: ivanovich.estrada@cimav.edu.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No. 120, CP 31109, Chihuahua, Chih., Mexico (Mexico); Miki-Yoshida, M., E-mail: mario.miki@cimav.edu.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No. 120, CP 31109, Chihuahua, Chih., Mexico (Mexico); Martinez-Sanchez, R., E-mail: roberto.martinez@cimav.edu.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No. 120, CP 31109, Chihuahua, Chih., Mexico (Mexico); Herrera-Ramirez, J.M., E-mail: martin.herrera@cimav.edu.mx [Centro de Investigacion en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes No. 120, CP 31109, Chihuahua, Chih., Mexico (Mexico)

    2012-01-15

    Nanostructured composites of 7075 aluminum alloy and carbon coated silver nanoparticles were produced by mechanical milling and indirect hot extrusion. The milling products were obtained in a high energy SPEX ball mill, and then were compacted by uniaxial load and pressure-less sintered under argon atmosphere. Finally, the sintered product was hot extruded. Carbon coated silver nanoparticles were well distributed in the matrix of the extruded material. Tensile tests were carried out to corroborate the hypothesis that second phase particles, well dispersed in the matrix, improve the strength of the material. High resolution transmission electron microscopy was employed to locate and make sure that the silver nanoparticles were homogeneously and finely dispersed. Highlights: Black-Right-Pointing-Pointer 7075 Al nanostructured composites can be produced by mechanical milling. Black-Right-Pointing-Pointer Carbon coated silver nanoparticles are well dispersed into aluminum matrix. Black-Right-Pointing-Pointer Ductile Ag-C NP's improve the mechanical properties of the 7075 Al-alloy. Black-Right-Pointing-Pointer Ag-C NP's content has an important effect in the particle and crystallite size. Black-Right-Pointing-Pointer Ag-C NP's keep their morphology after milling and conformation processes.

  7. Blasting extrusion processing: the increase of soluble dietary fiber content and extraction of soluble-fiber polysaccharides from wheat bran.

    Science.gov (United States)

    Yan, Xiaoguang; Ye, Ran; Chen, Ye

    2015-08-01

    In this study, soluble dietary fiber (SDF) content of wheat bran was significantly increased from 9.82 ± 0.16 (w/w, %) to 16.72 ± 0.28 (w/w, %) by a novel blasting extrusion processing with enhanced water retention capacity and the swelling capacity. In addition, a water-soluble polysaccharide (WBP) was isolated and extracted from extruded SDF. WBP was successfully purified from SDF by column chromatography systems with the average molecular weight (Mw) of 4.7 × 10(4)Da, containing arabinose, xylose, glucose, and galactose. With the molar ratio of 0.76:0.99:1.00:0.12. Our results suggest that WBP owned 1 → 2, 1 → 3, 1 → 2, 6 and 1 → 4, 1 → 4, 6 glycosidic bonds in the absence of 1 →, 1 → 6 glycosidic bonds. In vitro antioxidant assays (DPPH, ABTS+ radical scavenging capacities, and ferric ion reducing capacity) demonstrated that WBP possesses good antioxidant capacity, and it could be potentially used as a natural antioxidant for use in functional food, cosmetic and pharmaceutical industries. PMID:25766807

  8. Optimization of extrusion process for production of nutritious pellets Otimização do processo de extrusão para a produção de pellets nutricional

    Directory of Open Access Journals (Sweden)

    Ernesto Aguilar-Palazuelos

    2012-03-01

    Full Text Available A blend of 50% Potato Starch (PS, 35% Quality Protein Maize (QPM, and 15% Soybean Meal (SM were used in the preparation of expanded pellets utilizing a laboratory extruder with a 1.5 × 20.0 × 100.0 mm die-nozzle. The independent variables analyzed were Barrel Temperature (BT (75-140 °C and Feed Moisture (FM (16-30%. The effect of extrusion variables was investigated in terms of Expansion Index (EI, apparent density (ApD, Penetration Force (PF and Specific Mechanical Energy (SME, viscosity profiles, DSC, crystallinity by X-ray diffraction, and Scanning Electronic Microscopy (SEM. The PF decreased from 30 to 4 kgf with the increase of both independent variables (BT and FM. SME was affected only by FM, and decreased with the increase in this variable. The optimal region showed that the maximum EI was found for BT in the range of 123-140 °C and 27-31% for FM, respectively. The extruded pellets obtained from the optimal processing region were probably not completely degraded, as shown in the structural characterization. Acceptable expanded pellets could be produced using a blend of PS, QPM, and SM by extrusion cooking.Neste trabalho foram elaborados pellets expandidos a partir da mistura de 50% de Amido de Batata (AB, 35% de Milho de Qualidade Protéica (MQP e 15% de Farelo de Soja (FS, utilizando extrusor de laboratório com matriz de 1,5 × 20,0 × 100,0 mm. As variáveis independentes analisadas foram: Temperatura de Extrusão (TE (75-140 °C e Umidade da Mistura (UM (16-30%. O efeito das variáveis de extrusão foram estudadas quanto ao Índice de Expansão (IE, a densidade aparente (DA, força de penetração (FP, Energia Mecânica Específica (EME, perfil de viscosidade, DSC, cristalinidade através de difração de raio X e Microscopia Eletrônica de Varredura (MEV. A PF diminuiu de 30 para 4 kgf com o aumento de ambas as variáveis independentes (TE e UM. EME foi afetada somente pela UM, diminuindo com o aumento desta variável. A regi

  9. Analysis of Process Parameters for Optimization of Plastic Extrusion in Pipe Manufacturing

    Directory of Open Access Journals (Sweden)

    Mr. Sandip S. Gadekar

    2015-05-01

    Full Text Available The objective of this paper is to study the defects in the plastic pipe, to optimize the plastic pipe manufacturing process. It is very essential to learn the process parameter and the defect in the plastic pipe manufacturing process to optimize it. For the optimization Taguchi techniques is used in this paper. For the research work Shivraj HY-Tech Drip Irrigation pipe manufacturing, Company was selected. This paper is specifically design for the optimization in the current process. The experiment was analyzed using commercial Minitab16 software, interpretation has made, and optimized factor settings were chosen. After prediction of result the quality loss is calculated and it is compare with before implementation of DOE. The research works has improves the Production, quality and optimizes the process.

  10. Modeling, Prediction, and Control of Heating Temperature for Tube Billet

    Directory of Open Access Journals (Sweden)

    Yachun Mao

    2015-01-01

    Full Text Available Annular furnaces have multivariate, nonlinear, large time lag, and cross coupling characteristics. The prediction and control of the exit temperature of a tube billet are important but difficult. We establish a prediction model for the final temperature of a tube billet through OS-ELM-DRPLS method. We address the complex production characteristics, integrate the advantages of PLS and ELM algorithms in establishing linear and nonlinear models, and consider model update and data lag. Based on the proposed model, we design a prediction control algorithm for tube billet temperature. The algorithm is validated using the practical production data of Baosteel Co., Ltd. Results show that the model achieves the precision required in industrial applications. The temperature of the tube billet can be controlled within the required temperature range through compensation control method.

  11. Physical modelling and numerical simulation of the round-to-square forward extrusion

    DEFF Research Database (Denmark)

    Gouveia, B.P.P.A.; Rodrigues, J.M.C.; Martins, P.A.F.;

    2001-01-01

    In this paper, three-dimensional forward extrusion of a square section from a round billet through a straight converging die is analysed using both physical modelling and numerical simulation (finite element and upper bound analysis). Theoretical fundamentals for each method are reviewed......, and comparisons are made between the numerical predictions and experimental data obtained through the utilisation of physical modelling. Assessment is made in terms of flow pattern and strain distribution for two different cross-sections corresponding to the axial symmetry planes of the three......-dimensional extrusion part. The experimental distribution of strain is determined from the shape change of quadrilateral grids previously printed on the surface of the axial cross-sections of the undeformed billets by means of large deformation square-grid analysis. Good agreement is obtained between physical...

  12. The Extrusion Process as an Alternative for Improving the Biological Potential of Sorghum Bran: Phenolic Compounds and Antiradical and Anti-Inflammatory Capacity

    Science.gov (United States)

    Salazar Lopez, Norma Julieta; Loarca-Piña, Guadalupe; Campos-Vega, Rocío; Gaytán Martínez, Marcela; Morales Sánchez, Eduardo; Esquerra-Brauer, J. Marina; Gonzalez-Aguilar, Gustavo A.

    2016-01-01

    Approximately 80% of sorghum phenolic compounds are linked to arabinoxylans by ester bonds, which are capable of resisting the digestion process in the upper gastrointestinal tract, compromising their bioaccessibility and biological potential. The aim of this study was to evaluate the effect of the extrusion process on the content of phenolic compounds in sorghum bran and its impact on phenolic compounds and antiradical and anti-inflammatory capacity. Results revealed that the extrusion process increased total phenol content in sorghum bran compared to nonextruded sorghum, particularly for extrusion at 180°C with 20% moisture content (2.0222 ± 0.0157 versus 3.0729 ± 0.0187 mg GAE/g +52%), which positively affected antiradical capacity measured by the DPPH and TEAC assays. The percentage of inhibition of nitric oxide (NO) production by RAW cells due to the presence of extruded sorghum bran extract was significantly higher than that of nonextruded sorghum bran extract (90.2 ± 1.9% versus 76.2 ± 1.3%). The results suggest that extruded sorghum bran could be used as a functional ingredient and provide advantages to consumers by reducing diseases related to oxidative stress and inflammation. PMID:27738445

  13. Application of extrusion-cooking for processing of thermoplastic starch (TPS)

    NARCIS (Netherlands)

    Moscicki, Leszek; Mitrus, Marcin; Wojtowicz, Agnieszka; Oniszczuk, Tomasz; Rejak, Andrzej; Janssen, Leon; Mościcki, Leszek

    2012-01-01

    Thermoplastic starch (TPS) as fully biodegradable biopolymer appeared to be one of the most useful and promising materials for packaging purpose. To obtain TPS thermal and mechanical processing should disrupt semi-crystalline starch granules. As the melting temperature of pure starch is substantiall

  14. Influence of extrusion processing on procyanidin composition and total anthocyanin contents of blueberry pomace

    Science.gov (United States)

    Blueberry juice processing by-products are a rich source of procyanidins, which comprise a group of compounds shown to possess numerous health benefits including, protection against coronary heart disease, type II diabetes, and obesity. Most of the procyanidins present in blueberry pomace, however,...

  15. Chemical changes during extrusion cooking. Recent advances.

    Science.gov (United States)

    Camire, M E

    1998-01-01

    Cooking extruders process a variety of foods, feeds, and industrial materials. Greater flexibility in product development with extruders depends upon understanding chemical reactions that occur within the extruder barrel and at the die. Starch gelatinization and protein denautration are the most important reactions during extrusion. Proteins, starches, and non-starch polysaccharides can fragment, creating reactive molecules that may form new linkages not found in nature. Vitamin stability varies with vitamin structure, extrusion conditions, and food matrix composition. Little is known about the effects of extrusion parameters on phytochemical bioavailability and stability. Reactive extrusion to create new flavor, antioxidant and color compounds will be an area of interest in the future.

  16. EFFECTS OF LINEAR ELECTROMAGNETIC STIRRING ON THE SOLIDIFICATION STRUCTURE OF BILLET

    Institute of Scientific and Technical Information of China (English)

    H.L. Zhang; E.G. Wang; G.L. Jia; J.C. He

    2001-01-01

    The effects of linear electromagnetic stirring (EMS) on the solidification steacture of billet were investigated by experiments, and the electromagnetic fields and flow fields during the stirring process were analyzed by numerical simulation. The results show that the billet of almost 100% equiaxed grains can be obtained by applying linear EMS at the maximum intensity of 1414A.Hz1/2, while the maximum electromagnetic force and the maximum velocity in the molten steel are 6386N-m-3 and 0.22m.s-1,respectively. It is presented that the pulsating electromagnetic force perpendicular to the movement of the molten steel, is an important factor of increasing the equiaxed zone ratio in the solidification structure, which further prevents the appearance of white band and internal defects.

  17. Two-Step Solid Lipid Extrusion as a Process to Modify Dissolution Behavior

    OpenAIRE

    Windbergs, Maike; Gueres, Sinan; Strachan, Clare J.; Kleinebudde, Peter

    2010-01-01

    Extrudates based on varying ratios of the triglyceride tripalmitin and the hydrophilic polymer polyethylene glycol as matrix formers were produced as oral dosage forms with controlled release characteristics. The extrudates were processed below the melting points of the excipients and contained the hydrophobic model drug chloramphenicol. The influence of the ratio of the matrix formers on drug dissolution was investigated, with an increase in the water-soluble polymer content increasing the d...

  18. A simple calibration approach based on film-casting for confocal Raman microscopy to support the development of a hot-melt extrusion process.

    Science.gov (United States)

    Netchacovitch, L; Thiry, J; De Bleye, C; Dumont, E; Dispas, A; Hubert, C; Krier, F; Sacré, P-Y; Evrard, B; Hubert, Ph; Ziemons, E

    2016-07-01

    When developing a new formulation, the development, calibration and validation steps of analytical methods based on vibrational spectroscopy are time-consuming. For each new formulation, real samples must be produced and a "reference method" must be used in order to determine the Active Pharmaceutical Ingredient (API) content of each sample. To circumvent this issue, the paper presents a simple approach based on the film-casting technique used as a calibration tool in the framework of hot-melt extrusion process. Confocal Raman microscopic method was successfully validated for the determination of itraconazole content in film-casting samples. Then, hot-melt extrusion was carried out to produce real samples in order to confront the results obtained with confocal Raman microscopy and Ultra High Performance Liquid Chromatography (UHPLC). The agreement between both methods was demonstrated using a comparison study based on the Bland and Altman's plot. PMID:27154691

  19. Lateral extrusion of tailor welded aluminum alloy pipes with a lost core of low temperature melting alloy

    Directory of Open Access Journals (Sweden)

    T. Ohashi

    2009-01-01

    Full Text Available Purpose: In this paper, the authors employ tailor welded aluminum alloy pipes for lateral extrusion process with a lost core to perform a hollow light-weight-part.Design/methodology/approach: The pipe is welded longitudinally by YAG-laser. “The lateral extrusion process with a lost core (LELC” consists of lateral extrusion of pipes with a soluble solid core, called the “lost core”, which serves as a plastic mandrel. The process proceeds as follows. First, the pipe cavity is filled with the liquid low temperature melting material composing the lost core. The liquid is then solidified to form the soluble core of the pipe. The material is compressed longitudinally as a composite billet as well as forging, and extruded in the lateral direction. After the pipe is deformed, the lost core is melted and removed. s. The bulge by the LELC is carried out by extruding the material for the lateral direction, however the simple bulge by hydro-forming is done by internal pressure.Findings: The LELC process can make a hollow product having uneven wall thickness without the deformation concentrating on a thinner part of the material, because the circumferential deformation of the material will be performed by its meridian strain.Practical implications: The authors have developed LELC process in which the lost core consists of low-temperature melting alloys and have tried to apply the process to perform bulge process with a tailor-welded pipe having two different wall thickness.Originality/value: Optimum volume distribution is important for light-weight-parts, and employment of tailor-welded blanks is effective technique in sheet metal forming. Combination of employment of hollow shape and tailor-welded blanks seems to be hopeful.

  20. Twin-screw Extrusion Processing of Distillers Dried Grains With Solubles (DDGS)-based Rainbow Trout (Oncorhynchus mykiss) Feeds

    Science.gov (United States)

    The world’s increasing demand for seafood products has resulted in rising demands for fish meal for fish feed, which must be compensated for by searching for effective alternative protein sources. In this study, twin-screw extrusion trials were conducted to study the production of nutritionally-bala...

  1. MM98.43 Experimental determination of the heat transfer coefficient Under dynamic process conditions in backward can extrusion

    DEFF Research Database (Denmark)

    Henningsen, Poul; Hattel, Jesper Henri; Wanheim, Tarras

    1998-01-01

    The large deformations in backward can extrusion result in a rise of temperature of more than 200 oC. In the experiments, cans in low carbon steel are formed with a lubrication layer of phosphate soap. The temperature is measured by thermocouples in the die insert and the punch. The die insert is...

  2. Development of medical tube fabrication process from RVNRL: optimization and extrusion device at low temperature

    International Nuclear Information System (INIS)

    The natural rubber latex was formulated, irradiation vulcanized and stabilized (GAMATEX) to make rubber goods for medical purpose. When the latex was vulcanized by gamma rays the effectiveness crosslinking of GAMATEX relationship between the concentration ratio of sensitizer system (x1=[n-BA]/[KOH]) and the vulcanization dose (x2), showing high interaction grade. The RVNRL process was optimized for low vulcanization doses and high concentrations of n-BA. The resistance to radiolytic oxidation of rubber obtained from GAMATEX was attained when one antioxidants mixture (45% BANOX S + 55% TNPP) was added. This mixture exhibited synergetic effect. The latex showed pseudoplastic rheological behavior and the yield stress occurrence. The irreversible destabilization rate of latex was direct proportional to [n-BA] and indirect proportional to [KOH]. The post-irradiation effects or reversible destabilization of latex occurred because there is a residual concentration of [n-BA] that it was not reacted. The colloidal stability of GAMATEX improved with irradiation, showing showing the increase of thixotropic behavior and the tendency to Newtonian behavior flow besides the relationship between the viscosity index (k) and the pseudoplastic index (n). This fact allows the higher storage time of GAMATEX. The relative viscosity of latex was relationship between the temperature and the total dry rubber content according to the mathematical model: logηrel = 0,18+1,09rw, where rw is the ratio (BS/100-BS). The radiation vulcanized latex coagulated at -10 deg C into the projected freezing system. (author)

  3. Spray forming: A numerical investigation of the influence of the gas to melt ratio on the billet surface temperature

    DEFF Research Database (Denmark)

    Pryds, Nini; Hattel, Jesper

    2005-01-01

    The relationship between the Gas to Melt Ratio (GMR) and the surface temperature of an evolving billet surface in spray forming is investigated numerically. The basis for the analysis is an integrated approach for modelling the entire spray forming process. This model includes the droplet atomisa...

  4. Extrusion of ECC: Recent Developments and Applications

    DEFF Research Database (Denmark)

    Stang, Henrik; Fredslund-Hansen, Helge; Puclin, Tony;

    2008-01-01

    demands on the rheological properties of cementitious particulate materials, various methods have been suggested to dewater the particle suspension during extrusion, however practical extrusion of thin-walled cementitious large-scale elements has not been possible until the discovery of the “dewatering......Extrusion of particulate pastes and suspensions in general is difficult and the rheological parameters play a central role in the process when using conventional extruders. More important – the rheological properties of the paste or suspension are subjected to conflicting demands in an extrusion...... process. Extrusion of cementitious (fiber reinforced) materials has proven particularly difficult due to the high inter-particle friction combined with the disastrous effect of static zones in the flow pattern, and to the ease of phase migration or separation. In order to deal with these conflicting...

  5. FEM study of extrusion complexity and dead metal zone

    OpenAIRE

    S.Z. Qamar

    2009-01-01

    Purpose: Quality of the extruded product and efficiency of the manufacturing process can be seriously affected by inconsistent metal flow through the extrusion die. Metal flow problems can also significantly reduce die life. Various researchers have investigated the effect of profile complexity on extrusion pressure, product quality, die life, etc. However, the relationship between shape complexity and metal flow through the extrusion die has not been studied in detail. Cold extrusion experim...

  6. Development of rheological characterization and twin-screw extrusion/spiral winding processing methods for functionally-graded tissue engineering scaffolds and characterization of cell/biomaterial interactions

    Science.gov (United States)

    Ozkan, Seher

    Tissue engineering involves the fabrication of biodegradable scaffolds, on which various types of cells are grown, to provide tissue constructs for tissue repair/regeneration. Native tissues have complex structures, with functions and properties changing spatially and temporally, and require special tailoring of tissue engineering scaffolds to allow mimicking of their complex elegance. The understanding of the rheological behavior of the biodegradable polymer and the thermo-mechanical history that the polymer experiences during processing is critical in fabricating scaffolds with appropriate microstructural distributions. This study has first focused on the rheological material functions of various gel-like fluids including biofluids and hydrogels, which can emulate the viscoelastic behavior of biofluids. Viscoplasticity and wall slip were recognized as key attributes of such systems. Furthermore, a new technology base involving twin-screw extrusion/spiral winding (TSESW) process was developed for the shaping of functionally-graded scaffolds. This novel scaffold fabrication technology was applied to the development of polycaprolactone (PCL) scaffolds, incorporated with tricalcium phosphate nanoparticles and various porogens in graded fashion. The protein encapsulation and controlled release capabilities of the TSESW process was also demonstrated by dispersing bovine serum albumin (BSA) protein into the PCL matrix. Effects of processing conditions and porosity distributions on compressive properties, surface topography, encapsulation efficiency, release profiles and the secondary structure of BSA were investigated. The PCL scaffolds were determined to be biocompatible, with the proliferation rates of human fetal osteoblast cells (hFOB) increasing with increasing porosity and decreasing concentration of TCP. BSA proteins were determined to be denatured to a greater extent with melt extrusion in the 80-100°C range (in comparison to wet extrusion using organic

  7. Method of Determining the Filtration Properties of oil-Bearing Crops in the Process of Their Pressing by the Example of Rape-oil Extrusion

    Science.gov (United States)

    Slavnov, E. V.; Petrov, I. A.

    2014-07-01

    A method of determining the change in the fi ltration properties of oil-bearing crops in the process of their pressing by repeated dynamic loading is proposed. The use of this method is demonstrated by the example of rape-oil extrusion. It was established that the change in the mass concentration of the oil in a rape mix from 0.45 to 0.23 leads to a decrease in the permeability of the mix by 101.5-102 times depending on the pressure applied to it. It is shown that the dependence of the permeability of this mix on the pressure applied to it is nonmonotone in character.

  8. Single-ring hollow core optical fibers made by glass billet extrusion for Raman sensing.

    Science.gov (United States)

    Tsiminis, G; Rowland, K J; Schartner, E P; Spooner, N A; Monro, T M; Ebendorff-Heidepriem, H

    2016-03-21

    We report the fabrication of the first extruded hollow core optical fiber with a single ring of cladding holes, and its use in a chemical sensing application. These single suspended ring structures show antiresonance reflection optical waveguiding (ARROW) features in the visible part of the spectrum. The impact of preform pressurization on the geometry of these fibers is determined by the size of the different hole types in the preform. The fibers are used to perform Raman sensing of methanol, demonstrating their potential for future fiber sensing applications. PMID:27136787

  9. Manufacturing and mechanical property test of the large-scale oxide dispersion strengthened martensitic mother tube by hot isostatic pressing and hot extrusion process

    International Nuclear Information System (INIS)

    Mass production capability of Oxide Dispersion Strengthened (ODS) ferritic steel cladding (9Cr) is evaluated in the Phase II of the Feasibility Studies on Commercialized Fast Reactor Cycle System. The cost for manufacturing mother tube is a dominant factor in the total cost for manufacturing ODS ferritic cladding. In this study, the large-scale 9Cr-ODS martensitic mother tube was produced by overseas supplier with mass production equipments for commercialized ODS steels. The process of manufacturing the ODS mother tube consists of raw material powder production, mechanical alloying by high energy ball mill, hot isostatic pressing(HIP), and hot extrusion. Following results were obtained in this study. (1) Micro structure of the ODS steels is equivalent to that of domestic products, and fine oxides are uniformly distributed. The mechanical alloying by large capacity (1 ton) ball mill can be satisfactorily carried out. (2) A large scale mother tube (65 mm OD x 48 mm ID x 10,000 mm L), which can produce about 60 pieces of 3 m length ODS ferritic claddings by four times cold rolling, have been successfully manufactured through HIP and Hot Extrusion process. (3) Rough surface of the mother tubes produced in this study can be improved by selecting the reasonable hot extrusion condition. (4) Hardness and tensile strength of the manufactured ODS steels are lower than domestic products with same chemical composition. This is owing to the high aluminum content in the product, and those properties could be improved by decreasing the aluminum content in the raw material powder. (author)

  10. Application of quality by design (QbD) to formulation and processing of naproxen pellets by extrusion-spheronization.

    Science.gov (United States)

    Wang, Junlin; Kan, Shuling; Chen, Tong; Liu, Jianping

    2015-03-01

    The aim of this research was to apply quality by design (QbD) to the development of naproxen loaded core pellets which can be used as the potential core for colon-specific pellets. In the early stages of this study, prior knowledge and preliminary studies were systematically incorporated into the risk assessment using failure mode and effect analysis (FMEA) and fishbone diagram. Then Plackett-Burman design was used to screen eight potential high risk factors (spheronization speed, spheronization time, extrusion speed, drying method, CCMC-Na concentration, lactose concentration, water concentration and Tween 80 concentration) obtained from the above risk assessment. It was discovered that out of the eight potential high risk factors only three factors (spheronization speed, extrusion speed and CCMC-Na concentration) had significant effects on the quality of the pellets. This allowed the use of Box-Behnken design (BBD) to fully elucidate the relationship between the variables and critical quality attribute (CQA). Finally, the final control space was established within which the quality of the pellets can meet the requirement of colon-specific drug delivery system. This study demonstrated that naproxen loaded core pellets were successfully designed using QbD principle.

  11. Effects of selected process parameters in extrusion of yam flour (Dioscorea rotundata) on physicochemical properties of the extrudates.

    Science.gov (United States)

    Sebio, L; Chang, Y K

    2000-04-01

    Raw yam (Dioscorea rotundata) flour was cooked and extruded in a Brabender single-screw laboratory scale extruder. Response surface methodology using an incomplete factorial design was applied with various combinations of barrel temperature [100, 125, 150 degrees C], feed moisture content [18, 22, 26%] and screw speed [100, 150, 200 rpm]. Initial viscosity at 30 degrees C, water solubility index, expansion and hardness were determined. The highest values of initial viscosity were at the highest barrel temperatures and the highest moisture contents. At high feed moisture content and high barrel temperatures the yam extrudate flour showed the greatest values of water solubility index. The physical properties of the extruded product showed that at high temperature the lower the moisture content the greater the expansion index. Hardness was influenced directly by moisture content and inversely by extrusion temperature. The extrusion of yam flour led to the production of snacks and pre-gelatinized flours of diverse properties. Also extruded yam flour can be successfully used in the preparation of 'futu' (pre-cooked compact dough), a yam-based food, popular in Western Africa.

  12. Application of quality by design (QbD) to formulation and processing of naproxen pellets by extrusion-spheronization.

    Science.gov (United States)

    Wang, Junlin; Kan, Shuling; Chen, Tong; Liu, Jianping

    2015-03-01

    The aim of this research was to apply quality by design (QbD) to the development of naproxen loaded core pellets which can be used as the potential core for colon-specific pellets. In the early stages of this study, prior knowledge and preliminary studies were systematically incorporated into the risk assessment using failure mode and effect analysis (FMEA) and fishbone diagram. Then Plackett-Burman design was used to screen eight potential high risk factors (spheronization speed, spheronization time, extrusion speed, drying method, CCMC-Na concentration, lactose concentration, water concentration and Tween 80 concentration) obtained from the above risk assessment. It was discovered that out of the eight potential high risk factors only three factors (spheronization speed, extrusion speed and CCMC-Na concentration) had significant effects on the quality of the pellets. This allowed the use of Box-Behnken design (BBD) to fully elucidate the relationship between the variables and critical quality attribute (CQA). Finally, the final control space was established within which the quality of the pellets can meet the requirement of colon-specific drug delivery system. This study demonstrated that naproxen loaded core pellets were successfully designed using QbD principle. PMID:25069591

  13. Numerical Simulation of Re -Extrusion Process for Self -Lubricating Spherical Plain Bearings%自润滑关节轴承二次挤压装配的有限元仿真分析

    Institute of Scientific and Technical Information of China (English)

    张瑞芬; 吴连平; 杨晓翔

    2015-01-01

    利用 Abaqus 软件对大型自润滑关节轴承的成形过程进行了数值模拟。通过分析挤压过程中轴承的等效应力分布、等效塑性应变分布、挤压力变化曲线及衬垫受到的接触应力分布曲线等,研究自润滑关节轴承的装配成形机理。结果表明:相对第2次挤压成形,第1次挤压成形过程中挤压力变化相对平稳,等效应力和等效塑性应变也相对较小;第1次挤压完成后,衬垫腰部受到的接触应力最大,第2次挤压完成后,衬垫两端受到的接触应力较大。%The forming process for large self -lubricating spherical plain bearings is numerically simulated by using software Abaqus.The assembly forming mechanism for self -lubricating spherical plain bearings is studied by analyzing equivalent stress distribution,equivalent plastic strain distribution,variable curve for extrusion force and contact pres-sure distribution curves of liner for bearings during extrusion process.The result show that compared to second extrusion forming,the change of extrusion force is more stable and the equivalent stress and plastic strain is smaller during first extrusion process.After first extrusion,the waist of liner has the biggest contact pressure while both ends of liner have bigger contact pressure after second extrusion.

  14. Co-extrusion of piezoelectric ceramic fibres

    OpenAIRE

    Ismael Michen, Marina

    2011-01-01

    The present work successfully developed a methodology for fabricating lead zirconate titanate [PZT] thin solid- and hollow-fibres by the thermoplastic co-extrusion process. The whole process chain, that includes: a) compounding, involving the mixing of ceramic powder with a thermoplastic binder, b) rheological characterizations, c) preform composite fabrication followed by co-extrusion, d) debinding and, finally, e) sintering of the body to near full density, is systematical...

  15. The extrusion of AZ-series magnesium alloys - extending the processing limits by hydrostatic extrusion; Erweiterung der Prozessgrenzen beim Strangpressen von Magnesiumknetlegierungen der AZ-Reihe durch das hydrostatische Strangpressverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Swiostek, J. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung

    2008-12-04

    The present study is concerned with the analysis of the influence of hydrostatic extrusion on the microstructural development and mechanical properties of extruded profiles of the AZ-series magnesium alloys. This work also deals with the correlation between the microstructure and resulting mechanical properties for the case extruded profiles. (orig.)

  16. Extrusion of ECC-Material

    DEFF Research Database (Denmark)

    Stang, Henrik; Li, Victor C.

    1999-01-01

    An extrusion process especially designed for extrusion of pipes made from fiber reinforced cementitious materials has been developed at Department of Structural Engineering and Materials at the Technical University of DenmarkEngineered Cementitious Composite (ECC) materials have been developed in...... recent years at Department of Civil and Envirionmetal Engineering, University of Michigan. These materials have been developed with the special aim of producing high performance , strain hardening materials with low volume concentrations of short fibers in a cementitious material.ECC material spcimens...... have until now been produced by traditional casting processes. In the present paper results from a recent collaborative reserach project are documented - demonstrating that ECC materials can be extruded in the process referred to above....

  17. Whole process modeling of joining of flareless AA 6061-T4 tube by extrusion-bulging forming using a polyurethane elastomer medium

    Science.gov (United States)

    Yang, J. C.; Li, H.; Yang, H.; Li, G. J.

    2016-08-01

    The tube joining by plastic deformation proves to be a more efficient and environmentally friendly way to achieve the tube-tube joining compared with other traditional types, such as metallurgical joining and mechanical joining. In this study, to reveal the effects of the processing parameters on the filling quality and residual contact stress, an axisymmetric finite element (FE) model of the whole joining process, including extrusion-bulging forming and unloading, was established and validated. The aluminum alloy (AA) 6061-T4 tubes, the stainless steel (ST) 15-5PH sleeve and polyurethane (PU) elastomer medium were characterized and modeled. And the implicit algorithm was adopted by comparing the prediction results between explicit and implicit FE models. The characteristics of stress distribution and plastic strain for the tube, PU elastomer and sleeve were discussed.

  18. The Finite Element Simulation of Isothermal Extrusion Process of TC2 Alloy Pipe%TC2钛合金管材等温挤压过程的有限元模拟

    Institute of Scientific and Technical Information of China (English)

    马静; 曾卫东; 袁本福; 周建华

    2012-01-01

    The isothermal-extrusion process of TC2 alloy pipe was simulated, and the field variables of the pipe at different extrusion stages were analyzed simultaneously by using DEFORM-3D FEM. Then the friction coefficient was determined by fitting the calculated load to the actual one. and the effect of friction coefficient and half cone angle of die on the extrusion load was also discussed.%采用DEFORM-3D有限元法模拟了TC2合金管材的等温挤压成形过程,并对挤压过程中不同阶段的各种场量进行了分析,通过与实际生产对比确定了挤压摩擦因数,同时分析了不同的摩擦因数和凹模半锥角对挤压载荷的影响.

  19. Processing of Mo-Si-B intermetallics by extrusion and oxidation properties of the extruded Tl-MoSi{sub 2}-MoB System

    Energy Technology Data Exchange (ETDEWEB)

    Summers, Eric

    1999-11-08

    An extrusion process was developed that is able to consistently produce large quantities of Mo-Si-B rods without the presence of defects. Binder removal from the extruded rods was studied in detail and it was determined that heating rates on the order of 0.02{degree}/minute (1.2{degree}/hour) are necessary to remove the binder without the formation of defects. This low heating rate resulted in debinding times in excess of 70 hours (approximately 3 days). Wicking was investigated as a means to decrease the time necessary for binder removal. Using 0.05{micro}m alumina powder as a wicking agent, binder removal times were reduced to 10 hours with heating rates up to 1{degree}/minute employed without defect formation. Once the extrusion process was complete the oxidation properties of the Tl-MoSi{sub 2}-MoB extruded phase assemblage was investigated. It was determined that this composition exhibits catastrophic oxidation or pesting in the temperature range of 660--760 C, resulting in the material turning to dust. Outside of this temperature range the composition is oxidatively stable. Continuous mass measurements were taken at 1,300, 1,450, and 1,600 C to determine the oxidation rate constants of this material. Parabolic rate constants of 6.9 x 10{sup {minus}3}, 1.3 x 10{sup {minus}3}, and 9.1 x 10{sup {minus}3} mg{sup 2}/cm{sup 4}/hr were determined for 1,300, 1,450, and 1,600 C respectively.

  20. Processing of Mo-Si-B intermetallics by extrusion and oxidation properties of the extruded Tl-MoSi2-MoB Systems

    International Nuclear Information System (INIS)

    An extrusion process was developed that is able to consistently produce large quantities of Mo-Si-B rods without the presence of defects. Binder removal from the extruded rods was studied in detail and it was determined that heating rates on the order of 0.02degree/minute (1.2degree/hour) are necessary to remove the binder without the formation of defects. This low heating rate resulted in debinding times in excess of 70 hours (∼ 3 days). Wicking was investigated as a means to decrease the time necessary for binder removal. Using 0.05microm alumina powder as a wicking agent, binder removal times were reduced to 10 hours with heating rates up to 1degree/minute employed without defect formation. Once the extrusion process was complete the oxidation properties of the Tl-MoSi2-MoB extruded phase assemblage was investigated. It was determined that this composition exhibits catastrophic oxidation or pesting in the temperature range of 660--760 C, resulting in the material turning to dust. Outside of this temperature range the composition is oxidatively stable. Continuous mass measurements were taken at 1,300, 1,450, and 1,600 C to determine the oxidation rate constants of this material. Parabolic rate constants of 6.9 x 10-3, 1.3 x 10-3, and 9.1 x 10-3 mg2/cm4/hr were determined for 1,300, 1,450, and 1,600 C respectively

  1. Deformability properties of timolol-loaded transfersomes based on the extrusion mechanism. Statistical optimization of the process.

    Science.gov (United States)

    González-Rodríguez, M L; Arroyo, C M; Cózar-Bernal, M J; González-R, P L; León, J M; Calle, M; Canca, D; Rabasco, A M

    2016-10-01

    The purpose of this work was to analyze the deformability properties of different timolol maleate (TM)-loaded transfersomes by extrusion. This was performed because elastic liposomes may contribute to the elevation of amount and rate of drug permeation through the corneal membrane. This paper describes the optimization of a transfersome formulation by use of Taguchi orthogonal experimental design and two different statistical analysis approaches were utilized. The amount of cholesterol (F1), the amount of edge-activator (F2), the distribution of the drug into the vesicle (F3), the addition of stearylamine (F4) and the type of edge-activator (F5) were selected as causal factors. The deformability index, the phosphorous recovery, the vesicle size, the polydispersity index, the zeta potential and percentage of drug entrapped were fixed as the dependent variables and these responses were evaluated for each formulation. Two different statistical analysis approaches were applied. The better statistical approach was determined by comparing their prediction errors, where regression analysis provided better optimized responses than marginal means. From the study, an optimized formulation of TM-loaded transfersomes was prepared and obtained for the proposed ophthalmic delivery for the treatment of open angle glaucoma. It was found that the lipid to surfactant ratio and type of surfactant are the main key factors for determining the flexibility of the bilayer of transfersomes. From in vitro permeation studies, we can conclude that TM-loaded transfersomes may enhance the corneal transmittance and improve the bioavailability of conventional TM delivery. PMID:26981839

  2. Extrusion die and method

    Science.gov (United States)

    Lipp, G. Daniel

    1994-04-26

    A method and die apparatus for manufacturing a honeycomb body of rhombic cell cross-section by extrusion through an extrusion die of triangular cell discharge slot configuration, the die incorporating feedholes at selected slot intersections only, such that slot segments communicating directly with the feedholes discharge web material and slot segments not so connected do not discharge web material, whereby a rhombic cell cross-section in the extruded body is provided.

  3. γ-TiAl金属间化合物细晶棒材挤压变形工艺%Extrusion Process of Fine Grained γ-TiAl Alloy Bar

    Institute of Scientific and Technical Information of China (English)

    高帆; 李臻熙

    2014-01-01

    结合数值模拟与工艺试验的方法研究了γ-TiAl合金细晶棒材挤压工艺,获得了挤压过程中各场变量的分布规律及不同挤压比组合下挤压棒材中温度场、应变速率场、等效应变场和断裂因子分布的信息。结果表明,采用3.5+4.3两步挤压比组合时可以获得较为均匀的温度场、应变速率场和等效应变场,且断裂因子数值较小。采用该挤压比组合进行了挤压工艺试验,通过这种两步挤压组合可以获得质量良好,晶粒尺寸细小、均匀的γ-TiAl合金挤压棒材。%The numerical simulation and ex-periment is employed to study the extrusion process of ifne grained TiAl alloy bar. It gets the distribution of each ifeld variable in the extrusion process, and obtains the ifeld vari-able about temperature field, strain rate field, equivalent strain ifeld, and breaking factor distribution under different extrusion ratios. The results show that 3.5+4.3 two-step extrusion ratio is beneifcial to homogeneity of above-men-tioned distribution of ifelds. Extrusion experiment is em-ployed based on the prediction to verify those conclusions of the simulation work. Assuredly, crack-free extrusion bar is obtained, and homogeneous and reifned microstructure are observed.

  4. Method and apparatus for forming billets from metallic chip scraps

    Science.gov (United States)

    Girshov, Vladimir Leonidovich; Treschevskiy, Arnold Nikolayevich; Kochkin, Victor Georgievich; Abramov, Alexey Alexandrovich; Sidenko, Natalja Semenovna

    2006-05-02

    After recycled titanium alloy chips are crushed and cleaned, they are pressed into cylindrically briquettes with a relative density of 0.6, and placed into capsules. The capsules are heated and placed into a preheated pressing rig. The pressing rig repetitively applies axial force to the capsule, resulting in a relative density of at least 0.95. The product billets are used for consumable electrodes, secondary casting alloys, forgings, extruded semi-finished products and the like.

  5. The comparative study of pressing and extrusion like processes of construction ceramic products in the Metropolitan Area of Cucuta; Estudio comparativo de las tecnicas de extrusion y prensado como procesos de conformado de productos ceramicos de construccion en el Area Metropolitana de Cucuta

    Energy Technology Data Exchange (ETDEWEB)

    Gelves, J. F.; Monroy, R.; Sanchez, J.; Ramirez, R. P.

    2013-02-01

    The present work studies the principal variables of control in the manufacturing process of construction pieces of the Metropolitan Area of San Jose de Cucuta by extrusion and pressing techniques for its forming. The investigation was taken out using clayey samples of the two principal geological formations of the region where the raw material is taken for processing at an industrial level. The clayey samples milling was made by dry means as well as by moisture means and its particle size was measured. Subsequently the forming process was taken over by using an hydraulic press and extruder with vacuum system , both equipment s at laboratory scale, the pieces shaped were dry and firing between 980 degree centigrade and 1180 degree centigrade at the end of the process the tests were made to determine water absorption, contraction and mass loss at the pieces firing. The study results left to see that the extrusion technique allowed a faster vitrification for the region's clay in comparing with the pressing technique, the contractions of drying and firing are less marked on the pressing techniques with standard deviations much lower than in extrusion. (Author) 13 refs.

  6. The Influence of Extrusion Ratio on W-40 % Cu Alloy Produced by Powder Canning Hot Extrusion%挤压比对粉末包套热挤压致密W-40%Cu合金的影响

    Institute of Scientific and Technical Information of China (English)

    李达人; 蔡一湘; 刘祖岩; 王尔德

    2012-01-01

    采用不同挤压比对W-40%Cu混合粉末进行粉末包套热挤压,获得了W--40%Cu合金.研究了模具总挤压比λ对热挤压坯料致密化以及组织性能的影响.结果表明,随着挤压比的增加,热挤压坯料的相对密度也增加,同时电导率和硬度值也随之提高.由于含铜量比较高(质量分数为40%),即便在挤压比为25时,挤压坯内部W相也不发生变形,主要是铜相产生变形.进一步将模具总挤压比λ细分为不考虑体积变形的坯料总挤压比α,除去体积变形因素的坯料塑性挤压比β以及包套挤压比γ三种实际挤压比,分析了不同挤压比对热挤压致密化过程的影响.%W-40 wt.%Cu alloys with different extrusion ratio have been obtained by powder canning hot extrusion. The experimental results show that, the relative density, specific conductance and hardness of the billets increase with the adding extrusion ratio. There is no shape change of W phase after powder canning hot extrusion even if the extrusion ratio is up to 25 due to high content of Cu phase (40 wt.%). The deformation mainly occurs in Cu phase. The total extrusion ratio (λ) is divided into three kinds of actual extrusion ratio: the extrusion ratio of billet (α) without considering the volumetric deformation; the plastic extrusion ratio (β) excluding the influence of volumetric deformation; the extrusion ratio of can (γ). This article studies the influence of these three kinds of actual extrusion ratio on the densification of W-40 wt.% Cu alloy by powder canning hot extrusion.

  7. Solidification Structure of Continuous Casting Large Round Billets under Mold Electromagnetic Stirring

    Institute of Scientific and Technical Information of China (English)

    Tao SUN; Feng YUE; Hua-jie WU; Chun GUO; Ying LI; Zhong-cun MA

    2016-01-01

    The solidification structure of a continuous casting large round billet was analyzed by a cellular-automaton-finite-element coupling model using the ProCAST software.The actual and simulated solidification structures were compared under mold electromagnetic stirring (MEMS)conditions (current of 300 A and frequency of 3 Hz).There-after,the solidification structures of the large round billet were investigated under different superheats,casting speeds,and secondary cooling intensities.Finally,the effect of the MEMS current on the solidification structures was obtained under fixed superheat,casting speed,secondary cooling intensity,and MEMS frequency.The model accurately simulated the actual solidification structures of any steel,regardless of its size and the parameters used in the continuous casting process.The ratio of the central equiaxed grain zone was found to increase with decreasing su-perheat,increasing casting speed,decreasing secondary cooling intensity,and increasing MEMS current.The grain size obviously decreased with decreasing superheat and increasing MEMS current but was less sensitive to the casting speed and secondary cooling intensity.

  8. CNC Extruder for varied section extrusion

    Directory of Open Access Journals (Sweden)

    H.J. Choi

    2008-08-01

    Full Text Available Purpose: The work presented in this paper might be used for basic data in the design of a lot extruded aluminum products using the variable section extrusion process.Design/methodology/approach: The capacity of a CNC extruder was calculated and decided as analyzing the FEM results performed by commercial software DEFORM-2D. CNC extruder and die set for variable section extrusion was invented by field extrusion experts.Findings: CNC extruder had a key role in variable extrusion process. Furthermore there was few die sets with mold feeding parts for aluminum extrusion. To be capable of extruding aluminum products with variable cross section are CNC extruder and the die set.Research limitations/implications: For future research of developed CNC extruder, frame structures of the extruder would be analyzed and designed using FE analysis. In addition CNC extruder would be operated by the control program for variable section as a PC version.Practical implications: Aluminum parts with variable section would increase as utilizing the CNC extruder and cost price of the parts be down. Many industrial products using the variable section extrusion process would be used in diverse fields.Originality/value: Extruded aluminum part with variable section is rarely used since extruders don’t be designed and developed for variable section extrusion. It is important that an extruder with CNC control, which could be easily handled and have accessible software to be operated by field user, are invented. As stated above, CNC extruder is needed for production of industrial products with variable section for today. Therefore design and development of CNC extruder having the die set for mold feeding parts was tackled in this paper as efficient approach using commercial FEM code.

  9. CAD implementation of design rules for aluminium extrusion dies

    NARCIS (Netherlands)

    Ouwerkerk, van Gijs

    2009-01-01

    Aluminium extrusion is an industrial forming process that is used to produce long profiles of a constant cross-section. This cross-section is shaped by the opening in a steel tool known as the die. The understanding of the mechanics of the aluminium extrusion process is still limited. The flow of al

  10. 挤出法制备乳剂的工艺优化%Preparation of emulsions by extrusion and optimization of process

    Institute of Scientific and Technical Information of China (English)

    蒋宫平; 骆翔; 程晓波; 佘振南; 宋艳志; 邓意辉

    2013-01-01

    Objective To optimize the process of emulsion using extrusion method.Methods The emulsion was prepared by extruder.In the orthogonal design,mean diameter and coeff.of var'n were selected as evaluation variables,membrane pore,cycle times,temperature and pressure were employed as independent variables.The optimal process was predicted by orthogonal design,and then the sterilization stability,frozen stability and centrifugation stability of emulsion were predicted by the optimal process.Results The mean diameter and coeff.of var'n of the optimal preparation were (116.7 ± 2.2) nm and (0.453 ± 3.400),respectively,and the stability of sterilization,frozen and centrifugation were fine.Conclusions Extrusion is a suitable method for preparing emulsion with small particle size,uniform distribution and good stability;this method has a great prospect in preparing thermally unstable substance emulsion.%目的 确定挤出法制备乳剂的最优工艺.方法 经挤出仪制备乳剂,采用正交设计法,以乳剂的平均粒径、变异系数为评价指标,考察了乳剂挤出工艺中滤膜孔径、挤出次数、温度及压力对制剂的影响,及最优工艺制得乳剂的离心稳定性、灭菌稳定性和冻融稳定性.结果 采用优化挤出工艺制得乳剂的平均粒径为(116.7 ±2.2)nm,变异系数为(0.453 ±3.400),且离心稳定性、灭菌稳定性和冻融稳定性良好.结论 挤出法可以制备粒径小、粒度分布均匀、稳定性良好的乳剂,该方法在热不稳定性药物乳剂的制备中具有很大的应用前景.

  11. Development of Extrusion Technology and Its Application in Electrical Materials Production%挤压技术的发展及其在电工材料生产中的应用

    Institute of Scientific and Technical Information of China (English)

    刘伟利; 陈乐生

    2013-01-01

    The application of extrusion technologies in electrical materials production is summarized. Three conventional extrusion technologies are detailed, including horizontal extrusion, hydrostatic extrusion and continuous extrusion. This paper emphasizes the principles, characteristics and development status of the three extrusion technologies, as well as their applications in the electrical materials production. Some other extrusion technologies such as powder extrusion, multi-billet extrusion and combined extrusion are briefly introduced also. Finally, the development trend of the extrusion technologies in electrical materials production is previewed.%总结了挤压技术在电工材料生产中的应用概况。详细介绍了三种常见工业挤压技术--卧式挤压、静液挤压和连续挤压,重点阐述了这三种挤压技术的原理特点、发展状况及其在电工材料生产中的应用;简单介绍了其他挤压技术,包括粉末挤压、多坯料挤压、复合挤压等,展望了挤压技术在电工材料生产方面的发展趋势。

  12. Microstructure stability of ultra-fine grained magnesium alloy AZ31 processed by extrusion and equal-channel angular pressing (EX–ECAP)

    Energy Technology Data Exchange (ETDEWEB)

    Stráská, Jitka, E-mail: straska.jitka@gmail.com [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Praha 2 (Czech Republic); Janeček, Miloš, E-mail: janecek@met.mff.cuni.cz [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Praha 2 (Czech Republic); Čížek, Jakub, E-mail: jcizek@mbox.troja.mff.cuni.cz [Department of Low Temperature Physics, Faculty of Mathematics and Physics, Charles University in Prague, V Holešovičkách 2, 180 00 Praha 8 (Czech Republic); Stráský, Josef, E-mail: josef.strasky@gmail.com [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Praha 2 (Czech Republic); Hadzima, Branislav, E-mail: branislav.hadzima@fstroj.uniza.sk [University of Žilina, Research Centre, Univerzitná 1, 010 26 Žilina (Slovakia); Department of Materials Engineering, Faculty of Mechanical Engineering, University of Žilina, Univerzitná 1, 010 26 Žilina (Slovakia)

    2014-08-15

    Thermal stability of the ultra-fine grained (UFG) microstructure of magnesium AZ31 alloy was investigated. UFG microstructure was achieved by a combined two-step severe plastic deformation process: the extrusion (EX) and subsequent equal-channel angular pressing (ECAP). This combined process leads to refined microstructure and enhanced microhardness. Specimens with UFG microstructure were annealed isochronally at temperatures 150–500 °C for 1 h. The evolution of microstructure, mechanical properties and dislocation density was studied by electron backscatter diffraction (EBSD), microhardness measurements and positron annihilation spectroscopy (PAS). The coarsening of the fine-grained structure at higher temperatures was accompanied by a gradual decrease of the microhardness and decrease of dislocation density. Mechanism of grain growth was studied by general equation for grain growth and Arrhenius equation. Activation energies for grain growth were calculated to be 115, 33 and 164 kJ/mol in temperature ranges of 170–210 °C, 210–400 °C and 400–500 °C (443–483 K, 483–673 K and 673–773 K), respectively. - Highlights: • Microhardness of UFG AZ31 alloy decreases with increasing annealing temperature. • This fact has two reasons: dislocation annihilations and/or grain growth. • The activation energies for grain growth were calculated for all temperature ranges.

  13. Evaluation of the Possibility of Performing Cold Backward Extrusion of Axisymmetrical Thinwalled Aluminum Die Stampings with Square Section / Ocena Możliwości Wyciskania Przeciwbieżnego Na Zimno Osiowosymetrycznych Wyprasek Z Cienką Ścianką O Przekroju Kwadratowym Z Aluminium

    Directory of Open Access Journals (Sweden)

    Miłek T.

    2015-12-01

    Full Text Available The paper presents evaluation of the possibility of performing cold backward extrusion of axisymmetrical thin-walled aluminum (Al 99.50, ENAW-1050A die stampings with a square section at the strain ε=ln(A0/A1=2 (where A0 - cross sectional area of the billet, A1 - cross sectional area of the die stamping, and the ratio h1/b=3.6 (where h1 - height of the die stamping in mm, b - width of the base of the die stamping in mm. The analysis was conducted on the basis of the results of computer modelling (FEM and experimental investigations on backward extrusion. The boundary conditions for numerical calculations were determined experimentally with respect to the flow curve and mechanical properties of aluminum. The results of investigations into backward extrusion of thin-walled square-sectioned aluminum die stampings might be used as guidelines to develop a technological process for industrial practice.

  14. Extrusion cast explosive

    Science.gov (United States)

    Scribner, Kenneth J.

    1985-01-01

    Improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst are disclosed. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants.

  15. Modelling of contact and friction in aluminium extrusion

    NARCIS (Netherlands)

    Ma, X.; Rooij, de M.B.; Schipper, D.J.

    2010-01-01

    A physical model capable of predicting the friction and sticking/slipping lengths in the bearing channel during unlubricated aluminium extrusion processes is presented. The model takes into account the pressure build up in the extrusion direction in relation with the bearing–extrudate friction and h

  16. 大型无缝铝管材固定针挤压工艺研究%R&D on fixed-mandrel extrusion process of large-size seamless aluminium tube

    Institute of Scientific and Technical Information of China (English)

    张君; 韩炳涛; 李正利; 黄胜; 胡阳虎; 唐照环

    2012-01-01

    The different methods of seamless aluminium tube extrusion process were introduced. The fixed-mandrei extrusion process used for large-size seamless aluminiun tube was researched by theoretical analyses, numerical simulation and experimental. The mechanics statue of mandrel in fixed-mandrel process was analyzed. The mechanics calculation equation of fixed-mandrel were set up and the pressure equations of rod cavity of mandrel cylinder were gained. Based on the established FE model, the simulation and analysis has been carried out for the extrusion processes of a large size aluminium seamless lube in fixed-mandrel extrusion. The variation curve of pulling force on mandrel vs. ram displacement of fixed-mandrel for large-size seamless tube extrusion has been obtained. A technical route used for realizing fixed-mandrel process for large size seamless tube has also been put forward. The experiment research has been carried out on the 55 MN aluminun extrusion press with oil-driven double action.%介绍了几种无缝铝管材挤压工艺,采用理论分析、数值模拟与实验研究相结合的方法,对大型无缝铝管材固定针挤压工艺进行了研究.分析了固定针挤压时穿孔针的受力情况,建立了穿孔针受力的力学计算公式,得出了穿孔油缸系统压力变化公式.采用有限元数值模拟的方法,对无缝铝管材固定针挤压工艺进行了数值模拟,揭示了无缝铝管材挤压过程中穿孔针上拉力与行程曲线的变化规律,据此,提出了实现无缝铝管材固定针挤压工艺的技术路线.研究结果在55 MN油压双动短行程铝挤压机上进行了实验验证.

  17. Numerical simulation on rolling-extrusion forming of variable thickness cylinder%变壁厚筒形构件辊挤成形过程数值模拟

    Institute of Scientific and Technical Information of China (English)

    赵熹; 张治民; 张宝红

    2014-01-01

    为解决变壁厚筒体构件制造过程材料利用率低、机加工时长等问题,提出一种辊挤成形工艺。该工艺通过3个被动旋转辊轮的辊压作用实现坯料的塑性变形。借助Deform-3D软件建立变壁厚筒形构件辊挤成形热力耦合刚黏塑性有限元模型,对辊挤过程进行数值模拟,获得了辊挤过程中载荷-行程曲线、等效应力与应变场以及温度场的分布规律。研究了工艺参数对成形构件变形均匀性的影响。结果表明:工件变形的不均匀性随着辊挤速度和摩擦因数的增大而增大,随变形温度的升高而减小。%The rolling-extrusion technique for the mass production of variable wall thickness cylinder parts was put forward for reducing the machining time and increasing the material utilization. In this process,material was formed by means of three passively rotational tools. A coupled thermal-mechanical rigid-viscoplasticity FEM model for rolling-extrusion of variable thickness cylinder parts was developed based on the Deform-3D software. The distribution of equivalent strain field,equivalent stress field, temperature field and the load-stroke curve during the rolling-extrusion forming process was obtained. Furthermore,the influence of process parameters on the deformation uniformity was analyzed. The results show that the deformation nonuniformity of billet increases with the increase of punch speed and friction factor,and with the decrease of initial temperature of billet.

  18. 利用反应挤出技术改善淀粉基聚合物性能的研究%Application of Reactive Extrusion in Starch-based Polymer Processing

    Institute of Scientific and Technical Information of China (English)

    刘莉

    2012-01-01

    淀粉基聚合物的开发利用很大程度地减轻了环境污染,具有广阔的应用前景.鉴于反应挤出技术在改变产品的结构和化学性质方面极具优势,综述了反应挤出技术在淀粉基接枝共聚物和纳米复合材料等多相复合体系中的发展应用.%Development of starch-based polymer reduces the environmental pollution to a large extent and has broad application prospect. In view that the reactive extrusion technology has many advantages in modifying structure and chemical properties of polymer during processing, this paper focuses on the application of reactive extrusion in starch-based polymer processing, which includes graft copolymers and nanocom- posites.

  19. Equal Channel Angular Extrusion of AA 6063 Using Conventional Direct Extrusion Press

    Science.gov (United States)

    Liu, Cheng-Hsien; Lin, Hsin-Chih

    2015-11-01

    In the present work, an extrusion-equal channel angular extrusion (Ex-ECAE) process composed of two processes, extrusion and ECAE, is developed. The Ex-ECAE die contains three segments and is used directly in the conventional direct extrusion press to refine the microstructure, specifically the coarse grain layer (CGL) on the surface of the extrudate. The first segment in the die is designed to perform the normal extrusion process and the second and third segments to perform the process of ECAE. The study reveals that the CGL can be eliminated (refined) completely at the macroscale. At the microscale, the original grain is subdivided into subgrain, which contains many smaller cells. The results can be explained by the grain subdivision mechanism. The textures of the Ex-ECAE sample at various segments are measured using EBSD (Electron Backscatter Diffraction). The results reveal that the first segment of the Ex-ECAE sample has a perfect fiber texture which consists of a mixture of strong and weak fiber components. The texture of the second segment is a mixture of strong (1 1 0) [1 -2 1] and weak (0 1 1) [2 -1 0] fiber components. However, the main component of the second segment is a typical texture of the "alloy" or "brass" type. Finally, the texture of the extrudate (the third segment) is reversed to an incomplete fiber texture which consists of strong (0 0 1) [-1 -1 0] and weak (1 1 1) [1 -1 0].

  20. Extrusion process of non-rotator contact pedestal and its die%非回转体触头座挤压成形工艺与模具设计

    Institute of Scientific and Technical Information of China (English)

    郜建新; 赵培峰; 宋克兴

    2013-01-01

    The extrusion process of non-rotator contact pedestal of a high-voltage switch was analyzed. The structure of two-operation extrusion die and the design method of main components were presented. The die has a simple structure and a small deformation force.%  研究了高压开关触头座外形为非回转体的挤压成形工艺,介绍了采用两道工序挤压模结构及主要模具零件的设计方法,挤压成形的零件尺寸及形状精度达到了设计要求,模具结构简单,变形力小,提高了生产效率。

  1. A study of ultrasonic property variations within jet-engine nickel alloy billets

    International Nuclear Information System (INIS)

    A summary is presented of an ongoing project to measure the UT properties of jet-engine nickel alloy billets and to correlate their properties with the local billet microstructure. To date, measurements have been performed on four 'strip' coupons cut from three different Nickel alloy billets (IN718 and Waspaloy). Longitudinal-wave velocities, attenuation, backscattered noise capacity (FOM) have been measured at selected sites for two propagation directions. The UT results are consistent with equiaxed microstructures in which the mean grain diameter varies with radial depth. The grain diameter at selected sites is determined from detailed metallographic studies and compared with that estimated from the measured attenuation

  2. Estimation of design space for an extrusion-spheronization process using response surface methodology and artificial neural network modelling.

    Science.gov (United States)

    Sovány, Tamás; Tislér, Zsófia; Kristó, Katalin; Kelemen, András; Regdon, Géza

    2016-09-01

    The application of the Quality by Design principles is one of the key issues of the recent pharmaceutical developments. In the past decade a lot of knowledge was collected about the practical realization of the concept, but there are still a lot of unanswered questions. The key requirement of the concept is the mathematical description of the effect of the critical factors and their interactions on the critical quality attributes (CQAs) of the product. The process design space (PDS) is usually determined by the use of design of experiment (DoE) based response surface methodologies (RSM), but inaccuracies in the applied polynomial models often resulted in the over/underestimation of the real trends and changes making the calculations uncertain, especially in the edge regions of the PDS. The completion of RSM with artificial neural network (ANN) based models is therefore a commonly used method to reduce the uncertainties. Nevertheless, since the different researches are focusing on the use of a given DoE, there is lack of comparative studies on different experimental layouts. Therefore, the aim of present study was to investigate the effect of the different DoE layouts (2 level full factorial, Central Composite, Box-Behnken, 3 level fractional and 3 level full factorial design) on the model predictability and to compare model sensitivities according to the organization of the experimental data set. It was revealed that the size of the design space could differ more than 40% calculated with different polynomial models, which was associated with a considerable shift in its position when higher level layouts were applied. The shift was more considerable when the calculation was based on RSM. The model predictability was also better with ANN based models. Nevertheless, both modelling methods exhibit considerable sensitivity to the organization of the experimental data set, and the use of design layouts is recommended, where the extreme values factors are more represented

  3. Numerical Simulation for Canning Extrusion Process of FGH96%FGH96合金包覆挤压过程数值模拟

    Institute of Scientific and Technical Information of China (English)

    朱兴林; 刘东; 杨艳慧; 牛关梅

    2013-01-01

    The configuration and dimension of the die are critical for canning extrusion of FGH96 P/M superalloy. In this paper, the influence of die angle, band length and entrance fillet of the dies on the canning integrality, extrusion ratio of the core, and extrusion force were analyzed comprehensively by using FEM and orthogonal method. The results of FEM numerical simulation and orthogonal a-nalysis indicate that the integrality of canning and extrusion ratio of the core were improved with the decrease in die angle, band length and increase in entrance fillet of the die. The optimal combination of the structural parameters of the extrusion die was obtained.%采用有限元数值模拟与正交设计相结合的方法对热等静压态FGH96合金包覆挤压过程进行了数值模拟,系统分析了模具模角、工作带长度、入口圆角半径等模具关键结构参数对包覆层完整性、芯料挤压比和成形载荷的影响规律.确定了模具结构参数的最佳组合.结果表明:随着模角的减小、工作带长度的缩短和入口圆角半径的增大,有利于提高包覆层安全性,增大芯料挤压比.

  4. Formation of Chromosomal Domains by Loop Extrusion.

    Science.gov (United States)

    Fudenberg, Geoffrey; Imakaev, Maxim; Lu, Carolyn; Goloborodko, Anton; Abdennur, Nezar; Mirny, Leonid A

    2016-05-31

    Topologically associating domains (TADs) are fundamental structural and functional building blocks of human interphase chromosomes, yet the mechanisms of TAD formation remain unclear. Here, we propose that loop extrusion underlies TAD formation. In this process, cis-acting loop-extruding factors, likely cohesins, form progressively larger loops but stall at TAD boundaries due to interactions with boundary proteins, including CTCF. Using polymer simulations, we show that this model produces TADs and finer-scale features of Hi-C data. Each TAD emerges from multiple loops dynamically formed through extrusion, contrary to typical illustrations of single static loops. Loop extrusion both explains diverse experimental observations-including the preferential orientation of CTCF motifs, enrichments of architectural proteins at TAD boundaries, and boundary deletion experiments-and makes specific predictions for the depletion of CTCF versus cohesin. Finally, loop extrusion has potentially far-ranging consequences for processes such as enhancer-promoter interactions, orientation-specific chromosomal looping, and compaction of mitotic chromosomes. PMID:27210764

  5. Formation of Chromosomal Domains by Loop Extrusion

    Directory of Open Access Journals (Sweden)

    Geoffrey Fudenberg

    2016-05-01

    Full Text Available Topologically associating domains (TADs are fundamental structural and functional building blocks of human interphase chromosomes, yet the mechanisms of TAD formation remain unclear. Here, we propose that loop extrusion underlies TAD formation. In this process, cis-acting loop-extruding factors, likely cohesins, form progressively larger loops but stall at TAD boundaries due to interactions with boundary proteins, including CTCF. Using polymer simulations, we show that this model produces TADs and finer-scale features of Hi-C data. Each TAD emerges from multiple loops dynamically formed through extrusion, contrary to typical illustrations of single static loops. Loop extrusion both explains diverse experimental observations—including the preferential orientation of CTCF motifs, enrichments of architectural proteins at TAD boundaries, and boundary deletion experiments—and makes specific predictions for the depletion of CTCF versus cohesin. Finally, loop extrusion has potentially far-ranging consequences for processes such as enhancer-promoter interactions, orientation-specific chromosomal looping, and compaction of mitotic chromosomes.

  6. Ram speed profile design for isothermal extrusion of AZ31 magnesium alloy by using FEM simulation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In the conventional hot extrusion of metallic materials,the temperature of the workpiece varies during the whole extrusion process,leading to the non-uniformity of the product dimension,microstructure and properties.In the present research,a simulation model based on the principle of PID control was developed to establish ram speed profiles that can suppress the temperature evolution during the process to allow for isothermaI extrusion.With this simulation model,the real-time extrusion ram speed was adjusted according to the simulated exit temperature.The results show that temperature homogeneity is significantly improved not only along the extrudate length but also on its cross section in the case of extrusion in the isothermal mode with a designed ram speed profile in the extrusion process of AZ31 magnesium.In addition,die temperature varies over a more narrow range in comparison with extrusion in the conventional iso-speed mode.

  7. Calibrator device for the extrusion of cable coatings

    Science.gov (United States)

    Garbacz, Tomasz; Dulebová, Ľudmila; Spišák, Emil; Dulebová, Martina

    2016-05-01

    This paper presents selected results of theoretical and experimental research works on a new calibration device (calibrators) used to produce coatings of electric cables. The aim of this study is to present design solution calibration equipment and present a new calibration machine, which is an important element of the modernized technology extrusion lines for coating cables. As a result of the extrusion process of PVC modified with blowing agents, an extrudate in the form of an electrical cable was obtained. The conditions of the extrusion process were properly selected, which made it possible to obtain a product with solid external surface and cellular core.

  8. The stability of beam with two billeting arbitrarily, but symmetrical support under action of follow loading

    Directory of Open Access Journals (Sweden)

    V.Ts. Gnuni

    2016-03-01

    Full Text Available The non-conservative stability problem of pressing beam when two support billeting symmetrical on arbitrarily distance from the end is considered. It is show the possibility statical form loss of stability. The critical loads are determined.

  9. Volume calculation of the spur gear billet for cold precision forging with average circle method

    Institute of Scientific and Technical Information of China (English)

    Wangjun Cheng; Chengzhong Chi; Yongzhen Wang; Peng Lin; Wei Liang; Chen Li

    2014-01-01

    Forging spur gears are widely used in the driving system of mining machinery and equipment due to their higher strength and dimensional accuracy. For the purpose of precisely calculating the volume of cylindrical spur gear billet in cold precision forging, a new theoretical method named average circle method was put forward. With this method, a series of gear billet volumes were calculated. Comparing with the accurate three-dimensional modeling method, the accuracy of average circle method by theoretical calculation was estimated and the maximum relative error of average circle method was less than 1.5%, which was in good agreement with the experimental results. Relative errors of the calculated and the experimental for obtaining the gear billet volumes with reference circle method are larger than those of the average circle method. It shows that average circle method possesses a higher calculation accuracy than reference circle method (traditional method), which should be worth popularizing widely in calculation of spur gear billet volume.

  10. Design and performance of the Savannah River Site Billet Active Well Coincidence Counter

    International Nuclear Information System (INIS)

    The Savannah River Site (SRS) has acquired, installed, and tested a custom-built Billet Active Well (neutron) Coincidence Counter (BAWCC). The BAWCC is used to make accountability measurements of the 235U content of U-Al coextrusion billets in the SRS fuel fabrication facility. The instrument design incorporates a unique center-source configuration, with two moderated americium-lithium (AmLi) neutron sources located in a central spindle that inserts through the center hole of the U-Al billets. This configuration, a result of earlier experimental studies at SRS, yields improved response and precision for billet assay when compared to the standard AWCC source arrangement. Initial tests of the BAWCC at SRS have yielded one-sigma uncertainties of 0.8--1.0% for a fifteen-minute assay. This paper will describe the design, testing program and performance characteristics of the BAWCC

  11. Semisolid casting with ultrasonically melt-treated billets of Al-7mass%Si alloys

    Directory of Open Access Journals (Sweden)

    Yoshiki Tsunekawa

    2012-02-01

    Full Text Available The demand for high performance cast aluminum alloy components is often disturbed by increasing impurity elements, such as iron accumulated from recycled scraps. It is strongly required that coarse plate-like iron compound of モ-Al5FeSi turns into harmless form without the need for applying refining additives or expensive virgin ingots. The microstructural modification of Al-7mass%Si alloy billets with different iron contents was examined by applying ultrasonic vibration during the solidification. Ultrasonically melt-treated billets were thixocast right after induction heating up to the semisolid temperature of 583 ìC, the microstructure and tensile properties were evaluated in the thixocast components. Globular primary メ-Al is required to fill up a thin cavity in thixocasting, so that the microstructural modification by ultrasonic melt-treatment was firstly confirmed in the billets. With ultrasonic melt-treatment in the temperature range of 630 ìC to 605 ìC, the primary メ-Al transforms itself from dendrite into fine globular in morphology. The coarse plate-like モ-Al5FeSi compound becomes markedly finer compared with those in non-treated billets. Semisolid soaking up to 583 ìC, does not appreciably affect the size of モ-Al5FeSi compounds; however, it affects the solid primary メ-Al morphology to be more globular, which is convenient for thixocasting. After thixocasting with preheated billets, eutectic silicon plates are extremely refined due to the rapid solidification arising from low casting temperature. The tensile strength of thixocast samples with different iron contents does not change much even at 2mass% of iron, when thixocast with ultrasonically melt-treated billets. However, thixocast Al-7mass%Si-2mass%Fe alloy with non-treated billets exhibits an inferior strength of 80 MPa, compared with 180 MPa with ultrasonically melt-treated billets. The elongation is also improved by about a factor of two in thixocastings with

  12. Analysis, design, and implementation of a logical proof-of-concept prototype for streamlining the advertisement of billets for the U.S. Marine Corps Reserve

    OpenAIRE

    Thorpe, John M.

    2008-01-01

    The primary objective of this thesis is to provide the Marine Corps with a thorough bottom up System Analysis of the next generation billet advertisement system that will replace Reserve Duty Online (RDOL). The study includes a detailed systems analysis, a generic architecture, logical data models, process models and a system model which provides the Marine Corps with a blueprint of the requirements for the next system of record. The secondary objective of this thesis was to analyze curr...

  13. Eulerian hydrocode modeling of a dynamic tensile extrusion experiment (u)

    Energy Technology Data Exchange (ETDEWEB)

    Burkett, Michael W [Los Alamos National Laboratory; Clancy, Sean P [Los Alamos National Laboratory

    2009-01-01

    Eulerian hydrocode simulations utilizing the Mechanical Threshold Stress flow stress model were performed to provide insight into a dynamic extrusion experiment. The dynamic extrusion response of copper (three different grain sizes) and tantalum spheres were simulated with MESA, an explicit, 2-D Eulerian continuum mechanics hydrocode and compared with experimental data. The experimental data consisted of high-speed images of the extrusion process, recovered extruded samples, and post test metallography. The hydrocode was developed to predict large-strain and high-strain-rate loading problems. Some of the features of the features of MESA include a high-order advection algorithm, a material interface tracking scheme and a van Leer monotonic advection-limiting. The Mechanical Threshold Stress (MTS) model was utilized to evolve the flow stress as a function of strain, strain rate and temperature for copper and tantalum. Plastic strains exceeding 300% were predicted in the extrusion of copper at 400 m/s, while plastic strains exceeding 800% were predicted for Ta. Quantitative comparisons between the predicted and measured deformation topologies and extrusion rate were made. Additionally, predictions of the texture evolution (based upon the deformation rate history and the rigid body rotations experienced by the copper during the extrusion process) were compared with the orientation imaging microscopy measurements. Finally, comparisons between the calculated and measured influence of the initial texture on the dynamic extrusion response of tantalum was performed.

  14. Influence of ECAP process on mechanical and corrosion properties of pure Mg and ZK60 magnesium alloy for biodegradable stent applications.

    Science.gov (United States)

    Mostaed, Ehsan; Vedani, Maurizio; Hashempour, Mazdak; Bestetti, Massimiliano

    2014-01-01

    Equal channel angular pressing (ECAP) was performed on ZK60 alloy and pure Mg in the temperature range 150-250 °C. A significant grain refinement was detected after ECAP, leading to an ultrafine grain size (UFG) and enhanced formability during extrusion process. Comparing to conventional coarse grained samples, fracture elongation of pure Mg and ZK60 alloy were significantly improved by 130% and 100%, respectively, while the tensile strength remained at high level. Extrusion was performed on ECAP processed billets to produce small tubes (with outer/inner diameter of 4/2.5 mm) as precursors for biodegradable stents. Studies on extruded tubes revealed that even after extrusion the microstructure and microhardness of the UFG ZK60 alloy were almost stable. Furthermore, pure Mg tubes showed an additional improvement in terms of grain refining and mechanical properties after extrusion. Electrochemical analyses and microstructural assessments after corrosion tests demonstrated two major influential factors in corrosion behavior of the investigated materials. The presence of Zn and Zr as alloying elements simultaneously increases the nobility by formation of a protective film and increase the local corrosion damage by amplifying the pitting development. ECAP treatment decreases the size of the second phase particles thus improving microstructure homogeneity, thereby decreasing the localized corrosion effects. PMID:25482411

  15. Extrusion and properties of lead zirconate titanate piezoelectric ceramics

    DEFF Research Database (Denmark)

    Cai, S.; Millar, C.E.; Pedersen, L.;

    1997-01-01

    The purpose of this work was to develop a procedure for fabricating electroceramic actuators with good piezoelectric properties. The preparation of lead zirconate titanate (PZT) piezoelectric ceramic rods and tubes by extrusion processing is described. The microstructure of extrudates was investi......The purpose of this work was to develop a procedure for fabricating electroceramic actuators with good piezoelectric properties. The preparation of lead zirconate titanate (PZT) piezoelectric ceramic rods and tubes by extrusion processing is described. The microstructure of extrudates...

  16. Encapsulation of Liquids Via Extrusion--A Review.

    Science.gov (United States)

    Tackenberg, Markus W; Kleinebudde, Peter

    2015-01-01

    Various encapsulation techniques are known for pharmaceutical applications. Extrusion is of minor importance. However, extrusion is used to obtain granules with encapsulate liquid active ingredients (AI) like essential oils and flavours for food applications since decades. Many of these AIs can be used for agrochemical, home care, and pharmaceutical products, too. Thus, the focus of this review is on the interdisciplinary presentation and evaluation of the available knowledge about the encapsulation process via extrusion. The desired microcapsule structure is discussed at the outset. The microcapsule is compared to the alternative glassy solid solution system, before an overview of suitable excipients is given. In the next section the development of the extrusion technique, used for encapsulation processes, is presented. Thereby, the focus is on encapsulation using twin-screw extruders. Additionally, the influence of the downstream processes on the products is discussed, too. The understanding of the physical processes during extrusion is essential for specifically adjustment of the desired product properties and thus, highlighted in this paper. Unfortunately not all processes, especially the mixing process, are well studied. Suggestions for further studies, to improve process understanding and product quality, are given, too. The last part of this review focuses on the characterization of the obtained granules, especially AI content, encapsulation efficiency, and storage stability. In conclusion, extrusion is a standard technique for flavour encapsulation, but future studies, may lead to more (pharmaceutical) applications and new products.

  17. Extrusion Cooking Systems and Textured Vegetable Proteins

    OpenAIRE

    1985-01-01

    Many fabricated foods are cooked industrially and are given desired textures, shapes, density and rehydration characteristics by an extrusion cooking process. This relatively new process is used in the preparation of “engineered” convenience foods: textured vegetable proteins, breakfast cereals, snacks, infant foods, dry soup mixes, breading, poultry stuffing, croutons, pasta products, beverage powders, hot breakfast gruels, and in the gelatinization of starch or the starchy component of ...

  18. Use of paprika oily extract as pre-extrusion colouring of rice extrudates: impact of processing and storage on colour stability.

    Science.gov (United States)

    Gat, Yogesh; Ananthanarayan, Laxmi

    2016-06-01

    Suitability of paprika oily extract as a pre-extrusion colouring of rice extrudate was evaluated as a function of extrusion parameters viz. moisture content, screw speed and die temperature. Most acceptable coloured rice extrudates in terms of colour and overall acceptability was achieved with addition of 3 % paprika oily extract and which is extruded at fixed conditions of 25 % feed moisture, 120 °C barrel temperature and 100 rpm screw speed. During extrusion, retention of red colour of paprika oily extract added rice extrudates increased with an increase in feed moisture and screw speed while decreased with an increase in barrel temperature. Present study was also undertaken to check effect of addition of butylated hydroxytoluene (BHT) on colour stability of coloured rice extrudates. Coloured rice extrudates were packed in polyethylene, metallised polyethylene and vacuum packaging material and subjected to storage studies for 90 days at 25 and 50 °C with 65 % relative humidity conditions. Retention of red colour (a*) of paprika oily extract added rice extrudates follows first order kinetics, showing a faster rate of degradation with half-life of 48 days when packed in metalized polyethylene and stored at higher temperature conditions. PMID:27478245

  19. Hot extrusion of B2 iron aluminide powders

    Science.gov (United States)

    Strothers, S.; Vedula, K.

    1987-01-01

    The objective of the study was to investigate the effect of powder and processing variables on the microstructure and resultant tensile properties of an extruded FeAlZrB alloy. For a given powder particle size, increasing the extrusion temperature from 1250 to 1450 K is found to increase the grain size and produce a more uniform microstructure. At high extrusion temperatures, where grain boundary mobility is high, powder size is not critical in determining the grain size. The addition of Y2O3 dispersion (1 vol pct) by mechanical alloying makes it possible to obtain very fine-grained materials at low and high extrusion temperatures.

  20. DYNAMIC MODELS FOR HOT-EXTRUSION OF POLYESTER FIBRE

    Directory of Open Access Journals (Sweden)

    G. M. Irapetiants

    2014-01-01

    Full Text Available The paper considers modeling of dynamics on hot extrusion process for polyester fibre. New modifications of nonlinear dynamic models are have been proposed in the paper. The models in contrast with the known ones make it possible to take into account an effect of tensile stress magnitude and duration of its application on temperature of the hot extrusion, in order to achieve the desired values of strength and relative elongations of the polyester fibre. The proposed models are applicable for efficient solution of problems on synthesis of combined control systems for regulation of hot extrusion temperature.

  1. Influence of hot rolling and high speed hot extrusion process on the microstructure and properties of R and A ODS ferritic steel

    International Nuclear Information System (INIS)

    Full text: Argon gas atomized, pre-alloyed Fe-14Cr-2W-0.3Ti oxide dispersion strengthened (ODS) ferritic steel powder was mechanically alloyed with 0.3Y2O3 (wt.%) nano-particles in attritor ball mill and consolidated by hot isostatic pressing (HIP) at 1150 deg. C under pressure of 200 MPa for 3 hrs. To improve mechanical properties of as HIPped ODS ingots the material was undergone further thermo-mechanical treatment (TMT), namely: hot rolling (HR) at 850 oC or high speed hot extrusion (HSHE) at 850 deg. C. After TMT both materials were annealed at 1050 deg. C for 1 h in vacuum. Transmission electron microscopy (TEM) observations of the ODS alloys after TMT and heat treatment exhibited elongated in a longitudinal direction grains with an average size of 75 μm. However, an equiaxed, smaller than 500 nm grains were also found in the microstructure of both materials. Different size and morphology of oxides particles were also observed. Bigger, about 150 nm Ti-Al-O particles were usually located at grain boundaries whereas Y-Ti-O nanoclusters of about 5 nm were uniformly distributed in ODS steel matrix. The Charpy impact tests revealed significantly better about 90% (5.8 J) upper shelf energy (USE) of material after HSHE but ductile to brittle transition temperature (DBTT) of both alloys was unsatisfactory. As-HR ODS steel has shown DBTT of about 55 deg. C whereas HSHE ODS steel has about 75 deg. C. This relatively high values of transition temperature were probably caused by oxides particles present at grain boundaries of the ODS alloys which decreased fracture properties of the ODS steels. High temperature tensile properties of both ODS alloys are found to be satisfactory in full range of the testing temperature from 23 up to 750 deg. C. However, about 15% better UTS and YS0.2 (1350 MPa and 1285 MPa, respectively) as well as ductility were measured in the case of the as-HSHE ODS steel. These results indicates that HSHE process of the ODS steel can be considered as

  2. Application of the Billet Casting Method to Determine the Onset of Incipient Melting of 319 Al Alloy Engine Blocks

    Science.gov (United States)

    Lombardi, A.; Ravindran, C.; MacKay, R.

    2015-06-01

    The increased use of Al for automotive applications has resulted from the need to improve vehicle fuel efficiency. Aluminum alloy engine blocks fulfil the need of lightweighting. However, there are many challenges associated with thermo-mechanical mismatch between Al and the gray cast iron cylinder liners, which result in large tensile residual stress along the cylinder bores. This requires improced mechanical properties in this region to prevent premature engine failure. In this study, replicating billet castings were used to simulate the engine block solution heat treatment process and determine the onset of incipient melting. Microstructural changes during heat treatment were assessed with SEM and EDX, while thermal analysis was carried out using differential scanning calorimetry. The results suggest that solution heat treatment at 500 °C was effective in dissolving secondary phase particles, while solutionizing at 515 or 530 °C caused incipient melting of Al2Cu and Al5Mg8Cu2Si6. Incipient melting caused the formation ultra-fine eutectic clusters consisting of Al, Al2Cu, and Al5Mg8Cu2Si6 on quenching. In addition, DSC analysis found that incipient melting initiated at 507 °C for all billets, although the quantity of local melting reduced with microstructural refinement as evidenced by smaller endothermic peaks and energy absorption. The results from this study will assist in improving engine block casting integrity and process efficiency.

  3. Experimental Investigation of Extrusion Process of Double-lumen Micro Tube%聚合物双腔微管挤出成型工艺试验研究

    Institute of Scientific and Technical Information of China (English)

    靳国宝; 王敏杰; 赵丹阳; 田慧卿

    2012-01-01

    The extrusion of multi-lumen micro tube with small size, uneven thicknesses and complex section shape is difficult, so double-lumen micro tube with different cavity shapes is taken as the research object. A trace ventilation system is introduced to the extrusion process, and non-symmetric flow balance design method and fine electrical discharge machining(EDM) machining technology are used to design and manufacture the right angle extrusion die. Then, effects of extrusion process parameters on the shape accuracy of double-lumen micro tube, evaluated by the ellipticity of profiles and uniformity of wall thicknesses, are investigated experimentally, taking polypropylene as extrusion material. Experimental results show that the effects of gas flow rates, screw speed, die temperature, tank vacuum and drawing speed on the ellipticity of products weaken in order. However, the thickness uniformity of products depends mainly on the extrusion die, and it is hardly influenced by the changes in process parameters. Through the analysis of experimental results, the action mechanisms of the above process parameters on the product deformation are revealed. The optimum combination of process parameters is concluded, and double-lumen micro tubes which meet the design requirements are obtained.%针对尺寸小、壁厚不均匀、截面形状复杂的多腔微管挤出成型难度大的问题,以双腔异形微管为研究对象,在挤出过程中引入微量注气系统,采用非对称流动平衡设计方法和微细电火花成型加工技术,设计制造双腔异形微管直角挤出模具.以聚丙烯为试验材料,以双腔微管制品截面的轮廓椭圆度和壁厚均匀度为评价指标,研究微管挤出成型中主要工艺参数对制品形状精度的影响规律.试验结果表明,型腔注气量、螺杆转速、模具温度、水箱真空度和牵引速度对制品椭圆度的影响依次减弱;制品壁厚均匀度主要取决于挤出模具,基本不受工艺

  4. Production of extremely deep sleeves by backward cold extrusion

    Directory of Open Access Journals (Sweden)

    Labanova Nadja

    2015-01-01

    Full Text Available The production of extremely deep sleeves by backward cold extrusion has drawn significant attention and interest in recent years in metal forming area, due to their unique and superior properties and their economic and technological advantages. This work describes the limitation related to buckling of extrusion punch during backward extrusion process and also represents the design of a new tool concept to avoid such risks of effects. Application of this tool concept for many cases in industry provides new opportunities to produce deep sleeves with ratio of the overall height of a sleeve (H to its inner diameter (d higher than three within one process stage by backward cold extrusion. Developed concept of tool has been supported by previous fundamental and applied research studies.

  5. Effect of original microstructures on microstructural evolution of A2017 semi-solid alloy billets during reheating

    Institute of Scientific and Technical Information of China (English)

    WANG Shun-cheng; CAO Fu-rong; WEN Jing-lin

    2005-01-01

    The microstructural evolution of the A2017 semi-solid alloy billets provided with rheocasting and extruding/extending forming by shearing-cooling-rolling(SCR) technology during reheating in semi-solid state was investigated. The microstructural differences and their generation causes for both billets were also analyzed. The results show that during reheating, the grains of rheocasting billets grow up and spheroidize gradually with the prolongation of isothermal holding time, the eutectic liquid phase at low melting point forms mainly among the grains. However, the grains of the extruding/extending forming billets grow up abnormally through grain coalescence in the initial stage of the reheating, the entrapment of large amount of liquid within grains occurs, and the grain sizes in the reheating billets are coarse and inhomogeneous. Compared with extruding/extending forming billets, rheocasting billets have smaller and uniform grains in reheating microstructure and can rapidly form liquid phase among grains. Therefore, rheocasting billets are more suitable for the semi-solid forming than the extruding/extending forming billets.

  6. Qualitative modelling of starch products expansion by extrusion

    OpenAIRE

    David, C.

    2014-01-01

    In spite of the versatility, soberness and safety of extrusion process, and of the industrial importance of the area, the design of extruded foods still relies predominantly on empirical approaches. Although tools are available to transfer scientific knowledge, like Ludovic©, a software for simulating twin screw corotative extruder, there is a lack of generic model to predict cellular structure from extrusion and material variables. A bottle-neck with that regard is the modelling of the expan...

  7. Fabrication and properties of binder for powder extrusion molding

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    By optimizing formulation and fabrication methods, a new binder for plasticizing powder extrusion molding ofhard metal, with excellent integrated properties and uniform distribution characters, has been developed. Thermal debond-ing mechanism and the extruding rheological behaviours have been studied. The technology of fabrication of binder andthermal debonding process have also been investigated. Using the novel binder, the hard-metal extrusion-molding rods withdiameter up to 25mm, have been manufactured.

  8. An ANN/GA(Artificial Neural Network/Genetic Algorithm)for Modeling and Optimizing of Liquid Metal Extrusion Process%液态挤压工艺ANN/GA建模与优化研究

    Institute of Scientific and Technical Information of China (English)

    齐乐华; 侯俊杰; 杨茂奎; 李贺军

    2001-01-01

    Forming quality of liquid metal extrusion process has been difficult to ensure. We resolved this difficult problem by proposing modeling with artificial neural network (ANN) and optimization of process parameters with genetic algorithm (GA) . Fig.1 shows the neural network model that can make the five process parameters selected compatible: (1) pouring temperature (T1), (2) die temperature ( T2), (3) pressing velocity (v), (4) delaying period before applying p ressure (t), (5) deforming force (F). Then we optimized the five parameters with GA and obtained T1=716℃, T2=250℃, t=30 s, v≈2.6 ×10-3 m/s, Fmin=86.6 MPa for a liquid AlCuSiMgalloy extrusion . These predi cted optimal values agreed well with test results.%利用人工神经网络方法(ANN)建立了工艺系统模型,用遗传算法(GA)对过程参数进行优化, 实验结果与预测值吻合良好, 为预测和控制该工艺成形质量提供了行之有效的手段。

  9. Effect of Extrusion Cooking on Bioactive Compounds in Encapsulated Red Cactus Pear Powder

    OpenAIRE

    Ruiz-Gutiérrez, Martha G.; Carlos A. Amaya-Guerra; Armando Quintero-Ramos; Esther Pérez-Carrillo; Teresita de J. Ruiz-Anchondo; Juan G. Báez-González; Meléndez-Pizarro, Carmen O.

    2015-01-01

    Red cactus pear has significant antioxidant activity and potential as a colorant in food, due to the presence of betalains. However, the betalains are highly thermolabile, and their application in thermal process, as extrusion cooking, should be evaluated. The aim of this study was to evaluate the effect of extrusion conditions on the chemical components of red cactus pear encapsulated powder. Cornstarch and encapsulated powder (2.5% w/w) were mixed and processed by extrusion at different bar...

  10. The friction in rod forward and backward micro extrusion

    Directory of Open Access Journals (Sweden)

    J. Piwnik

    2010-01-01

    Full Text Available Micro parts are increasingly applied in industry because of the trend to miniaturization every day devices. Microforming is a method of manufacturing metal micro elements using a plastic treatment. This kind of production ensures high productivity, shapes and dimensions repeatability and good surface quality. Size effect connected with small dimensions affects changes in treatment processes of micro parts. While forming in micro scale, surface roughness is size independent and does not decrease with decreasing detail dimensions. The article presents schemas for forward and backward extrusion of metal rods. Using FEM, tool’s roughness as a triangle wave has been assumed, taking into account thereby size effect. Influence of roughness on extrusion forces by comparison with traditional flat tools and constant friction shear factor m has been specified. Impact of roughness caused growth of extrusion forces while forward extruding. On the contrary, backward extrusion ensured stable required forces, regardless of a surface structure.

  11. Role of Nonmonotonic Constitutive Curves in Extrusion Instabilities

    Directory of Open Access Journals (Sweden)

    Yu Cao

    2015-01-01

    Full Text Available Flow instabilities of non-Newtonian fluids severely hamper the quality of products during various chemical processes, such as fibre spinning, extrusion, and film blowing. The origin of extrusion instability has been studied over many decades. However, no consensus has been reached among the research community so far. In this paper, the possible cause of extrusion instabilities is explored using the finitely extensible nonlinear elastic conformation-dependent (FENE-CD model with a nonmonotonic constitutive curve. Many well-documented experimental phenomena are reproduced in our simulations, and it could be concluded that the nonmonotonic constitutive curve plays an essential role in extrusion instabilities. In addition, the results imply that the die exit singularity may generate or magnify oscillations.

  12. Apoptotic regulation of epithelial cellular extrusion

    OpenAIRE

    De Andrade, Daniel,; Rosenblatt, Jody

    2011-01-01

    Cellular extrusion is a mechanism that removes dying cells from epithelial tissues to prevent compromising their barrier function. Extrusion occurs in all observed epithelia in vivo and can be modeled in vitro by inducing apoptosis in cultured epithelial monolayers. We established that actin and myosin form a ring that contracts in the surrounding cells that drives cellular extrusion. It is not clear, however, if all apoptotic pathways lead to extrusion and how apoptosis and extrusion are mol...

  13. Hot Extrusion Process Effect on Mechanical Behavior of Stir Cast Al Based Composites Reinforced with Mechanically Milled B4C Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    A. Alizadeh1; E. Taheri-Nassaj; M. Hajizamani

    2011-01-01

    In this study, aluminum alloy (Al-2 wt% Cu) matrix composites reinforced with 1, 2 and 4 wt% boron carbide nanoparticles fabricated through mechanical milling with average size of 100 nm were fabricated via stir casting method at 850℃. Cast ingots of the matrix alloy and the composites were extruded at 500℃ at an extrusion ratio of 10:1 to investigate the effects of hot extrusion on the mechanical properties of the composites. The microstructures of the as-cast and the extruded composites were investigated by scanning electron microscopy (SEM). Density measurement, hardness and tensile tests were carried out to identify the mechanical properties of the composites. The extruded samples revealed a more uniform distribution of B4C nanoparticles. Also, the extruded samples had strength and ductility values superior to those of the as-cast counterparts. In the as-cast and the extruded samples, with increasing amount of B4C nanoparticles, yield strength and tensile strength increased but elongation to fracture decreased.

  14. Study on Numerical Simulation of Hot Extrusion Process of Automobile's Hollow Front Axle%汽车前桥空心短轴的热挤压成形工艺数值模拟研究

    Institute of Scientific and Technical Information of China (English)

    韦国强; 管延锦; 朱立华; 解振东; 孙德朋

    2016-01-01

    A hot extrusion process was proposed to improve the productivity and the material utilization in the manufacture of automobile's hollow front axle . Numerical simulations under various conditions designed by the orthogonal method were done to optimize parameters of the final step of hot extrusion process . Finally the production efficiency , material utilization and product quality were improved and the optimal shaping quality was achieved .%针对某汽车前桥短轴类零件成形制造中存在的生产效率和材料利用率低的问题,提出并设计了热挤压成形制造工艺。通过正交法设计多组参数条件进行数值模拟,实现了热挤压终成形工步的工艺参数优化,获得了最优的成形效果,达到了提高生产效率、材料利用率以及零件质量的目标。

  15. High strength Al–Al2O3p composites: Optimization of extrusion parameters

    DEFF Research Database (Denmark)

    Luan, B.F.; Hansen, Niels; Godfrey, A.;

    2011-01-01

    Composite aluminium alloys reinforced with Al2O3p particles have been produced by squeeze casting followed by hot extrusion and a precipitation hardening treatment. Good mechanical properties can be achieved, and in this paper we describe an optimization of the key processing parameters. The...... investigation of their mechanical properties and microstructure, as well as on the surface quality of the extruded samples. The evaluation shows that material with good strength, though with limited ductility, can be reliably obtained using a production route of squeeze casting, followed by hot extrusion and a...... precipitation hardening treatment. For the extrusion step optimized processing parameters have been determined as: (i) extrusion temperature=500°C–560°C; (ii) extrusion rate=5mm/s; (iii) extrusion ratio=10:1....

  16. Defect detection for corner cracks in steel billets using a wavelet reconstruction method.

    Science.gov (United States)

    Jeon, Yong-Ju; Choi, Doo-chul; Lee, Sang Jun; Yun, Jong Pil; Kim, Sang Woo

    2014-02-01

    Presently, automatic inspection algorithms are widely used to ensure high-quality products and achieve high productivity in the steelmaking industry. In this paper, we propose a vision-based method for detecting corner cracks on the surface of steel billets. Because of the presence of scales composed of oxidized substances, the billet surfaces are not uniform and vary considerably with the lighting conditions. To minimize the influence of scales and improve the accuracy of detection, a detection method based on a visual inspection algorithm is proposed. Wavelet reconstruction is used to reduce the effect of scales. Texture and morphological features are used to identify the corner cracks among the defective candidates. Finally, the experimental results show that the proposed algorithm is effective in detecting corner cracks on the surfaces of the steel billets. PMID:24562019

  17. Improvement of center segregation in high-carbon steel billets using soft reduction

    Institute of Scientific and Technical Information of China (English)

    Wenjun Wang; Xionggang Hu; Linxin Ning; Raimund Bülte; Wolfgang Bleck

    2006-01-01

    Center segregation is the main reason for cup fracture of high-carbon wire rod during drawing. Therefore, to continuously produce cast billets with very low center segregation is an important objective. The soft reduction technology is considered to be an effective method to minimize center segregation. To elucidate the effect of soft reduction on the internal quality of high-carbon steel billets, soft reduction was applied with different solid fractions in the core area of billets in a laboratory casting machine. A coupled temperature/displacement finite element model was developed to calculate the solid fraction using the commercial software ABAQUS.Center segregation, center porosity, homogeneity of elements, and equiaxed crystal zone were obviously improved by applying soft reduction, especially when the solid fraction was less than 1.0. The optimal results were obtained when the solid fraction was approximately 0.9.

  18. Cyclic expansion-extrusion (CEE): A modified counterpart of cyclic extrusion-compression (CEC)

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted Highlights: · Introducing a new severe plastic deformation method. · Imposing high amounts of strains per pass. · Developing well homogenized strain on the cross section of the processed materials. - Abstract: A new method of severe plastic deformation, cyclic expansion-extrusion (CEE), is introduced; CEE is considered as a substitute for the well-known, cyclic extrusion-compression (CEC), by implementing its advantage which is processing samples for the desired number of passes with no need to remove them from the die until the whole number of passes are accomplished. In addition, no external back-pressure system is needed which is the main advantage of this process compared to CEC. This modified process was performed experimentally on aluminum alloy 1050 and was also investigated by finite element analysis. Results reveal that, performing CEE makes it possible to impose large strain values per pass while maintaining a homogeneous hardness distribution in the sample's cross section as well.

  19. 双螺杆挤压机工艺参数对组织蛋白的影响%Effect of Processing Variables of Twin-screw Extrusion to Texturization of Compound Soybean Protein

    Institute of Scientific and Technical Information of China (English)

    王洪武; 周建国; 林炳鉴

    2001-01-01

    本文采用新型双螺杆食品挤压机,进行了挤压加工大豆组织蛋白和工程肉制品的试验研究,获得了螺杆转速、含水量和温度对挤压过程和产品组织化质量的影响规律。研究表明:螺杆转速在80r/min~100r/min之间,含水量在38%~44%之间,大豆组织蛋白的挤压组织化质量良好;螺杆转速在60r/min~80r/min之间,含水量在60%~65%之间,工程肉制品的挤压组织化质量良好:优化的机筒温度和机头温度分布为:30℃~45℃~80℃~100℃~130℃~150℃~100℃。%The effect of processing variables,such as screw speed,feed moisture and barrel tcmperature of extrusion process to the property of extrudate was experimentally studied using a new co-rotating twin-screw cooking extruder.The optimum screw speed was in the range of 80 r/min~120 r/min and the optimum feed moisture was in the range of 34%~44% for extrusion texturization of defatted soybean flour.The optimum processing variable for extrusion texturization of soybean protein and fresh pork meat blends was as follows:screw speed 60 r/min~80 r/min and feed moisture 60%~65%.The optimum temperature profile of the extruder obtained from these experiments was:30℃~45℃~80℃~100℃~130℃~150℃~100℃。In these processing conditions the textured soy protein and engineering meat product had distinct fiber structure.

  20. Performance of Halogen-Free Flame Retardant Cable and Extrusion Process%试析无卤低烟阻燃电缆性能与挤出工艺

    Institute of Scientific and Technical Information of China (English)

    王冬梅

    2013-01-01

    近年来,我国经济发展迅猛,电缆材料的阻燃技术也随之提高,无卤低烟阻燃将成为电缆行业主要的发展趋势。本文分析了无卤低烟阻燃电缆的结构与性能,阐述了这种电缆在生产过程中使用的挤制工艺。%In recent years, China's economy is rapidly developing, and the flame retardant technology of cable material is also increased. Halogen-free flame retardant will become the major trends in the cable industry. This paper analyzes the structure and property of the halogen-free flame retardant cable, and elaborates the extrusion process of the cable in the production process.

  1. Microstructures and mechanical properties of AZ31-0.1Ca magnesium alloy produced by soft-contact electromagnetic casting and hot extrusion

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    An AZ31-0.1Ca magnesium alloy produced by Soft-contact electromagnetic continuous casting(SEMC) was investigated.The fine homogeneous structure and the precipitated phases were obtained by SEMC.The effects of microalloying of Ca and middle frequency electromagnetic field on AZ31-0.1Ca magnesium alloy were discussed.And the as-cast billets were extruded with different extrusion ratios subsequently.The alloy showed an ultrafine grain size of 2-5 μm due to dynamic recrytallization(DRX) in the course of hot ext...

  2. Experimental and numerical analyses of pure copper during ECFE process as a novel severe plastic deformation method

    Directory of Open Access Journals (Sweden)

    M. Ebrahimi

    2014-02-01

    Full Text Available In this paper, a new severe plastic deformation method called equal channel forward extrusion (ECFE process has been proposed and investigated by experimental and numerical approaches on the commercial pure copper billets. The experimental results indicated that the magnitudes of yield strength, ultimate tensile strength and Vickers micro-hardness have been markedly improved from 114 MPa, 204 MPa and 68 HV as the annealed condition to 269 MPa, 285 MPa and 126 HV after the fourth pass of ECFE process, respectively. In addition, scanning electron microscopy observation of the samples showed that the average grain size of the as-received state which is about 22 μm has been reduced to 1.4 μm after the final pass. The numerical investigation suggested that although one pass ECFE process fabricates material with the mean effective strain magnitude of about 1, the level of imposed effective plastic strain gradually diminishes from the circumference to the center of the deformed billet.

  3. THE COMBINED PROCESSES STUDY FOR MANUFACTURING AIRCRAFT PARTS

    Directory of Open Access Journals (Sweden)

    Mr. Boris N. Maryin

    2016-06-01

    Full Text Available The article is devoted to research of the combined processes of forming tubular billets with various media in the process of bending-expanding, breaking-down -expanding while using thermal effects. The paper discusses the processes of forming tubular billets of hard punches, using elastic-granular materials, the peculiarities of forming tubular billets, while the breaking-down -expanding of crimp in a hard punch using elastic-granular bodies. The article presents experimental studies of the bending-expanding of tubular billets in horn-shaped blanks. The authors established the main features of billet distorting in the combined process. The article shows a diagram of the true distorting distribution in the process of stretching and compression in the horn-shaped blanks. The recommendations allow increasing the bending moment and realizing better shaping. The authors make conclusions about the prospects of the application of combined processes in air and rocket.

  4. Expansion of the whole wheat flour extrusion

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2008-01-01

    A new model framework is proposed to describe the expansion of extrudates with extruder operating conditions based on dimensional analysis principle. The Buckingham pi dimensional analysis method is applied to form the basic structure of the model from extrusion process operational parameters....... Using the Central Composite Design (CCD) method, whole wheat flour was processed in a twin-screw extruder with 16 trials. The proposed model can well correlate the expansion of the 16 trials using 3 regression parameters. The average deviation of the correlation is 5.9%....

  5. Rotational extrusion forming process and design of die for internal spiral spline%螺旋内花键旋转挤压成型工艺与模具设计

    Institute of Scientific and Technical Information of China (English)

    王平; 陈爱华; 蔡永辉

    2011-01-01

    在分析M93汽车超越离合器滑座精锻件结构基础上,确定了螺旋内花键旋转挤压成型工艺,设计了挤压模,介绍了模具结构.设计的挤压模满足实际生产需要,对同类零件的成型具有一定的参考作用.%A rotational extrusion forming process was determined and an ex.sion die was designed for an internal helical spline based on analysis on the structure of fine forgings of M93 automobile overrunning clutch slide.

  6. Análise do desenvolvimento morfológico da blenda polimérica PBT/ABS durante as etapas de mistura por extrusão e moldagem por injeção Analysis of the morphological development of PBT/ABS blends during the extrusion and injection molding processes

    Directory of Open Access Journals (Sweden)

    Edson N. Ito

    2004-06-01

    Full Text Available O enfoque principal deste trabalho foi observar o desenvolvimento da morfologia de fases da blenda binária PBT/ABS e desta blenda compatibilizada pela adição de um copolímero acrílico reativo, durante a etapa de mistura por extrusão e de moldagem por injeção. A evolução da morfologia das blendas, durante a etapa de mistura, foi analisada através do uso de amostras coletadas de uma extrusora de rosca dupla co-rotacional, com acessório especialmente projetado para coleta in line. A morfologia observada nas amostras obtidas por injeção foi realizada utilizando amostras retiradas de corpos de prova moldados. As amostras obtidas por extrusão e por moldagem por injeção foram posteriormente preparadas através de crio-ultramicrotomia e observadas através de microscopia eletrônica de transmissão (TEM. Uma "Função Dispersão" foi desenvolvida neste trabalho para comparar as diversas morfologias sob diferentes condições de processamento e de compatibilização. A adição de compatibilizante favorece a formação de uma morfologia de domínios de ABS dispersos em PBT, ao longo do canhão da extrusora, e previne satisfatoriamente o fenômeno de coalescência destes domínios durante o processo de moldagem por injeção. A função dispersão foi utilizada principalmente para mostrar a tendência da evolução morfológica e mostrou um bom desempenho para tal.The aim of this work was to observe the development of the phase morphology of the PBT/ABS blends during their extrusion mixing and injection molding steps. The evolution of the blend morphology during the mixing stage was analyzed using a specially designed co-rotational twin-screw extruder with a collecting device located along the barrel. Blend samples were collected in-line along the length of the extruder barrel during the blending process. Blend morphology was also observed from specimens molded through injection molding. All the samples were observed by transmission

  7. 新型耐磨锡青铜合金包套挤压工艺及组织性能%Microstructure and properties of wear-resisting Cu-Sn-Pb-Ni alloy prepared by canning extrusion process

    Institute of Scientific and Technical Information of China (English)

    赵培峰; 周延军; 宋克兴; 张彦敏

    2012-01-01

    Directing to the difficulties in the densification of Cu-Sn-Pb-Ni alloy containing 8%~12% tin by conventional plastic forming,the plastic deformation of Cu-Sn-Pb-Ni alloy was carried out by the canning extrusion process.The microstructure and properties of as-cast alloy and as-extruded alloy were analyzed.The as-extruded alloy with the density of 8.98g/cm3 and strength of 345MPa was obtained.The results reveal that the properties of the Cu-Sn-Pb-Ni alloy can be improved via the canning extrusion process.%针对锡含量为8%~12%的锡青铜合金脆性大,难以通过塑性变形实现较高致密度的问题,采用包套挤压工艺制备新型耐磨Cu-Sn-Pb-Ni合金,分析其铸态及包套挤压态的微观组织及性能.包套挤压的密度和硬度分别达到8.98g/cm3和HB135.7;挤压后合金抗拉强度和伸长率分别为345.366MPa和11.4%.结果表明,合金在外加包套作用下塑性有所提高.

  8. Effect of process and machine parameters on physical properties of extrudate during extrusion cooking of sorghum, horse gram and defatted soy flour blends.

    Science.gov (United States)

    Basediya, A L; Pandey, Sheela; Shrivastava, S P; Khan, Khursheed Alam; Nema, Anura

    2013-02-01

    Extrusion cooking of sorghum (Sorghum vulgaris), horse gram (Dolichos biflorus) and defatted soy (Glycine max) flour blends was done to prepare snacks by using a Brabender single-screw laboratory extruder. The combined effect of moisture content, blend ratio of feed, barrel temperature and screw speed of extruder on physical parameters of extrudate was studied. It was observed that 15% moisture content of feed, 80:10:10 (sorghum flour: horse gram flour: defatted soy flour) of blend ratio, 130 °C barrel temperature and 130 rpm of screw speed gave the highest sectional expansion index and longitudinal expansion index of extrudate, while 12% moisture content, 75:15:10 of blend ratio of feed, 135 °C of barrel temperature and 135 rpm of screw speed gave lowest bulk density of extrudate. A central composite rotable design (CCRD) of response surface methodology was used to develop prediction model. Second order quadratic regression model fitted adequately in the variation. The significance was established at p ≤ 0.05. It was also observed that increasing feed moisture content results in a higher density and lower expansion of extrudate. Increasing barrel temperature and screw speed reduced density but increased expansion of extrudate.

  9. The phenomenon of durability variable dies for aluminum extrusion profiles

    Directory of Open Access Journals (Sweden)

    J. Borowski

    2016-04-01

    Full Text Available Extrusion dies are usually regenerated several times (min 4 times. The phenomenon of extended life after each regenerative nitriding process has not been explained. In this work, the regeneration process of dies used in the extrusion of aluminium profiles has been presented. In the article, it was sought to explain the cause of increased die durability after the third or fourth nitriding. Also in this work is presented an analysis of the influence of the parameters of gas nitriding with the ZeroFlow method on hardness of dies. Results were verified under industrial conditions at extrusion company, comparing the durability of the dies nitrided with the ZeroFlow method with so-far-used dies nitrided in the commercial way. An increase of the dies durability was achieved after a single ZeroFlow nitriding.

  10. Numerical Analysis of the Forming Process of Head Toothing in Rolling Extrusion on a Shaft from Aluminum Alloy 7075 / Analiza Numeryczna Kształtowania Uzębienia Czołowego W Procesie Przepychania Obrotowego Na Wałku Ze Stopu Aluminium 7075

    OpenAIRE

    Bartnicki J.; Tomczak J.

    2015-01-01

    This paper presents the forming method of head toothing with the application of rolling extrusion technology. Tools numerical models were used in numerical calculations. The presented numerical results concern metals flow kinematics, distributions of stresses and strains. Determined in the process technological parameters of head toothing forming allow foreseeing real material flow in the experiment planned for conducting.

  11. Numerical Analysis of the Forming Process of Head Toothing in Rolling Extrusion on a Shaft from Aluminum Alloy 7075 / Analiza Numeryczna Kształtowania Uzębienia Czołowego W Procesie Przepychania Obrotowego Na Wałku Ze Stopu Aluminium 7075

    Directory of Open Access Journals (Sweden)

    Bartnicki J.

    2015-12-01

    Full Text Available This paper presents the forming method of head toothing with the application of rolling extrusion technology. Tools numerical models were used in numerical calculations. The presented numerical results concern metals flow kinematics, distributions of stresses and strains. Determined in the process technological parameters of head toothing forming allow foreseeing real material flow in the experiment planned for conducting.

  12. Chemical, physical and nutritional changes in soybean meal as a result of toasting and extrusion cooking.

    NARCIS (Netherlands)

    Marsman, G.J.P.

    1998-01-01

    The effect of soybean meal extrusion and the development of shear forces during single-screw extrusion was compared with the toasting process of soybean meal. Attention was focused on chemical, physical and nutritional changes during these thermo-mechanical treatments.Monitoring target parameters we

  13. Physical properties, molecular structures and protein quality of texturized whey protein isolate: effect of extrusion temperature

    Science.gov (United States)

    Extrusion is a powerful food processing operation, which utilizes high temperature and high shear force to produce a product with unique physical and chemical characteristics. Texturization of whey protein isolate (WPI) through extrusion for the production of protein fortified snack foods has provid...

  14. Numerical Simulation on the Die Filling Process of the Thixo-Forging of Al-7 wt pct Si/Al-22 wt pct Si Bimetal Composite

    Science.gov (United States)

    Wang, Guangxu; Huang, Honghua; Yang, Zhao; Shi, Xiaocheng; He, Xiaolong

    2015-10-01

    A bimetal semi-solid fluid has more complicated flow behaviors than a normal semi-solid fluid during thixo-forging. In order to clarify the detailed properties of the bimetal thixo-forging, the effects of billet temperatures and frictions on flow behaviors of the Al-7 wt pct Si/Al-22 wt pct Si bimetal thixo-forging were investigated by commercial software DEFORM-3D. The simulation results show that shear force was unable to be transferred from the upper billet on the drop die side to the bottom billet on the counter die side efficiently in the initial stage of die filling. Only when the upper billet severely deformed, did the shear force deform the bottom billet. A stiffer upper billet can enhance the efficiency of shear force transfer. The processing temperature, the relative stiffness between the upper billet and bottom billet, and frictions between dies and billets, as well as friction between billets, were important factors to control the interface outline of the bimetal parts. The experimental results are consistent with the simulation results.

  15. Extrusion Processed Polymer Electrolytes based on Poly(ethylene oxide) and Modified Sepiolite Nanofibers: Effect of Composition and Filler Nature on Rheology and Conductivity

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • PEO/ethylene carbonate (EC)/LiTF electrolytes are prepared by extrusion. • Some include also sepiolite nanofibers with ad-hoc surface modifications. • Some of the electrolytes show σ>10−4 S cm−1 at RT and σ> 10−3 S cm−1 at T > 50 °C. • One of them, with EC and one of the nanofibers, is solid-like between 50-90 °C. • Both high σ and mechanical performance are stable for long periods of time. - Abstract: A series of poly(ethylene oxide) (PEO)/lithium trifluoromethanesulfonate(LiTf)/ethylene carbonate(EC)/sepiolite composite electrolytes have been prepared by melt compounding. Neat sepiolite, sepiolite coated with polyethylene glycol and with D-α-tocopherol polyethylene glycol 1000 succinate have been used as fillers, and nanocomposites with different ratio of the components have been prepared. The concentration of EC and LiTf has been progressively increased from low to high values and in this way, electrolytes with conductivities from 2 × 10−6 to 3 × 10−4 S cm−1 at 30 °C have been prepared. Together with conductivity, viscoelasticity has also been studied, evidencing a complex rheological behaviour which depends on the type of filler introduced in the blend. Some of the thermoplastic electrolytes are seen to display a liquid-like conductivity together with solid-like mechanical properties over the melting point of PEO. The solid-like performance is featured by shear moduli crossover G’ = G” at 75 °C at very low frequencies. This combination of properties makes them appealing starting points for the development of solid polymer electrolytes

  16. Effect of extrusion ratio on coating extrusion of Pb-GF composite wire by numerical simulation and experimental investigation

    Institute of Scientific and Technical Information of China (English)

    WANG Xin; SUN Hong-fei; FANG Wen-bin

    2009-01-01

    The extrusion ratio is one of the key parameters for manufacturing the lead-glass fiber (Pb-GF) composite wire by coating extrusion. The effect of extrusion ratio on coating extrusion of Pb-GF composite wire was studied by finite element numerical simulation with the use of the DEFOEM simulation software. The simulation result shows that the higher the extrusion ratio, the higher the effective stress that the glass fiber bears during extrusion. It is also observed that the extrusion force increases with the increase of the extrusion ratio. The extrusion experiment of Pb-GF composite wire reveals that extrusion ratio is changed by changing the quantity of glass fiber and composite diameter. The rule that increasing the extrusion ratio enhances the coating speed limit suggests that the load on the glass fiber increases with increasing extrusion ratio. Both the simulation and the extrusion experiments show that the extrusion force increases with increasing extrusion ratio.

  17. Digestibilidade e atividade enzimática intestinal de coelhos em crescimento alimentados com diferentes fontes de amido processadas ou não por extrusão Digestibility and intestinal enzymatic activity of growing rabbits fed different sources of starch processed or not by extrusion

    Directory of Open Access Journals (Sweden)

    Luciana Kazue Otutumi

    2005-04-01

    Full Text Available Foram conduzidos dois experimentos para avaliar a digestibilidade do amido e a atividade específica das enzimas amilase (ATAM e maltase (ATMAL, em duas porções do intestino delgado (jejuno e íleo, em coelhos com idades iniciais de 28 e 49 dias, alimentados com quatro fontes de amido (milho, sorgo, triticale e mandioca, processados ou não por extrusão. Em cada experimento, foram utilizados 64 coelhos da raça Nova Zelândia Branco, distribuídos em um delineamento inteiramente casualizado com oito tratamentos e oito repetições. Ao final do período experimental, os animais foram abatidos para retirada de amostra do conteúdo do jejuno e íleo, além da raspagem da mucosa do jejuno, para determinação da ATAM e ATMAL. O processamento melhorou o coeficiente de digestibilidade (CD do amido do milho e do sorgo. Entre as fontes não-extrusadas, os maiores CD do amido foram apresentados pelo triticale e pela mandioca. A ATAM da parede do jejuno foi maior aos 60 dias. A ATMAL no conteúdo do jejuno e do íleo foi maior aos 37 dias. As diferentes fontes de amido diferiram entre si quanto à ATMAL e ATAM do conteúdo do jejuno e do íleo. A ATMAL foi maior no jejuno. Maiores ATAM do conteúdo do jejuno ocorreu aos 60 dias para os animais que receberam milho extrusado e sorgo. A ATAM aos 37 dias foi maior no íleo em comparação com o jejuno para os animais que receberam milho e sorgo. O processamento foi efetivo para o milho e sorgo, porém, todas as fontes, processadas ou não, apresentaram bom CD do amido, podendo ser utilizadas na alimentação de coelhos.Two experiments were carried out to study the digestibility of starch and the specific activity of amylase (ACAMY and maltase (ACMAL enzymes in two portions of small intestine (jejunum and ileum, in rabbits with initial ages of 28 and 49 days, fed with four sources of starch (corn, sorghum, triticale and cassava processed or not by extrusion. Sixty-four White New Zealand rabbits were used in

  18. Improving tensile properties of dilute Mg-0.27Al-0.13Ca-0.21Mn (at.%) alloy by low temperature high speed extrusion

    International Nuclear Information System (INIS)

    As-cast Mg-0.27Al-0.13Ca-0.21Mn (at.%) alloy was extruded at temperatures from 350 °C to 500 °C. We examined the microstructural changes during extrusion at different temperatures to clarify dynamic recrystallization mechanisms during extrusion, and also investigated the effect of extrusion temperature on microstructures and mechanical properties of the alloy. High extrusion exit speed of 60 m/min was successfully achieved at wide range of temperatures from 350 °C to 500 °C even when as-cast dilute Mg-0.27Al-0.13Ca-0.21Mn (at.%) alloy was used as a billet for the extrusion. The extrusion at low temperature refines grain size and weakens basal texture due to continuous dynamic recrystallization (CDRX) together with double twinning. As a result, the alloy sample extruded at 350 °C exhibits higher tensile proof stress of 206 MPa and higher tensile ductility of 29% than T5-treated 6063 aluminum alloy and commercial AZ31 magnesium alloy even in an as-extruded condition. Furthermore, Hall–Petch coefficient for compressive proof stress is 1.8 times larger than that for tensile one, resulting in improvement of yield stress anisotropy (compressive proof stress/tensile yield stress ratio). - Highlights: • Dilute Mg–Al–Ca–Mn alloy can be extruded at high die-exit speed of 60 m/min. • The extrusion at low temperature refines recrystallized grain size and weakens basal texture. • Grain refining improves mechanical properties of dilute Mg–Al–Ca–Mn alloys

  19. Improving tensile properties of dilute Mg-0.27Al-0.13Ca-0.21Mn (at.%) alloy by low temperature high speed extrusion

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, T., E-mail: s123055@stn.nagaokaut.ac.jp [Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka 940-2188 (Japan); Mezaki, T.; Xu, C.; Oh-ishi, K. [Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka 940-2188 (Japan); Shimizu, K.; Hanaki, S. [Sankyo Tateyama, Inc., Sankyo Material-Company, 8-3, Nagonoe, Imizu, Toyama 934-8515 (Japan); Kamado, S. [Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka 940-2188 (Japan)

    2015-11-05

    As-cast Mg-0.27Al-0.13Ca-0.21Mn (at.%) alloy was extruded at temperatures from 350 °C to 500 °C. We examined the microstructural changes during extrusion at different temperatures to clarify dynamic recrystallization mechanisms during extrusion, and also investigated the effect of extrusion temperature on microstructures and mechanical properties of the alloy. High extrusion exit speed of 60 m/min was successfully achieved at wide range of temperatures from 350 °C to 500 °C even when as-cast dilute Mg-0.27Al-0.13Ca-0.21Mn (at.%) alloy was used as a billet for the extrusion. The extrusion at low temperature refines grain size and weakens basal texture due to continuous dynamic recrystallization (CDRX) together with double twinning. As a result, the alloy sample extruded at 350 °C exhibits higher tensile proof stress of 206 MPa and higher tensile ductility of 29% than T5-treated 6063 aluminum alloy and commercial AZ31 magnesium alloy even in an as-extruded condition. Furthermore, Hall–Petch coefficient for compressive proof stress is 1.8 times larger than that for tensile one, resulting in improvement of yield stress anisotropy (compressive proof stress/tensile yield stress ratio). - Highlights: • Dilute Mg–Al–Ca–Mn alloy can be extruded at high die-exit speed of 60 m/min. • The extrusion at low temperature refines recrystallized grain size and weakens basal texture. • Grain refining improves mechanical properties of dilute Mg–Al–Ca–Mn alloys.

  20. Mathematical model of determination of die bearing length in design of aluminum profile extrusion die

    Institute of Scientific and Technical Information of China (English)

    闫洪; 王高潮; 夏巨谌; 李志刚

    2004-01-01

    Based on the finite element simulation of profile extrusion process, the effect of local extrusion ratio, die bearing area and the distance between extrusion cylindrical center and local die orfice center on mental flow velocity was investigated. The laws of deformed metalflow on profile extrusion process were obtained. The smaller the local extrusion ratio, the faster the metal flow velocity; the smaller the area of die bearing, the faster the metal flow velocity; the smaller the distance of position of local die orifice(the closer the distance of position of local die orifice from extrusion cylindrical axis), the faster the metal flow velocity. The effect of main parameters of die structure on metal flow velocity was integrated and the mathematical model of determination of die bearing length in design of aluminum profile extrusion die was proposed. The calculated results with proposed model were well compared with the experimental results. The proposed model can be applied to determine die bearing length in design of aluminum profile extrusion die.

  1. Numerical Solution of Heat Tranfer Problem with Flow and Solidification in Round Billet Continuous Casting of Steel

    Institute of Scientific and Technical Information of China (English)

    JiahongGUO; XinHong

    1999-01-01

    In this paper,two dimensional unsteady flow and energy equations are employed for simulation of the flow and heat transfer in round billet continuous casting A numerical method is developed,by using finite volume method and equivalent specific heat method to solve the equations of flow and heat transfer with solidification.The numerical result shows that the method of this paper is efficient for analyzing the flow and heat transfer with solidification of round billet continuous casting.

  2. Extrusion-formed uranium-2.4 wt. % article with decreased linear thermal expansion and method for making the same

    Science.gov (United States)

    Anderson, Robert C.; Jones, Jack M.; Kollie, Thomas G.

    1982-01-01

    The present invention is directed to the fabrication of an article of uranium-2.4 wt. % niobium alloy in which the linear thermal expansion in the direction transverse to the extrusion direction is less than about 0.98% between 22.degree. C. and 600.degree. C. which corresponds to a value greater than the 1.04% provided by previous extrusion operations over the same temperature range. The article with the improved thermal expansion possesses a yield strength at 0.2% offset of at least 400 MPa, an ultimate tensile strength of 1050 MPa, a compressive yield strength of at least 0.2% offset of at least 675 MPa, and an elongation of at least 25% over 25.4 mm/sec. To provide this article with the improved thermal expansion, the uranium alloy billet is heated to 630.degree. C. and extruded in the alpha phase through a die with a reduction ratio of at least 8.4:1 at a ram speed no greater than 6.8 mm/sec. These critical extrusion parameters provide the article with the desired decrease in the linear thermal expansion while maintaining the selected mechanical properties without encountering crystal disruption in the article.

  3. MM98.36 Strain Paths in Extrusion

    DEFF Research Database (Denmark)

    Lindegren, Maria; Wiwe, Birgitte; Wanheim, Tarras

    1998-01-01

    The extrusion process has been investigated for different geometries, in order to study the strain path of different material elements during their movements through the plastic zone. This is done by using the FEM code DEFORM and physical simulation with wax togehter with the coefficient method...

  4. Modelling of friction for high temperature extrusion of aluminium alloys

    NARCIS (Netherlands)

    Wang, L.

    2012-01-01

    In recent years, finite-element (FE) simulations have been extensively used in scientific research and industrial practice to analyse the extrusion process. A basic issue of FE simulations is the accuracy of the results, which is mainly determined by the viscoplastic material behaviour of aluminium

  5. Turbine airfoil fabricated from tapered extrusions

    Science.gov (United States)

    Marra, John J

    2013-07-16

    An airfoil (30) and fabrication process for turbine blades with cooling channels (26). Tapered tubes (32A-32D) are bonded together in a parallel sequence, forming a leading edge (21), a trailing edge (22), and pressure and suction side walls (23, 24) connected by internal ribs (25). The tapered tubes may be extruded without camber to simplify the extrusion process, then bonded along matching surfaces (34), forming a non-cambered airfoil (28), which may be cambered in a hot forming process and cut (48) to length. The tubes may have tapered walls that are thinner at the blade tip (T1) than at the base (T2), reducing mass. A cap (50) may be attached to the blade tip. A mounting lug (58) may be forged (60) on the airfoil base and then machined, completing the blade for mounting in a turbine rotor disk.

  6. A prototype expert system which assigns aviation maintenance personnel to squadron billets

    OpenAIRE

    Alston, Thomas Porter

    1987-01-01

    The technical feasibility of developing an expert system to support the assignment of squadron maintenance personnel to authorized billets is examined by building a prototype system. The rules used by an assistant maintenance officer to assign personnel are analyzed, and a database derived from the OPNAV 1000/2 and EDVR is designed. The prototype is developed for a micro-computer system using an expert system shell, Insight 2+, and is fully integrated with dBase III files

  7. Térence Billeter, L’Empereur jaune, Paris, Les Indes savantes, 2007, 549 pp.

    OpenAIRE

    Billioud, Sébastien

    2008-01-01

    In this book on Huangdi, the Yellow Emperor, the mythical patron figure of Chinese civilization, Térence Billeter presents a meticulously documented study on the Chinese authorities’ use of traditional culture today. His main thesis is that the Beijing regime is in this way seeking to “build an alternative model of modernity to counter the dominant Western one” (p. 432). This nationalist ideology seeks above all to impart a renewed legitimacy to the authorities in rallying their new social ba...

  8. Contrast of FEM and FVM in simulation of complex aluminum extrusion

    Institute of Scientific and Technical Information of China (English)

    LI Da-yong; ZHOU Fei; CHANG Qun-feng; PENG Ying-hong

    2006-01-01

    Extrusion is the key technology to manufacture aluminum profiles and involves complicate metal deformation coupled with temperature changes. The choice of numerical technique plays an important role and is related to the accuracy and effectiveness of extrusion process analyses. In this paper, the extrusion processes of two complex aluminum profiles are simulated with FEM and FVM respectively. The merit and disadvantage of these two methods are analyzed. The finite element method exhibits higher calculation efficiency in the simulation of a lock catch extrusion process. However, due to frequent rezoning in simulation of complex extrusion process, sharp distortion of finite element mesh can decrease computational accuracy. Therefore the volume loss in FEM simulation is larger than that in FVM simulation by five percent. Based on Euler description, the finite volume method employs structured element mesh covering entire material flowing area, which makes it more robust in the simulation of complicate extrusion process. The deformation configuration with FVM is much smoother than that with FEM in the extrusion simulation of a thin-walled aluminum profile, although FVM requires more computation time.

  9. Secondary cooling technology for high-efficiency continuous billet-casting

    Institute of Scientific and Technical Information of China (English)

    CHEN Deng-fu; WEN Liang-ying; DONG Ling-yan

    2007-01-01

    The mathematical model of high-efficiency continuous billet casting was developed,incorporating the effective spraying water coefficient and the effective specific spraying water flowrate of secondary cooling.To realize uniform cooling in secondary cooling zones,the spraying cooling structure and the arrangement of nozzles were redesigned and optimized,and an additional spraying cooling zone was used.A new secondary cooling model of spraying water was built.It was found that the required spraying water flowrate of a cooling zone was related with the casting speed,the casting temperature,the compositions of liquid steel and the cooling water temperature of secondary cooling.The operation of the reformed caster proved that the spraying cooling structure and the new secondary cooling model were suitable,and the casting speed was greatly enhanced.The highest casting speed was(3.8 to 4.0)m/min for billet with a section of 150×150 mm2.The quality and the output of the billet were improved,and the economical benefit was heightened.

  10. GH4169合金反挤压成形模具磨损%Die Wear during Backward Extrusion of GH4169 Profiles

    Institute of Scientific and Technical Information of China (English)

    李伟伟; 余心宏

    2016-01-01

    Based on the modified Archard wear model,the effects of process parameters on the die wear during backward extrusion of GH4169 superalloy were systematically analyzed by numerical simulation.The results show that within the experimental data,the most prone wear area of the punch is rounded corner,the maximum wear depth of the die is decreased with the increase of the radius of rounded corner and billet temperature,but increased with the increase of friction factor.Also the maximum wear depth of the die is de-creased with the increase of speed when the forming speed is less than 100mm /s,but when the forming speed is more than 100mm /s, the maximum wear depth of the die is increased first and then decreased with the increase of forming speed.When the optimal parame-ters are the billet temperature of 1020 ℃,the friction factor of 0.05,the extrusion speed of 100mm /s and the die temperature of 300℃,the wear depth of the die is the smallest,about 9.28 ×10 -3 mm.%基于修正 Archard 磨损模型,采用数值模拟方法系统分析了 GH4169合金反挤压成形过程中各挤压工艺参数对模具磨损的影响规律。结果表明:在选取的参数范围内,挤压凸模最易产生磨损失效的区域为凸模圆角处,模具最大磨损深度随凸模圆角半径及坯料预热温度的增大而降低,随摩擦系数的增大而增大;当挤压速率小于100 mm /s时,模具最大磨损深度随挤压速率的增大而减小,当挤压速率大于100mm /s 时,模具最大磨损深度随挤压速率的增大先增大后减小。最佳工艺参数坯料预热温度1020℃,摩擦系数0.05,变形速率100mm /s,模具预热温度300℃时模具磨损量最小,为9.28×10-3 mm。

  11. Inductive ingot heating for extrusion press applications; Induktive Bolzenerwaermung fuer Strangpressanwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Stefan [I.A.S. Induktions-Anlagen + Service GmbH und Co. KG, Iserlohn (Germany)

    2013-03-15

    Inductive heating of large-format aluminium ingots on modern extrusion press lines generates significant process-engineering benefits. In addition, the proportion of special alloys processed is continuously increasing, accompanied simultaneously by ever smaller production batches, both of which are factors necessitating improvement of and greater flexibility in process-cycle control. This report examines a system concept recently commissioned on one of the world's largest aluminium extrusion presses. (orig.)

  12. Environmental assessment: Transfer of normal and low-enriched uranium billets to the United Kingdom, Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    Under the auspices of an agreement between the U.S. and the United Kingdom, the U.S. Department of Energy (DOE) has an opportunity to transfer approximately 710,000 kilograms (1,562,000 pounds) of unneeded normal and low-enriched uranium (LEU) to the United Kingdom; thus, reducing long-term surveillance and maintenance burdens at the Hanford Site. The material, in the form of billets, is controlled by DOE's Defense Programs, and is presently stored as surplus material in the 300 Area of the Hanford Site. The United Kingdom has expressed a need for the billets. The surplus uranium billets are currently stored in wooden shipping containers in secured facilities in the 300 Area at the Hanford Site (the 303-B and 303-G storage facilities). There are 482 billets at an enrichment level (based on uranium-235 content) of 0.71 weight-percent. This enrichment level is normal uranium; that is, uranium having 0.711 as the percentage by weight of uranium-235 as occurring in nature. There are 3,242 billets at an enrichment level of 0.95 weight-percent (i.e., low-enriched uranium). This inventory represents a total of approximately 532 curies. The facilities are routinely monitored. The dose rate on contact of a uranium billet is approximately 8 millirem per hour. The dose rate on contact of a wooden shipping container containing 4 billets is approximately 4 millirem per hour. The dose rate at the exterior of the storage facilities is indistinguishable from background levels

  13. Environmental assessment: Transfer of normal and low-enriched uranium billets to the United Kingdom, Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    Under the auspices of an agreement between the U.S. and the United Kingdom, the U.S. Department of Energy (DOE) has an opportunity to transfer approximately 710,000 kilograms (1,562,000 pounds) of unneeded normal and low-enriched uranium (LEU) to the United Kingdom; thus, reducing long-term surveillance and maintenance burdens at the Hanford Site. The material, in the form of billets, is controlled by DOE`s Defense Programs, and is presently stored as surplus material in the 300 Area of the Hanford Site. The United Kingdom has expressed a need for the billets. The surplus uranium billets are currently stored in wooden shipping containers in secured facilities in the 300 Area at the Hanford Site (the 303-B and 303-G storage facilities). There are 482 billets at an enrichment level (based on uranium-235 content) of 0.71 weight-percent. This enrichment level is normal uranium; that is, uranium having 0.711 as the percentage by weight of uranium-235 as occurring in nature. There are 3,242 billets at an enrichment level of 0.95 weight-percent (i.e., low-enriched uranium). This inventory represents a total of approximately 532 curies. The facilities are routinely monitored. The dose rate on contact of a uranium billet is approximately 8 millirem per hour. The dose rate on contact of a wooden shipping container containing 4 billets is approximately 4 millirem per hour. The dose rate at the exterior of the storage facilities is indistinguishable from background levels.

  14. 面向节能优化的加热钢坯特征参数模型研%The Research on Characteristic Parameter Model of Billet Heating for Optimizing Retrench Energy

    Institute of Scientific and Technical Information of China (English)

    周里; 杨承志

    2011-01-01

    本文基于钢坯加热的热流密度的慨率密度分布关联加热能耗的原理,提出一种建立加热钢坯表面的热流密度的概率密度分布曲面模型的方法,以期将来能通过调节表征加热能耗的热流密度概率密度分布曲面形状特点,使钢坯加热工艺过程能耗调节具有较好的操控性,达到钢坯加热节能控制之目的.%The method is proposed about building the probability density distribution surface model of heat flux density of surface of billet heating, based on the principle to associate the probability density distribution surface model of heat flux density of surface of billet heating with the heating energy consumption.It is hoped that it can provide the better controllability about adjusting the energy consumption in the process of billet heating and meet requirement of retrench energy sources and control through adjusting the probability density distribution surface figure of heat flux density which can represent the heating energy consumption.

  15. Densification of powder metallurgy billets by a roll consolidation technique

    Science.gov (United States)

    Sellman, W. H.; Weinberger, W. R.

    1973-01-01

    Container design is used to convert partially densified powder metallurgy compacts into fully densified slabs in one processing step. Technique improves product yield, lowers costs and yields great flexibility in process scale-up. Technique is applicable to all types of fabricable metallic materials that are produced from powder metallurgy process.

  16. Compound fabrication technology of semi-solid billet of Al-Si alloy based on SIMA method

    Institute of Scientific and Technical Information of China (English)

    XUE Ke-min; MI Guang-bao; WANG Qing-rui

    2006-01-01

    Based on SIMA, the Al-Si alloy semi-solid billets were successfully fabricated by means of strain inducement and isothermal treatment for AlSi9Mg poured in the range of near-liquidus. Through orthogonal test, the effects of combination action of near-liquidus casting, strain inducement and isothermal treatment on the morphology of primary α-Al phase of AlSi9Mg close to eutectic point were investigated, and the optimal match relation between the processing parameters of solidification, deformation parameters of strain inducement, processing parameters of isothermal treatment and microstructure parameters of semi-solid alloy was established. The results indicate that compared with the single near-liquidus casting or SIMA, the microstructure of primary α-Al phase in AlSi9Mg alloy prepared by compound fabrication process is more homogeneous, with more globular and finer particles,which has average grain size of 40-50 μm and shape factor of greater than 0.75. After holding at 605 ℃ for 30-40 min under a certain cooling rate, increased deformation volume in SIMA benefits the refinement of the grain and the improvement of the morphology for primary phase.

  17. Extrusion Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-10-01

    Full Text Available Bioconversion of lignocellulosic biomass to bioethanol has shown environmental, economic and energetic advantages in comparison to bioethanol produced from sugar or starch. However, the pretreatment process for increasing the enzymatic accessibility and improving the digestibility of cellulose is hindered by many physical-chemical, structural and compositional factors, which make these materials difficult to be used as feedstocks for ethanol production. A wide range of pretreatment methods has been developed to alter or remove structural and compositional impediments to (enzymatic hydrolysis over the last few decades; however, only a few of them can be used at commercial scale due to economic feasibility. This paper will give an overview of extrusion pretreatment for bioethanol production with a special focus on twin-screw extruders. An economic assessment of this pretreatment is also discussed to determine its feasibility for future industrial cellulosic ethanol plant designs.

  18. Surface quality prediction in aluminum extrusion

    NARCIS (Netherlands)

    Rooij, M.B. de; Ma, X.; Bakker, A.J. den; Werkhoven, R.J.

    2011-01-01

    The surface quality of aluminium extrusion products can be hampered by undesired surface features like die lines and pickups. In particular the presence of pickups is considered as undesirable. Surface pickups appear as intermittent torn marks on the aluminium extrusion products, often terminated wi

  19. Effect of Processing Parameters on Microstructure and Mechanical Properties of an Al-Al11Ce3-Al2O3 In-Situ Composite Produced by Friction Stir Processing

    NARCIS (Netherlands)

    Chen, C. F.; Kao, P. W.; Chang, L. W.; Ho, N. J.

    2010-01-01

    Friction stir processing (FSP) was applied to produce aluminum-based in-situ composites from powder mixtures of Al-5 mol pct CeO2. A billet of powder mixtures was prepared using the conventional pressing and sintering route. The sintered billet was then subjected to multiple passages of FSP. This te

  20. Enhancement of Aluminum Alloy Forgings through Rapid Billet Heating

    Energy Technology Data Exchange (ETDEWEB)

    Kervick, R.; Blue, C. A.; Kadolkar, P. B.; Ando, T.; Lu, H.; Nakazawa, K.; Mayer, H.; Mochnal, G.

    2006-06-01

    Forging is a manufacturing process in which metal is pressed, pounded or squeezed under great pressure and, often, under high strain rates into high-strength parts known as forgings. The process is typically performed hot by preheating the metal to a desired temperature before it is worked. The forging process can create parts that are stronger than those manufactured by any other metal working process. Forgings are almost always used where reliability and human safety are critical. Forgings are normally component parts contained inside assembled items such airplanes, automobiles, tractors, ships, oil drilling equipment, engines missiles, and all kinds of capital equipment Forgings are stronger than castings and surpass them in predictable strength properties, producing superior strength that is assured, part to part.

  1. 基于灰色系统理论的推挤成形工艺参数优化%Optimization on processing parameters of extrusion technology based on grey system theory

    Institute of Scientific and Technical Information of China (English)

    林标华; 王鸿基; 陈晨

    2011-01-01

    以推挤成形过程中压料力、冲头速度、摩擦因数和顶件力工艺参数为自变量,以零件底部膨胀厚度、成形载荷为目标函数,进行正交试验,模拟异形孔推挤成形,获得成形工艺参数与零件底部膨胀厚度、成形载荷的多目标函数值.采用灰色系统理论,分析各成形工艺参数与多目标的平均关联度,优化成形工艺参数,获得较优的成形工艺参数组合.结果表明,优化后的工艺参数减少了零件底部膨胀厚度,降低了成形载荷.%The extrusion technology of the shaped hole was numerical simulated by FEM software while blank-holder, punch speed, friction factor, kicking force were independent variables, and the increase in bottom thickness of the part and forming load were objective function, the date about the increase in bottom thickness, forming load were obtained by an orthogonal experiment. The grey system theory was adopted to analyze the average relational degree between process parameters and multi-objective, thus the combination of process parameters were gained through optimization. The result shows that optimized parameters reduce the increase in bottom thickness and forming load.

  2. Numerical simulation on boiling heat transfer of evaporation cooling in a billet reheating furnace

    Institute of Scientific and Technical Information of China (English)

    冯明杰; 王恩刚; 王海; 李艳东; 刘兵

    2016-01-01

    The boiling heat transfer of evaporation cooling in a billet reheating furnace was simulated. The results indicate that the bubbles easily aggregate inside of the elbow and upper side of the horizontal regions in theπshaped support tubes. The circulation velocity increasing helps to improve the uniformity of vapor distribution and decrease the difference of vapor volume fraction between upper and down at end of the horizontal sections. With the increase of circulation velocity, the resistance loss and the circulation ratio both increase, but the former will decrease with the increase of work pressure.

  3. Friction measurement and modelling in forward rod extrusion

    DEFF Research Database (Denmark)

    Tan, Xincai; Bay, Niels; Zhang, Wenqi

    2003-01-01

    experimentally friction stress at various normal pressures, reductions in area, billet heights and lubrications. Tested materials include aluminium alloy, low carbon steel and stainless steel. Two lubrication methods are applied, conversion coating followed by either alkaline soap or molybdenum disulphide...

  4. Effects of Guiding Angle on Plastic Metal Flow and Defects in Extrusion of Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    Shijian YUAN; Feng LI; Zhubin HE

    2008-01-01

    To reduce defects, such as the shrinkage cavity and the surface cracks caused by non-homogeneous metal flow in extrusion process, an extrusion method was proposed by using a die with the guiding angle. Numerical simulation and experiment were conducted to investigate the metal flow in this extrusion process. It is shown that the stress state at the bottom of the die is changed. The tendency to generate the dead zone is decreased by employing the guiding angle at the die entrance. The shrinkage cavity is reduced because the non-homogeneous metal flow at the final stage of extrusion is improved. The axial stress is decreased greatly so that the surface cracks caused by additional stress are avoided.

  5. Twin screw extrusion pre-treatment of wheat straw for biofuel and lignin biorefinery applications

    OpenAIRE

    Ng, Thian Hong

    2013-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Pre-treatment of wheat straw(lignocellulosic) biomass is a crucial step as it has direct impact on the subsequent yield of enzymatic saccharification and alcohol fermentation processes in the production of biofuel. Twin screw extrusion is a highly feasible pretreatment method and has been received great interest in the recent year pre-treatment studies. Twin screw extrusion is a continuous pr...

  6. Improvement of mechanical properties and corrosion resistance of biodegradable Mg–Nd–Zn–Zr alloys by double extrusion

    International Nuclear Information System (INIS)

    Highlights: ► Microstructure of Mg–Nd–Zn–Zr alloys was refined and homogenized by double extrusion process. ► The mechanical properties of the alloys were significantly enhanced by double extrusion. ► The biocorrosion resistance of the alloys was improved by double extrusion. - Abstract: Mg–Nd–Zn–Zr alloy is a novel and promising biodegradable magnesium alloy due to good biocompatibility, desired uniform corrosion mode and outstanding corrosion resistance in simulated body fluid (SBF). However, the corrosion resistance and mechanical properties should be improved to meet the requirement of the biodegradable implants, such as plates, screws and cardiovascular stents. In the present study, double extrusion process was adopted to refine microstructure and improve mechanical properties of Mg–2.25Nd–0.11Zn–0.43Zr and Mg–2.70Nd–0.20Zn–0.41Zr alloys. The corrosion resistance of the alloys after double extrusion was also studied. The results show that the microstructure of the alloys under double extrusion becomes much finer and more homogeneous than those under once extrusion. The yield strength, ultimate tensile strength and elongation of the alloys under double extrusion are over 270 MPa, 300 MPa and 32%, respectively, indicating that outstanding mechanical properties of Mg–Nd–Zn–Zr alloy can be obtained by double extrusion. The results of immersion experiment and electrochemical measurements in SBF show that the corrosion resistance of Alloy 1 and Alloy 2 under double extrusion was increased by 7% and 8% respectively compared with those under just once extrusion.

  7. Improvement of mechanical properties and corrosion resistance of biodegradable Mg-Nd-Zn-Zr alloys by double extrusion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaobo, E-mail: xbxbzhang2003@163.com [School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing, 211167 (China); Wang, Zhangzhong [School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing, 211167 (China); Yuan, Guangyin [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai, 200240 (China); Xue, Yajun [School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing, 211167 (China)

    2012-08-01

    Highlights: Black-Right-Pointing-Pointer Microstructure of Mg-Nd-Zn-Zr alloys was refined and homogenized by double extrusion process. Black-Right-Pointing-Pointer The mechanical properties of the alloys were significantly enhanced by double extrusion. Black-Right-Pointing-Pointer The biocorrosion resistance of the alloys was improved by double extrusion. - Abstract: Mg-Nd-Zn-Zr alloy is a novel and promising biodegradable magnesium alloy due to good biocompatibility, desired uniform corrosion mode and outstanding corrosion resistance in simulated body fluid (SBF). However, the corrosion resistance and mechanical properties should be improved to meet the requirement of the biodegradable implants, such as plates, screws and cardiovascular stents. In the present study, double extrusion process was adopted to refine microstructure and improve mechanical properties of Mg-2.25Nd-0.11Zn-0.43Zr and Mg-2.70Nd-0.20Zn-0.41Zr alloys. The corrosion resistance of the alloys after double extrusion was also studied. The results show that the microstructure of the alloys under double extrusion becomes much finer and more homogeneous than those under once extrusion. The yield strength, ultimate tensile strength and elongation of the alloys under double extrusion are over 270 MPa, 300 MPa and 32%, respectively, indicating that outstanding mechanical properties of Mg-Nd-Zn-Zr alloy can be obtained by double extrusion. The results of immersion experiment and electrochemical measurements in SBF show that the corrosion resistance of Alloy 1 and Alloy 2 under double extrusion was increased by 7% and 8% respectively compared with those under just once extrusion.

  8. 玉米蛋白粉吸水性挤压膨化工艺的优化%Process Optimization for Extrusion of Corn Gluten Meal

    Institute of Scientific and Technical Information of China (English)

    王丽艳; 郭树国

    2013-01-01

    To explore the optimum process of corn gluten meal,the influence of moisture content of corn gluten meal,screw rotation speed and extruding cylinder temperature on WAI (Water-Absorption Index)of corn gluten meal were studied with rotational composite design of quadratic regression.The results indicated that moisture content of corn gluten meal had great effect on experiment index;the major factors in order of importance were moisture content of corn gluten meal, screw rotation speed and extruding cylinder temperature.The optimized combination of factors were moisture content of corn gluten meal 43%,screw rotation speed 243 r/min and extruding cylinder temperature 157℃,under the optimum conditions WAI was 7.50.%为获得吸水性较高的玉米蛋白粉,采用二次通用旋转组合设计试验方法考察了玉米蛋白粉含水率、螺杆转速和机筒温度对玉米蛋白粉吸水性的影响,并对其加工工艺进行了优化。结果表明:影响玉米蛋白粉吸水性的主要因素是玉米蛋白粉含水量,其次是螺杆转速和机筒温度。在玉米蛋白粉含水率为43%、转速为243 r/min、机筒温度为157℃的挤压条件下,玉米蛋白粉的吸水性最高,吸水指数为7.50。

  9. A finite element model of ultrasonic extrusion

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, M [Department of Mechanical Engineering, University of Glasgow, G12 8QQ (United Kingdom); Daud, Y, E-mail: m.lucas@mech.gla.ac.u [College of Science and Technology, UTM City Campus, Kuala Lumpur (Malaysia)

    2009-08-01

    Since the 1950's researchers have carried out investigations into the effects of applying ultrasonic excitation to metals undergoing elastic and plastic deformation. Experiments have been conducted where ultrasonic excitation is superimposed in complex metalworking operations such as wire drawing and extrusion, to identify the benefits of ultrasonic vibrations. This study presents a finite element analysis of ultrasonic excitation applied to the extrusion of a cylindrical aluminium bar. The effects of friction on the extrusion load are reported for the two excitation configurations of radially and axially applied ultrasonic vibrations and the results are compared with experimental data reported in the literature.

  10. Application of Electrostatic Extrusion – Flavour Encapsulation and Controlled Release

    OpenAIRE

    Manojlovic, Verica; Rajic, Nevenka; Djonlagic, Jasna; Obradovic, Bojana; Nedovic, Viktor; Bugarski, Branko

    2008-01-01

    The subject of this study was the development of flavour alginate formulations aimed for thermally processed foods. Ethyl vanilline was used as the model flavour compound. Electrostatic extrusion was applied for the encapsulation of ethyl vanilline in alginate gel microbeads. The obtained microbeads with approx. 10 % w/w of ethyl vanilline encapsulated in about 2 % w/w alginate were uniformly sized spheres of about 450 μm. Chemical characterization by H-NMR spectroscopy revealed that the algi...

  11. COUPLED NUMERICAL SIMULATION OF STEEL FLOW AND SOLIDIFICATION IN SOFT-CONTACT BILLET MOLD

    Institute of Scientific and Technical Information of China (English)

    A.Y. Deng; J.C. He

    2002-01-01

    A coupled model including electromagnetic field, fluid dynamic, heat transfer and so-lidification, is developed and applied to the numerical simulation of steel flow andsolidification in a 100mm× 100mm soft-contact mold. In this study, the 3D finite dif-ference method and n, on-staggered grid system for fluid flow with body fitted coordinatewere employed. Numerical results show that the electromagnetic force mainly affectsthe steel flow at upper part of mold, especially in the vicinity of meniscus. There existupward flows covering the surfaces of the billet due to the concentration of electro-magnetic force on the upper part of the billet. This flows join together and form adownward flow near the SEN, so a distinct circulating flow zone is formed at upperpart of mold. After applying electromagnetic force, the steel velocity is improved andthe temperature is raised. The strong stirring of electromagnetic force on liquid steelmakes the kinetic energy on free surface increase. It is clearly seen that the solidifi-cation start point shifts downward in soft contact mold. As a result, the initial shellthickness gets thin and the initial solidification shell length is shortened.

  12. Correlation between local ultrasonic properties and grain size within jet-engine nickel alloy billets

    International Nuclear Information System (INIS)

    Ultrasonic velocity, attenuation, and back-scattered grain noise have been measured in rectangular coupons cut from representative 10''-diameter billets of IN718 and Waspaloy. Ultrasonic attenuation and backscattered noise were found to vary significantly with position within a billet, principally with radial depth. However, at a given measurement site there was little dependence of ultrasonic properties on inspection direction, suggesting an approximately equiaxed, untextured microstructure. Subsequent metallographic examinations revealed equiaxed grain structures in which the average grain diameter varied with position, tending to be largest at sites with large attenuations and large grain noise levels. The manner in which attenuation or backscattered-noise capacity (FOM) grows with increasing average grain diameter is similar to that expected for Pure-Ni microstructures. However, the rise rates are somewhat smaller for the jet-engine alloys, likely due to differences between the single-crystal elastic constants of the alloys and those of pure Ni. This paper reviews the methods used for ultrasonic measurements and metallographic analyses, and summarizes the interrelationships between attenuation, backscattered noise capacity and average grain diameter

  13. Prediction of Hot Tear Formation in Vertical DC Casting of Aluminum Billets Using a Granular Approach

    Science.gov (United States)

    Sistaninia, M.; Drezet, J.-M.; Phillion, A. B.; Rappaz, M.

    2013-09-01

    A coupled hydromechanical granular model aimed at predicting hot tear formation and stress-strain behavior in metallic alloys during solidification is applied to the semicontinuous direct chill casting of aluminum alloy round billets. This granular model consists of four separate three-dimensional (3D) modules: (I) a solidification module that is used for generating the solid-liquid geometry at a given solid fraction, (II) a fluid flow module that is used to calculate the solidification shrinkage and deformation-induced pressure drop within the intergranular liquid, (III) a semisolid deformation module that is based on a combined finite element/discrete element method and simulates the rheological behavior of the granular structure, and (IV) a failure module that simulates crack initiation and propagation. To investigate hot tearing, the granular model has been applied to a representative volume within the direct chill cast billet that is located at the bottom of the liquid sump, and it reveals that semisolid deformations imposed on the mushy zone open the liquid channels due to localization of the deformation at grains boundaries. At a low casting speed, only individual pores are able to form in the widest channels because liquid feeding remains efficient. However, as the casting speed increases, the flow of liquid required to compensate for solidification shrinkage also increases and as a result the pores propagate and coalesce to form a centerline crack.

  14. Original position statistic distribution analysis study of low alloy steel continuous casting billet

    Institute of Scientific and Technical Information of China (English)

    WANG Haizhou; ZHAO Pei; CHEN Jiwen; LI Meiling; YANG Zhijun; WU Chao

    2005-01-01

    The homogeneity of low alloy steels continuous casting billet obtained under different technological conditions has been investigated by original position statistic distribution analysis technique. On the basis of systematic analysis of ten thousands primary optical signals at the corresponding original positions, the quantitative statistic distribution information of each element was obtained. The biggest degrees of segregation of low alloy steel continuous casting billet were calculated accurately according to the quantitative distribution maps of the contents. It was suggested that the weight ratio in a certain content range was used to judge the homogeneity of the materials, and the two models -- the total weight ratio of contents (the degree of statistic homogeneity, H) within the permissive content range (C0±R) and the median value confidence extension ratio (the degree of statistic segregation, S) at 95% of confidence limit of weight ratio -- were put forward. The two models reflect the composition and state distribution regularity of the metal materials in a large region. The difference between the sample with high columnar crystal and the sample with high equiaxed crystal has been studied by using the two models.

  15. Optimization of microstructure during deformation processing using control theory principles

    Energy Technology Data Exchange (ETDEWEB)

    Venugopal, S.; Medina, E.A.; Malas, J.C. III; Medeiros, S.; Frazier, W.G.; Mullins, W.M. [Wright Lab., Wright Patterson AFB, OH (United States). Materials Directorate; Srinivasan, R. [Wright State Univ., Dayton, OH (United States). Dept. of Mechanical and Materials Engineering

    1997-02-01

    The development of optimal design and control methods for manufacturing processes is needed for effectively reducing part cost, improving part delivery schedules and producing specified part quality on a repeatable basis. A new strategy for systematically calculating near optimal control parameters for hot deformation processes for microstructural control is presented in this communication. This approach is based on modern control theory and involves developing state-space models from available material behavior and hot deformation process models. The control system design consists of two basic stages and analysis and optimization are critical in both stages. In the first stage, the kinetics of certain dynamic microstructural behavior and the intrinsic hot workability of the material are used, along with an appropriately chosen optimality criterion, to calculate optimum strain, strain-rate, and temperature trajectories for processing. A suitable process simulation model is then used in the second stage to calculate process control parameters, such as ram velocity, die profiles and billet temperature, which approximately achieve the strain, strain-rate, and temperate trajectories calculated in the first stage at selected areas of the workpiece. The validity of this approach has been demonstrated with an example on hot extrusion of steel.

  16. RESEARCH ON THE SELECTION OF FRICTION MODELS IN THE FINITE ELEMENT SIMULATION OF WARM EXTRUSION

    Institute of Scientific and Technical Information of China (English)

    X.B. Lin; H.S. Xiao; Z.L. Zhang

    2003-01-01

    During the process of finite element simulation of precision warm forging, the selec-tion of friction models has a direct effect on the precision accuracy of finite elementsimulation results. Among all the factors which influence the selection of frictionmodels, the distribution rule of normal stress at the tool-workpiece interface is a keyone. To find out the distribution rule of normal stress at the tool-workpiece inter-face, this paper has made a systematic research on three typical plastic deformationprocesses: forward extrusion, backward extrusion, and lateral extrusion by a methodof finite element simulation. Then on the base of synthesizing and correcting tradi-tional friction models, a new general friction model which is fit for warm extrusion isdeveloped at last.

  17. Effect of extrusion temperature on the physical properties of high-silicon aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    YANG Fuliang; GAN Weiping; CHEN Zhaoke

    2007-01-01

    Light-weight high-silicon aluminum alloys are used for electronic packaging in the aviation and space- flight industry. Al-30Si and Al-40Si are fabricated with air- atomization and vacuum-canning hot-extrusion process. The density, thermal conductivity, hermeticity and thermal expan- sion coefficients of the material are measured, and the relationship between extrusion temperature and properties is obtained. Experimental results show that the density of high- silicon aluminum alloys prepared with this method is as high as 99.64% of the theory density, and increases with elevating extrusion temperature. At the same time, thermal conductiv- ity varies between 104-140W/(m.K); with the extrusion temperature, thermal expansion coefficient also increases but within 13 × 10-6 (at 100℃) and hermeticity of the material is high to 10-9 order of magnitude.

  18. Extrusion-formed uranium-2. 4 wt % article with decreased linear thermal expansion and method for making the same. [Patent application

    Science.gov (United States)

    Anderson, R.C.; Jones, J.M.; Kollie, T.G.

    1982-05-24

    The present invention is directed to the fabrication of an article of uranium-2.4 wt % niobium alloy in which the linear thermal expansion in the direction transverse to the extrusion direction is less than about 0.98% between 22 and 600/sup 0/C which corresponds to a value greater than the 1.04% provided by previous extrusion operations over the same temperature range. The article with the improved thermal expansion possesses a yield strength at 0.2% offset of at least 400 MPa, an ultimate tensile strength of 1050 MPa, a compressive yield strength of at least 0.2% offset of at least 675 MPa, and an elongation of at least 25% over 25.4 mm/s. To provide this article with the improved thermal expansion, the uranium alloy billet is heated to 630/sup 0/C and extruded in the alpha phase through a die with a reduction ratio of at least 8.4:1 at a ram speed no greater than 6.8 mm/s. These critical extrusion parameters provide the article with a desired decrease in the linear thermal expansion while maintaining the selected mechanical properties without encountering crystal disruption in the article.

  19. HA/UHMWPE Nanocomposite Produced by Twin-screw Extrusion

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The HA/UHMWPE nanocomposite is compounded by twin-screw extrusion of the HA and UHMWPE powder mixture in paraffin oil and then compression molded to a sheet form. TGA measurement shows the HA weight loss after processing is about 1%-2% . FTIR spectra indicate the paraffin oil residue is trivial and UHMWPE is not oxidized. SEM reveals the HA nano particles are homogeneously dispersed by twin- screw extrusion and the inter-particle spaces are penetrated with UHMWPE fibrils by swelling treatment. HRTEM image indicates the HA particles and UHMWPE are intimately contacted by mechanical interlocking. Compared with the unfilled UHMWPE, stiffness of the composite with the HA volume fraction 0.23 was significantly enhanced to 9 times without detriment of the yield strength and the ductility.

  20. Functionalization of whey proteins by reactive supercritical fluid extrusion

    Directory of Open Access Journals (Sweden)

    Khanitta Ruttarattanamongkol

    2012-09-01

    Full Text Available Whey protein, a by-product from cheese-making, is often used in a variety of food formulations due to its unsurpassednutritional quality and inherent functional properties. However, the possibilities for the improvement and upgrading of wheyprotein utilization still need to be explored. Reactive supercritical fluid extrusion (SCFX is a novel technique that has beenrecently reported to successfully functionalize commercially available whey proteins into a product with enhanced functionalproperties. The specific goal of this review is to provide fundamental understanding of the reinforcement mechanism andprocessing of protein functionalization by reactive SCFX process. The superimposed extrusion variables and their interactionmechanism affect the physico-chemical properties of whey proteins. By understanding the structure, functional properties andprocessing relationships of such materials, the rational design criteria for novel functionalized proteins could be developedand effectively utilized in food systems.

  1. HIGH ENERGY RATE EXTRUSION OF URANIUM

    Science.gov (United States)

    Lewis, L.

    1963-07-23

    A method of extruding uranium at a high energy rate is described. Conditions during the extrusion are such that the temperature of the metal during extrusion reaches a point above the normal alpha to beta transition, but the metal nevertheless remains in the alpha phase in accordance with the Clausius- Clapeyron equation. Upon exiting from the die, the metal automatically enters the beta phase, after which the metal is permitted to cool. (AEC)

  2. Formation of chromosomal domains in interphase by loop extrusion

    Science.gov (United States)

    Fudenberg, Geoffrey

    While genomes are often considered as one-dimensional sequences, interphase chromosomes are organized in three dimensions with an essential role for regulating gene expression. Recent studies have shown that Topologically Associating Domains (TADs) are fundamental structural and functional building blocks of human interphase chromosomes. Despite observations that architectural proteins, including CTCF, demarcate and maintain the borders of TADs, the mechanisms underlying TAD formation remain unknown. Here we propose that loop extrusion underlies the formation TADs. In this process, cis-acting loop-extruding factors, likely cohesins, form progressively larger loops, but stall at TAD boundaries due to interactions with boundary proteins, including CTCF. This process dynamically forms loops of various sizes within but not between TADs. Using polymer simulations, we find that loop extrusion can produce TADs as determined by our analyses of the highest-resolution experimental data. Moreover, we find that loop extrusion can explain many diverse experimental observations, including: the preferential orientation of CTCF motifs and enrichments of architectural proteins at TAD boundaries; TAD boundary deletion experiments; and experiments with knockdown or depletion of CTCF, cohesin, and cohesin-loading factors. Together, the emerging picture from our work is that TADs are formed by rapidly associating, growing, and dissociating loops, presenting a clear framework for understanding interphase chromosomal organization.

  3. Recent Developments in Mechanochemical Materials Synthesis by Extrusion.

    Science.gov (United States)

    Crawford, Deborah E; Casaban, José

    2016-07-01

    Mechanochemical synthesis, i.e., reactions conducted by grinding solid reactants together with no or minimal solvent, has been demonstrated as an excellent technique for the formation of both organic and inorganic compounds. Mechanochemistry is viewed as an alternative approach to chemical synthesis and is not always considered when developing manufacturing processes of fine chemicals. Here, recent advances are highlighted regarding mechanochemical synthesis, by utilizing a well-developed continuous technique - extrusion, and the advantages it offers to further support its use in the manufacturing of these chemicals. To put this work into context, it is shown how extrusion plays a vital role for manufacturing in the food, polymer, and pharmaceutical industries, and how the research carried out by these respective industrialists provides great insight and understanding of the technique, with the results being applicable in the chemical industry. The synthesis of metal-organic frameworks (MOFs) is highlighted herein as an excellent example showcasing the advantages that extrusion provides to the manufacture of these materials, one advantage being the exceptional space time yields (STYs) reported for these processes, at three orders of magnitude greater than conventional (solvothermal) synthesis. PMID:26932541

  4. Extrusion of metal oxide superconducting wire, tube or ribbon

    Science.gov (United States)

    Dusek, Joseph T.

    1993-10-05

    A process for extruding a superconducting metal oxide composition YBa.sub.2 Cu.sub.3 O.sub.7-x provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6-85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87-355 mil has also been produced. Flat ribbons have been produced in the range of 10-125 mil thick by 100-500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.

  5. Hot-melt extrusion technology and pharmaceutical application.

    Science.gov (United States)

    Wilson, Matthew; Williams, Marcia A; Jones, David S; Andrews, Gavin P

    2012-06-01

    The use of hot-melt extrusion (HME) within the pharmaceutical industry is steadily increasing, due to its proven ability to efficiently manufacture novel products. The process has been utilized readily in the plastics industry for over a century and has been used to manufacture medical devices for several decades. The development of novel drugs with poor solubility and bioavailability brought the application of HME into the realm of drug-delivery systems. This has specifically been shown in the development of drug-delivery systems of both solid dosage forms and transdermal patches. HME involves the application of heat, pressure and agitation through an extrusion channel to mix materials together, and subsequently forcing them out through a die. Twin-screw extruders are most popular in solid dosage form development as it imparts both dispersive and distributive mixing. It blends materials while also imparting high shear to break-up particles and disperse them. HME extrusion has been shown to molecularly disperse poorly soluble drugs in a polymer carrier, increasing dissolution rates and bioavailability. The most common difficulty encountered in producing such dispersions is stabilization of amorphous drugs, which prevents them from recrystallization during storage. Pharmaceutical industrial suppliers, of both materials and equipment, have increased their development of equipment and chemicals for specific use with HME. Clearly, HME has been identified as an important and significant process to further enhance drug solubility and solid-dispersion production. PMID:22838073

  6. Application of Numerical Simulation on the Manufacturing Process Qualification of Nuclear Power Plant Steam Generator Tube-sheet

    Directory of Open Access Journals (Sweden)

    Zhang Shao Jun

    2016-01-01

    Full Text Available Nuclear power plant key parts-steam generator (SG tube sheet forging operate in harsh environment, so it has high requirements for internal quality. According to RCC-M specification requirements (take CPR1000 reactor type for example, the manufacturer should carry out workshop qualification and part process qualification before delivery product manufacturing. It is commonly used that centre compaction process and conical plate upsetting process regard as two kinds of large forging upsetting ways. The numerical analogue simulation has been carried out on nuclear power large tube sheet forgings using France Forge simulation software. The results show that: when the same pressure size, 3-direction compressive stress in the core of the billet always exist in the process of upsetting using centre pressing process, and the strain create in the central of the billet, but stagnant zone exist on the bottom and end plane; tensile stress in the core of the billet always exist in the process of upsetting using conical plate upsetting process, it will force the billet that contact with conical plate to deform, so eliminate stagnant zone, but effective deformation don’t produce in the central of the billet. The conical plate continue press for conical plate upsetting process, tensile stress in the core of the billet disappear, and then gradually change into pressure stress, then tensile stress is generated at the bottom, finally tensile stress disappear and 3-direction compressive stress exist in the core of the billet.

  7. Modelling the influence of the gas to melt ratio on the fraction solid of the surface in spray formed billets

    DEFF Research Database (Denmark)

    Hattel, Jesper Henri; Pryds, Nini

    2006-01-01

    atomisation stage taking thermal coupling into consideration and the deposition of the droplets at the surface of the billet taking geometrical aspects such as shading into account. The coupling between these two models is accomplished by ensuring that the total droplet size distribution of the spray is the...

  8. Effect of the heat treatment prior to extrusion on the direct hot-extrusion of aluminium powder compacts

    Energy Technology Data Exchange (ETDEWEB)

    Zubizarreta, C.; Gimenez, S.; Martin, J.M. [CEIT and TECNUN, Po Manuel de Lardizabal 15, 20018 San Sebastian (Spain); Iturriza, I. [CEIT and TECNUN, Po Manuel de Lardizabal 15, 20018 San Sebastian (Spain)], E-mail: iiturriza@ceit.es

    2009-01-07

    Powder compacts from a premixed commercial aluminium powder Al-4.5Cu-0.5Mg-0.2Si (wt%) grade have been densified by direct hot-extrusion. The effect of the heat treatment prior to extrusion on the microstructural evolution of the extruded compacts has been investigated by means of light optical microscopy (LOM), scanning electron microscopy (SEM), and electron backscattered diffraction (EBSD). The interdiffusion of chemical species has demonstrated to have a pronounced influence on the hardening-softening mechanisms taking place during the thermomechanical process. Moreover, the degree of strain attained at different regions (centre and periphery) of the specimens also affects significantly to the mechanisms involved. Grain refinement, intermetallic precipitation, dynamic recovery, and recrystallization have been identified.

  9. Lateral extrusion of tailor welded aluminum alloy pipes with a lost core of low temperature melting alloy

    OpenAIRE

    Ohashi, T.; Liu, G.

    2009-01-01

    Purpose: In this paper, the authors employ tailor welded aluminum alloy pipes for lateral extrusion process with a lost core to perform a hollow light-weight-part.Design/methodology/approach: The pipe is welded longitudinally by YAG-laser. “The lateral extrusion process with a lost core (LELC)” consists of lateral extrusion of pipes with a soluble solid core, called the “lost core”, which serves as a plastic mandrel. The process proceeds as follows. First, the pipe cavity is filled with the l...

  10. ANÁLISIS BACTERIOLÓGICO DE BILLETES CIRCULANTES EN LA UNIVERSIDAD DEL PACÍFICO PARAGUAY. 2013

    Directory of Open Access Journals (Sweden)

    Nathalia Aguilera –Benítez

    2016-07-01

    Full Text Available Introducción: Los billetes de algodón poseen una estructura porosa que le permite alojar diferentes tipos de detritus y que posibilitaría la colonización microbiana de dicho papel. Objetivos: Describir la presencia y tipo de contaminación bacteriana en dos variedades de billetes circulantes en Paraguay, en el año 2013. Materiales y métodos: Se recolectaron 50 billetes de cinco mil guaraníes (25 de polímero y 25 de algodón proveídos por estudiantes mediante un muestreo por conveniencia. El análisis consistió en el aislamiento bacteriológico presente en superficies de billetes. Fueron sumergidos e incubados a 37° durante 24 hs. en caldo de infusión cerebro corazón (BHI y posteriormente sembrados en placas de agar Sangre y MacConkey. Finalmente se procedió a la tipificación de los aislamientos obtenidos. Resultados: El 74%(37/50 de los billetes evaluados presentaron contaminación bacteriana; las frecuencias fueron del 100%(25/25 y 48%(12/25 respectivamente para los de algo­dón y polímero. En el primer grupo se aislaron con mayor frecuencia bacterias de la familia Enterobacteriaceae en el 61%(17/28 y del género Staphylococcus spp. en el 39%(11/28. En el segundo grupo se aislaron Staphylococcus spp. en el 44%(11/25 y Escherichia coli en 4 %(1/25. Conclusión: El estudio ha permitido evidenciar que los billetes contribuyen a la proliferación y transmisión de microorganismos al ser humano, pudiendo causar daños a la salud según estado inmunológico de la persona. Se evidenció que billetes de algodón presentan mayor frecuencia y variabilidad de contaminación por bacterias. Palabras Clave: Microbiología, Dinero, Bacterias, aislamiento & purificación.

  11. Concept Feasibility Report for Using Co-Extrusion to Bond Metals to Complex Shapes of U-10Mo

    Energy Technology Data Exchange (ETDEWEB)

    Lavender, Curt A.; Paxton, Dean M.; Smith, Mark T.; Soulami, Ayoub; Joshi, Vineet V.; Burkes, Douglas

    2013-12-30

    In support of the Convert Program of the U.S. Department of Energy’s National Nuclear Security Administration (DOE/NNSA) Global Threat Reduction Initiative (GTRI), Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum (U-10Mo) alloy plate fuel for the U.S. high-performance research reactors (USHPRR). This report documents the results of PNNL’s efforts to develop the extrusion process for this concept. The approach to the development of a co-extruded complex-shaped fuel has been described and an extrusion of DU-10Mo was made. The initial findings suggest that given the extrusion forces required for processing U-10Mo, the co-extrusion process can meet the production demands of the USHPRR fuel and may be a viable production method. The development activity is in the early stages and has just begun to identify technical challenges to address details such as dimensional tolerances and shape control. New extrusion dies and roll groove profiles have been developed and will be assessed by extrusion and rolling of U-10Mo during the next fiscal year. Progress on the development and demonstration of the co-extrusion process for flat and shaped fuel is reported in this document

  12. 轧钢加热炉钢坯"黑匣子"测温方法%Black box temperature measurement for billet in steel heating furnace

    Institute of Scientific and Technical Information of China (English)

    钱惠国; 高超

    2015-01-01

    提出了钢坯加热质量要求的测点布置方法,并对PhoenixTM黑匣子测试系统作了简要介绍,同时指出采用与该钢种相近的金属粉末(或铁粉替代)灌注测试孔并作压实处理,可提高热电偶的测温精度,以及使用502胶水将热电偶牢牢固定在钢坯上,以防止钢坯测试点热偶在辊道上移动时脱位. 通过对轧钢加热炉的应用试验,可全面获得加热炉的炉气温度及钢坯各方向的测点温度值,供用户改进加热制度,既保证钢坯加热工艺,又能实现节能减排.%A way of measuring point arrangement for billet heating requirements was put forward .The PhoenixTM black box system was briefly introduced .It is pointed out that filling and ramming the instrument connection with metal powder ( or iron powder ) can improve the measurement accuracy of thermocouple and fixing the thermocouple to the billet with No .502 glue can avoid dislocation .Acquiring the furnace gas temperature and station temperature can provide data support to improve the way of heating and ensure the quality of heating process as well as energy conservation .

  13. Effect of extrusion on corrosion behavior and corrosion mechanism of Mg-Y alloy

    Institute of Scientific and Technical Information of China (English)

    XU Hong; ZHANG Xin; ZHANG Kui; SHI Yang; REN Jiping

    2016-01-01

    The influences of the hot extrusion process on the microstructure, corrosion behavior and corrosion mechanism for Mg-Y magnesium alloy were studied by means of the microstructure observation, weight loss test, electrochemical test and corrosion mor-phology test. The results showed that with increasing of the extrusion ratio, the shear flow line on the vertical section of the extruded alloy increased, the shear bands parallel lines became more clearly visible, and a large number of fine equiaxed grains distributed in parallel with the flow lines. The open circuit potential had a certain degree of improvement after extrusion, the open circuit potential increased with increment of extrusion ratio, and the corrosion potential of the vertical section was higher than that of the same alloy in the same compression ratio. The shift rate of the corrosion potential relatively became larger with increasing of the extrusion ratio, and the cathode corrosion current corresponding to the branch migration shifted to the positive direction. The high frequency capaci-tive arc increased with increment of the extrusion ratio, and the radius of capacitive arc of the vertical section was slightly larger than that of the transverse section. The corrosion morphologies of Mg-0.25Y alloy were uniform corrosion, and the corrosion morpholo-gies of Mg-(2.5, 5, 8 and 15) were the pitting corrosion and the small range, deep depth localized corrosion.

  14. Microstructure and highly enhanced mechanical properties of fine-grained tungsten heavy alloy after one-pass rapid hot extrusion

    International Nuclear Information System (INIS)

    Research highlights: → The strength of fine-grained WHAs is as high as 1570 MPa after rapid hot extrusion. → Plastic deformation of fine-grained WHAs during rapid hot extrusion is uniform. → Slight dynamic recovery-recrystallization process occurred during hot extrusion. → Fine grains and reserved numerous dislocations contribute to the high strength. - Abstract: One-pass rapid hot extrusion of fine-grained 93W-4.9Ni-2.1Fe-0.03Y (wt.%) alloy with an average grain size of ∼10 μm was performed at 1150 deg. C with an extrusion speed of ∼100 mm/s and an extrusion ratio of ∼3.33:1. Microstructure and mechanical properties of the as-extruded alloy were investigated. The results show that the tungsten particles of the as-extruded alloy are severely elongated along the extrusion direction and the aspect ratios of these elongated particles are 5-8. Three crystallographic textures {0 0 1}, {1 1 1} and {1 1 0} arose after rapid hot extrusion and the total volume fraction of these texture components was approximately 30%. Many lath-shaped subgrains with a small misorientation and low density dislocations could be observed in tungsten phase and γ-(Ni, Fe) phase respectively. These microstructure characteristics indicate that slight dynamic recovery-recrystallization process occurred during rapid hot extrusion. In contrast to as-sintered alloy, the as-extruded alloy possessed much higher ultimate tensile strength and hardness (HRC) but a relatively lower ductility (1570 MPa vs. 995 MPa; HRC48 vs. HRC29 and 6.5% vs. 24%). In addition, the fracture morphology shows that the predominant failure mode for the as-extruded alloy is cleavage failure of the tungsten particles, while the ductile rupture of the γ-(Ni, Fe) phase that can be frequently observed in the as-sintered alloy nearly disappeared after rapid hot extrusion.

  15. The Effect of Cooling Rate after Homogenization on the Microstructure and Properties of 2017a Alloy Billets for Extrusion with Solution Heat Treatment on the Press

    Directory of Open Access Journals (Sweden)

    Woźnicki A.

    2016-09-01

    Full Text Available The influence of cooling rate after homogenization on the 2017A alloy microstructure was analysed. The capability of the θ (Al2Cu particles, precipitated during various homogenization coolings, for rapid dissolution was estimated. For this purpose, the DSC test was used to determine the effect of the cooling rate after homogenization on the course of melting during a rapid heating. Moreover, the samples after solution heat treatment (with short time annealing and ageing, were subjected to the microstructure investigations and the microhardness of grains interiors measurements. It was found that cooling after homogenization at 160 °C/h is sufficient for precipitation of fine θ phase particles, which dissolve during the subsequent rapid heating. The cooling at 40 °C/h, causes the precipitation of θ phase in the form of large particles, incapable of further fast dissolution.

  16. System to control large billet rolling facilities; Ogata biretto atsuen setsubi seigyo system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-10

    A system to control large billet rolling facilities was delivered. This system consists of a GTO inverter and a cycloconverter for a large rolling machine, IGBT inverters for auxiliary machines, programmable controllers (ICS-2500), man-machine interfaces (PMS-2500), and a computer for control (DC/90). It has realized fully automatic operation based on the operation supporting data. Its main functions are as follows: (1) fully automatic control of a shifting reverse rolling machine, (2) automatic size control to control rolling sizes of products by using recorded data of sizes and temperatures, (3) automatic heating control to heat materials to targeted temperatures during rolling, (4) automatic calculation of cutting patterns of materials to be rolled, and fully automatic cutting control, and (5) fully automatic control of transportation of materials to a targeted position. (NEDO)

  17. Meniscus Behavior in Electromagnetic Soft-Contact Continuous Casting Round Billet Mold

    Institute of Scientific and Technical Information of China (English)

    DENG An-yuan; WANG En-gang; HE Ji-cheng

    2006-01-01

    Using molten Pb-Sn-Bi alloy, the meniscus shape under high frequency magnetic field of φ100 mm round billet caster was investigated. The effect of some parameters on meniscus shape was studied. The results show that for a mold with 12 segments, the meniscus shape is relatively stable. With increasing power input, the meniscus height increases with intensification of fluctuation. For the given caster, the reasonable power input is about 70 kW. The coil should be near to the top of mold and/or the initial meniscus should be near to the center of the coil. The lower the frequency, the higher is the meniscus height. With increasing frequency, the free surface is more flattened and meniscus becomes more stable. In practice, the power input should be increased simultaneously with frequency. The optimal frequency is about 20 kHz.

  18. Effects of calculation approaches for thermal conductivity on the simulation accuracy of billet continuous casting

    Institute of Scientific and Technical Information of China (English)

    Zun Peng; Yan-ping Bao; Ya-nan Chen; Li-kang Yang; Cao Xie; Feng Zhang

    2014-01-01

    An unsteady, two-dimensional, explicitly solved finite difference heat transfer model of a billet caster was presented to clarify the influence of the thermal conductivity of steel on model accuracy. Different approaches were utilized for calculating the thermal conductivity of solid, mushy and liquid steels. Model results predicted by these approaches were compared, and the advantages of advocated approaches were discussed. It is found that the approach for calculating the thermal conductivity of solid steel notably influences model predictions. Convection effects of liquid steel should be considered properly while calculating the thermal conductivity of mushy steel. Different values of the effective thermal conductivity of liquid steel adopted could partly be explained by the fact that different models adopted dissimilar ap-proaches for calculating the thermal conductivity of solid and mushy steels.

  19. Mitotic chromosome compaction via active loop extrusion

    Science.gov (United States)

    Goloborodko, Anton; Imakaev, Maxim; Marko, John; Mirny, Leonid; MIT-Northwestern Team

    During cell division, two copies of each chromosome are segregated from each other and compacted more than hundred-fold into the canonical X-shaped structures. According to earlier microscopic observations and the recent Hi-C study, chromosomes are compacted into arrays of consecutive loops of ~100 kilobases. Mechanisms that lead to formation of such loop arrays are largely unknown. Here we propose that, during cell division, chromosomes can be compacted by enzymes that extrude loops on chromatin fibers. First, we use computer simulations and analytical modeling to show that a system of loop-extruding enzymes on a chromatin fiber self-organizes into an array of consecutive dynamic loops. Second, we model the process of loop extrusion in 3D and show that, coupled with the topo II strand-passing activity, it leads to robust compaction and segregation of sister chromatids. This mechanism of chromosomal condensation and segregation does not require additional proteins or specific DNA markup and is robust against variations in the number and properties of such loop extruding enzymes. Work at NU was supported by the NSF through Grants DMR-1206868 and MCB-1022117, and by the NIH through Grants GM105847 and CA193419. Work at MIT was supported by the NIH through Grants GM114190 R01HG003143.

  20. Control of material flow in a combined backward can - forward rod extrusion

    DEFF Research Database (Denmark)

    Kuzman, K; Pfeifer, E; Bay, Niels;

    1996-01-01

    The paper deals with an analysis of an extrusion process with a divided material flow. As we are forced to seek for optimal technological solutions with short testing times and low risks and costs, a reliable process evaluation is of the greatest importance. The paper discusses the influences...... of tool geometry, friction and lubrication as well as workpiece properties on balanced material flow in a combined extrusion process. The FEM analysis applying the DEFORM code has been used in order to predict the process parameters and to estimate its stability. The subsequent experimental verification...

  1. Investigations on the influence of the shape factor and friction in compression processes of cylindrical billets of AA 6082-T6 aluminum alloy by numerical and experimental techniques; Investigaciones sobre la influencia del factor de forma y del rozamiento en procesos de compresion de piezas cilindricas de aleacion de aluminio AA 6082-T6 mediante tecnicas numericas y experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Marin, M. M.; Camacho, A. M.; Bernal, C.; Sebastian, M. A.

    2013-09-01

    The material characterization under similar load conditions to those applied during manufacturing is important in order to analyse Bulk Forming Compression Processes from a more realistic point of view. Open die forging of AA 6082-T6 aluminum alloy has been analysed by using experimental techniques and Finite Elements Method (FEM). The influence of the work piece geometry on the effects that friction produces in typical process variables such as applied forces, contact pressures and stresses and strains in work pieces has been analysed by FEM simulation. It has been shown that higher shape factors of the initial work piece geometry are recommended in such a way that friction effect is minimised. These results are interesting in order to decrease the required energy of the process and the tool wear, and could be used in further analysis of stamping processes. (Author)

  2. Research on continuous variable cross-section direct extrusion (CVCDE)%连续变截面直接挤压成形技术研究

    Institute of Scientific and Technical Information of China (English)

    李峰; 林俊峰; 张鑫龙; 潘强荣

    2012-01-01

    实现晶粒细化的传统塑性加工工艺所需工序多且要求较高,为了解决这些问题,本文提出了一种能够实现金属材料制备及成形一体化的挤压成形新工艺——连续变截面直接挤压成形技术,对不同工艺条件的连续变截面挤压成形过程的数值模拟研究表明:当模角由90°增大至140°时,塑性区范围明显扩大,金属流动均匀性随之提高;模口处轴向拉应力数值减小了20%,降低了表面产生开裂的可能性;模角为90°时变截面型腔处存在死区缺陷,且流线折叠倾向较严重,模角为140°时成形过程中坯料与型腔间易出现空隙,分析认为,本文条件下模角为120°的情况比较理想。%The traditional processing to obtain refined grain by plastic working needs more processes and higher standard. In order to tackle these problems, a new technology, continuous variable crosssection direct extrusion ( CVCDE), coupled the producing and forming of the metal material is provided in this article. After simulating the different processes of CVCDE,the results show that: ,when die angle increases from 90° to 140° ,the plastic zone expands obviously and the flow uniformity of metal improves, meanwhile 20% reduction of the axial ten- sile stress reduces the chance of cracking in the surface, when the die angle is 90° ,there is dead metal zone in the cavity with variable crosssection, the streamlines are tending to fold seriously. When the die angle is 140°, the gap appears easily between billet and die cavity. Based on an overall analysis,the die angle of 120° is an ideal choice.

  3. 不同蛋白质源对高蛋白质水产饲料膨化工艺参数和加工质量的影响%Effects of Different Protein Sources on Extrusion Processing Parameters and Processing Quality for High Protein Aquatic Feed

    Institute of Scientific and Technical Information of China (English)

    梁晓芳; 李军国; 薛敏; 王嘉; 吴秀峰; 郑银桦; 韩芳; 秦玉昌

    2016-01-01

    In this study, we determined the effects of fish meal ( FM) , cottonseed protein concentrate ( CPC) and fermented soybean meal ( FSM) formulated as sole or combined protein sources in aquatic feed on the ex⁃trusion processing parameters and processing quality. Extrusion processing was conducted by a twin⁃screw ex⁃truder with steam heating and pre⁃conditioning system. FM diet was set as control diet, CPC and FSM were sole or combined used to replace 47% or 100% of FM, and then, seven diets with 45.45% to 48.55% crude protein and 18.11 to 20.33 MJ/kg gross energy were formulated and named as FM, FM×CPC, FM×FSM, CPC, FM×CPC×FSM, FSM and CPC×FSM, respectively. The results showed that the reduction of extrusion temperature and increase of screw speed and energy consumption were caused after the FM was replaced by plant proteins. With the plant protein proportion increasing, the extrusion temperature was reduced, and there was a significant negative correlation between them ( R2=0.926 2) . Processing quality parameters except dura⁃ble index of extrusion feed were significantly affected by different protein sources. The bulk density and stabili⁃ty in water in FM group were significantly higher than those in other group ( P<0.05) . On the contrary, with the increase of plant protein proportion, hardness and expansion degree of extrusion feed were increased. More⁃over, the radial expansion degree in CPC group was significantly higher than that in other groups ( P< 0.05) , and there was a significant positive correlation between the supplementation of fermented soybean meal and hardness of extrusion feed (R2=0.978 1). In conclusion, both FSM and CPC can significantly increase feed radial expansion and energy consumption compared with FM. Moreover, the bulk density of CPC is significant⁃ly lower than that of FSM and FM, which is beneficial to the production of floating feed, but not good to the production of sinking feed.%

  4. 基于响应面法的直齿轮冷挤压工艺多目标优化%Multi-objective optimization of cold extrusion process for planetary spur gear based on RSM

    Institute of Scientific and Technical Information of China (English)

    夏玉峰; 叶彩红; 王力; 任莉

    2016-01-01

    针对某型大模数行星直齿轮在精锻成形工艺中成形载荷大、齿形塌角大及弹性回复影响齿形精度等问题,提出一种新型约束分流正冷挤压工艺.以降低成形载荷、减小轴向塌角长度及取得弹性回复量较小的齿轮为优化目标,以凹模入模角、毛坯直径系数、摩擦系数和模具挤压速度为优化变量,借助正交实验设计与Design‐Expert V8软件进行响应面拟合建模分析,得到成形载荷及塌角长度的二阶响应面模型和弹性回复的线性模型,同时借助该软件进行多目标优化,得到最佳工艺参数组合,即入模角为67°,直径系数为1.15,摩擦系数为0.06,模具下压速度为52mm/s.有限元模拟和生产实践结果表明:优化后的工艺参数组合能生产得到弹性回复较小、表面质量好的行星直齿轮冷挤压件,并能有效减小塌角、降低成形载荷.%A constraint shunt cold extrusion process was put forward to solve the issues that too large forming load ,too‐large collapse angle and tooth profile accuracy affected by the elastic recovery oc‐curred during precision forging process of big modulus planetary spur gear . T he optimization goals were to reduce the forming load and the collapse angle axial length and acquire small elastic recovery for gear .The mould angle ,blank diameter coefficient ,friction coefficient and deformation speed were chosen as the optimization variables .In addition ,orthogonal design and Design‐Expert V8 software were used to establish the response surface model (RSM ) .And a linear response surface model and two quadratic response surface models were obtained .Meanwhile ,mould angle is 67° ,blank diameter coefficient is 1 .15 ,friction coefficient is 0 .06 and deformation speed is 52 mm/s were combined as the best parameters by using the Design‐Expert V8 software .At last ,the numerical simulation and pro‐duction practice show that the

  5. Modeling of severe deformation and mechanical properties in Mg-3A1-1Zn alloy through asymmetric hot-extrusion

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    One-pass asymmetric hot extrusion performed at 673 K was applied to fabricate an AZ31 magnesium alloy sheet.Finite element method(FEM)was used to model the process of asymmetric hot-extrusion.Simulation results indicate that strain rate gradient througa the thickness introduced a grain size gradient along the thickness direction and shear deformation during the asymmetric hot-extrusion results in weakened and tilted(0002)basal texture.The asymmetric hot extrusion effectively weakens the basal texture and improves the ductility,at room temperature.

  6. Prediction of extrusion die wear by use of an artificial neural network

    International Nuclear Information System (INIS)

    In its vision of designing a technology, the process of optimisation of a material extrusion is an on-line process. The tool life is an important factor in selecting the objective function that represents the cost of the extruded product. This work is intended to realise the prediction of die wear evolution within the extrusion process, based on information obtained from numerical modelling. In order to reduce the number of experiments and to realise a flexible process of designing the necessary tools for an extrusion process, finite element (FE) modelling was used to determine designing space against the shape of the extruded product, the work conditions, the material and wear conditions. The information generated using FE was then used to train a neural network using backpropagation algorithm. Parameters considered in constructing neural networks include error tolerance, the factor of estimation of the 'best solution', the number of training cycles and the number of hidden layers. A general formula of calculus applicable in any extrusion process can be determined by establishing a relation between the stress state obtained within the extrusion process, deformation speed and friction on one hand, and wear on the other hand. The (1/W) parameter, where W is the tool wear in the active zone of the extrusion die, is a measure taken into account in calculating the die life as written in (1); this is the reason why it is important to make prediction of W value for geometries used in designing process or to optimise the die shape in order to reduce wear. (author)

  7. Effect of extrusion parameters on production process and expansion ratio of reformed rice%挤压加工参数对重组米生产过程及产品膨胀度的影响

    Institute of Scientific and Technical Information of China (English)

    庄海宁; 冯涛; 金征宇; 谢正军; 徐学明; 高明; 柏玉香

    2011-01-01

    为了考察重组米生产过程中挤压加工变量对几种系统参数与产品膨胀度的影响,试验以杂交籼米(9718品种)为原料,利用响应面模型,以螺杆转速、进料速度、进料含水率以及末端机简温度为输入变量,以挤压系统参数(物料温度、模头压强、扭矩、比机械能和产品含水率)和重组米膨胀度为响应变量,探索在重组米生产过程中加工变量与系统参数及产品膨胀度的关系.结果表明,压强、比机械能和产品膨胀度都受到4个挤压变量的显著影响,但是物料温度受进料速度影响不显著,马达扭矩受末端机筒温度影响不显著,产品含水率仪受进料含水率的显著影响.比机械能与螺杆转速正相关,与进料速度、进料含水率和末端机筒温度负相关.所得二次回归模型均拟合良好,建立的挤压数学模型可应用于重组米生产,为重组米工业化生产的过程预测和产品性质预测提供参考.%Response surface methodology (RSM) was used to study the effects of screw speed, feed rate, feed moisture content, and terminal barrel temperature on several system parameters (product temperature, die pressure, motor torque, specific mechanical energy and product moisture content) and physical properties (expansion ratio) of the reformed rice made by hybrid indica rice (type 9718). Second-order polynomials were used to model the extruder responses as a function of process variables. Die pressure, specific mechanical energy and expansion ratio were affected by all four process variables, while product moisture content was only influenced by feed moisture content. Product temperature was affected by all variables except for feed rate, and motor torque was affected by all variables except for terminal barrel temperature. Specific mechanical energy increased with screw speed increment, while feed moisture and terminal barrel temperature reduced with feed rate increment. The high correlation between

  8. Study on Extrusion Technological Parametersof Brown Rice

    Institute of Scientific and Technical Information of China (English)

    ZhuYongyi; ZhouXianqing; LingLizhong

    2001-01-01

    Abstract: Extrusion is an efficient measure to improve the texture and physic-chemical properties of brown rice. The polynomial degree two model of extrusiontechnological parameters and gelatinized degree, water absorption index, water solubleindex and moisture content of extruded matter was obtained by methods of single factorand response surface methodology, R2=0.9649, 0.8745, 0.9079, 0.8677. The optimaltechnoiogica! parameters of brown rice extrusion were figured out as follows:moisturecontent of brown rice, 11.42%, speed of screw, 30rpm, feeding speed, and 20rpm.

  9. Microstructural and mechanical characterisation of 7075 aluminium alloy consolidated from a premixed powder by cold compaction and hot extrusion

    OpenAIRE

    Jabbari Taleghani, M. A.; Ruiz Navas, Elisa María; Torralba, José Manuel

    2014-01-01

    The present work concerns the processing of 7075 Al alloy by cold compaction and hot extrusion of a pre-mixed powder. To this end, a premixed Al-Zn-Mg-Cu powder, Alumix 431D, was uniaxially cold pressed at 600 MPa into cylindrical compacts 25 mm in diameter and 15 mm thick. Subsequently, selected green compacts were subjected to either a delubrication or presintering heat treatment. Extrusion of the powder compacts was performed at 425 degrees C using an extrusion ratio of 25:1. No porosity w...

  10. Combined application of extrusion and irradiation technologies: A strategy oriented for green and cost-effective chemistry

    Directory of Open Access Journals (Sweden)

    Ali Ayoub

    2013-02-01

    Full Text Available Reactive extrusion is an attractive green route for cost-effective polymer processing, which has the potential to enhance the commercial viability of biomass-derived materials. In reactive extrusion, compatibilizers can be generated in the blend preparation through polymer-polymer grafting reactions using functionalized polymers. One very interesting new green strategy for processing is the use of intense UV-irradiation to create free radicals and controllable, ultra-fast reactions. It is reasonable to expect that the use of extrusion/irradiation green technology will be an important way to improve properties and compatibility of renewable biomass- derived polymers. We believe that in the future, many more cost-effective, sustainable extrusion/irradiation reaction processes will be developed to replace inefficient conventional biomass conversion procedures and stimulate the bioproduct-based industry.

  11. Chem-Prep PZT 95/5 for neutron generator applications : development of laboratory-scale powder processing operations.

    Energy Technology Data Exchange (ETDEWEB)

    Montoya, Ted V.; Moore, Roger Howard; Spindle, Thomas Lewis Jr.

    2003-12-01

    Chemical synthesis methods are being developed as a future source of PZT 95/5 powder for neutron generator voltage bar applications. Laboratory-scale powder processes were established to produce PZT billets from these powders. The interactions between calcining temperature, sintering temperature, and pore former content were studied to identify the conditions necessary to produce PZT billets of the desired density and grain size. Several binder systems and pressing aids were evaluated for producing uniform sintered billets with low open porosity. The development of these processes supported the powder synthesis efforts and enabled comparisons between different chem-prep routes.

  12. Prediction of Grain Size for Blade Precision Forging Process under Thermo-Mechanical Coupling

    Institute of Scientific and Technical Information of China (English)

    He YANG; Yuli LIU; Wang CAI; Mei ZHAN

    2003-01-01

    Blade precision forging is a high temperature and large plastic deformation process. Interaction of deformation andheat conduction results in producing large temperature unevenness inside the billet. The unevenness has a greateffect on the mechanical prop

  13. Introdução de ligações cruzadas no LLDPE através de processo de extrusão reativa de graftização do vinil-trimetóxi-silano (VTMS na cadeia polimérica: Efeito das condições de processamento e do sistema reacional Silane grafting and mositure crosslinking of LLDPE by a reactive extrusion process: effect of processing conditions and reaction system

    Directory of Open Access Journals (Sweden)

    Alexandre B. Pessanha

    2011-01-01

    Full Text Available Embora a reticulação do polietileno efetuada através de processo de extrusão reativa, envolvendo a graftização de silanos vinílicos na cadeia polimérica, seja um processo bastante utilizado industrialmente, poucos estudos têm sido publicados sobre a influência das variáveis de processamento nas propriedades do polímero. Neste trabalho, foi avaliado o efeito das condições de processamento e do sistema reacional no índice de fluidez (MFI, no teor de gel e nas propriedades térmicas do polietileno linear de baixa densidade (LLDPE, graftizado com vinil-trimetóxi-silano (VTMS na presença de baixas concentrações de peróxido de dicumila (DCP e reticulado com água. Uma metodologia estatística demonstrou que o teor de silano é a variável de processamento mais significativa, quando a reação é efetuada utilizando 0,02% p/p de DCP. Aumento significativo do teor de gel do LLDPE foi obtido utilizando uma concentração maior de DCP (0,07% p/p. O processo de formação de ligações cruzadas causou aumento na estabilidade térmica e redução significativa no grau de cristalinidade, nas temperaturas de fusão e de cristalização e nas entalpias de fusão do LLDPE. Os espectros de infravermelho (FTIR e o aumento da estabilidade térmica demonstram que houve formação de ligações cruzadas no polímero via pontes siloxano.Although silane-modified polyolefins have become an industrial process, little data have been published on the dependence of silane grafting reactions and the properties of crosslinked polyolefins on reaction parameters. Here we studied the melt grafting of vinyl trimetoxi silane (VTMS onto linear low density polyethylene (LLDPE promoted by dicumyl peroxide (DCP in a single screw extruder followed by crosslinking reaction in hot water. The influence of grafting formulations and processing conditions on the melt flow index (MFI, gel content and thermal properties of grafted and crosslinked LLDPE was evaluated using

  14. 热挤压

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Effects of adding La-rich mischmetal on the microstructure and mechanical properties of hot extruded Mg-8Al alloys; Effects of extrusion conditions on hot extruding characteristics of magnesium alloy;Expert evaluation of hydraulic press reliability; Extrudability improvement and energy consumption estimation in AI extrusion process of a 7003 alloy; Fabrication of composite pipes by multi-billet extrusion technique

  15. Smooth Particle Hydrodynamics Simulation of Micro-Cup-Extrusion Using a Graphit-ic Coating

    Directory of Open Access Journals (Sweden)

    Li Shi-Cheng

    2014-01-01

    Full Text Available Microextrusion is becoming increasingly important for the manufacturing of microcomponents. However, this reduction in scale to a microlevel means that the influence of friction and the need for suitable lubrication are greatly increased. This study therefore looks at the use of a low-friction and highly wear resistant Graphit-ic coating on the mold-forming section of a microextrusion mold, this coating being applied by a closed-field unbalanced magnetron sputter ion plating technique. A microcup of CuZn33 brass alloy was then extruded, with a wall thickness of 0.45 mm, outside diameter of 2.9 mm, and an internal diameter of 2 mm. The experimental results in which extrusion uses the mold coating with Graphit-ic film are compared against the experimental results in which extrusion uses the mold uncoating with Graphit-ic film. This showed that the load was decreased a lot and the self-lubricating solid coating facilitates a smooth extrusion process. As the extrusion rate was quite high, smoothed particle hydrodynamics method simulations of the extrusion process were conducted, these being then compared with the experimental results. These result showed that the SPH simulation can be applied to show the deformation of materials and predict the load trend.

  16. RESEACH ON LUBRICATION IN HOT EXTRUSION OF G3 CORROSION RESISTANT Ni-BASED ALLOY TUBE Ⅰ.Establishment and Application of Glass Lubricating Film Thickness Model%G3镍基耐蚀合金管材热挤压工艺润滑行为研究Ⅰ.玻璃润滑膜厚度模型建立及应用

    Institute of Scientific and Technical Information of China (English)

    王宝顺; 林奔; 张麦仓; 董建新

    2011-01-01

    In the hot extrusion of steel, adequate lubrication can be obtained by placing a glass pad made of compacted glass powder in front of the billet. During the extrusion, the glass pad progressively melts in thin layer, allowing lubrication to be maintained over the entire stroke. However, the thickness of glass pad in a single operation is markedly depends on the process parameters and glass properties. Therefore, the mechanism of glass lubrication film forming and film thickness calculation model has been investigated during hot extrusion of G3 nickel-based alloy tube. Furthermore, combined with FEM code, the operation variables and viscosity of glass lubricant have been systematically researched in the hot extrusion of G3 alloy tube which is conducted on the 6000 t horizontal extrusion press. The results showed that the processing parameters can be optimized using the thickness formulation of lubrication film and glass pad during a single press operation. Moreover, under the practically technical parameters of hot extrusion G3 alloy tube, the requirements of glass viscosity are as follows: softening temperature about 720 ℃; the viscosity coefficient ranges -0.05 ℃-1 to -0.04 ℃-1 when temperature is between 720 and 800 ℃; the viscosity ranges 25 Pa.s to 200 Pa.s during the hot working temperature 1100--1200 ℃.%研究了G3镍基耐蚀合金管材玻璃润滑热挤压工艺中润滑膜的成膜行为,建立了润滑膜厚度的理论计算模型.同时,针对6000 t卧式挤压机,结合G3合金热挤压工艺有限元模拟分析,对热挤压工艺參数和玻璃润滑剂黏度进行了系统的研究.结果表明,可以通过玻璃润滑膜厚度及完成一次热挤压所需玻璃垫厚度的理论计算公式优化G3合金管材热挤压工艺参数,并进一步获得了玻璃润滑剂黏度性质须满足:玻璃粉的软化温度大约为720℃;在720-800℃,玻璃黏温系数在-0.05℃-1和-0.04℃-1之间;热变形温度1100-1200

  17. Hydrostatic extrusion of Cu-Ag melt spun ribbon

    Science.gov (United States)

    Hill, Mary Ann; Bingert, John F.; Bingert, Sherri A.; Thoma, Dan J.

    1998-01-01

    The present invention provides a method of producing high-strength and high-conductance copper and silver materials comprising the steps of combining a predetermined ratio of the copper with the silver to produce a composite material, and melt spinning the composite material to produce a ribbon of copper and silver. The ribbon of copper and silver is heated in a hydrogen atmosphere, and thereafter die pressed into a slug. The slug then is placed into a high-purity copper vessel and the vessel is sealed with an electron beam. The vessel and slug then are extruded into wire form using a cold hydrostatic extrusion process.

  18. Effects of extrusion conditions on the extrusion responses and the quality of brown rice pasta.

    Science.gov (United States)

    Wang, Li; Duan, Wei; Zhou, Sumei; Qian, Haifeng; Zhang, Hui; Qi, Xiguang

    2016-08-01

    This research investigated the effects of extrusion temperature and screw speed on the extrusion system parameters and the qualities of brown rice pasta. The die pressure and motor torque value reached a maximum at 90°C but decreased when the screw speed increased from 80 to 120rpm. The extrusion temperature and screw speed also significantly affected the cooking quality and textural properties of brown rice pasta. The pasta produced at an extrusion temperature of 120°C and screw speed of 120rpm had the best quality with a cooking loss, hardness and adhesiveness of 6.7%, 2387.2g and -7.0g⋅s, respectively, similar to those of pasta made from gluten-free flour. The results indicated that brown rice can be used to produce gluten-free pasta with improved nutrition. PMID:26988508

  19. Effects of extrusion conditions on the extrusion responses and the quality of brown rice pasta.

    Science.gov (United States)

    Wang, Li; Duan, Wei; Zhou, Sumei; Qian, Haifeng; Zhang, Hui; Qi, Xiguang

    2016-08-01

    This research investigated the effects of extrusion temperature and screw speed on the extrusion system parameters and the qualities of brown rice pasta. The die pressure and motor torque value reached a maximum at 90°C but decreased when the screw speed increased from 80 to 120rpm. The extrusion temperature and screw speed also significantly affected the cooking quality and textural properties of brown rice pasta. The pasta produced at an extrusion temperature of 120°C and screw speed of 120rpm had the best quality with a cooking loss, hardness and adhesiveness of 6.7%, 2387.2g and -7.0g⋅s, respectively, similar to those of pasta made from gluten-free flour. The results indicated that brown rice can be used to produce gluten-free pasta with improved nutrition.

  20. Research on Effect of Regenerative Burner of Different Combination Mode on Billet Burning%不同组合方式的蓄热式烧嘴对钢坯烧损的影响探究

    Institute of Scientific and Technical Information of China (English)

    朱森林; 朱锦铭

    2012-01-01

    The effect of double regenerative burner on product quality resulting from the iron billet oxidation scaling loss and economic benefits is presented. The basic conditions of iron emerging oxide in heating process of the billet are analyzed. Through the comparison with the heating furnace burner layout, the heating furnace construction process in the second period is optimized and improved, so that the oxidation loss is reduced and the quality of products is improved.%提出了双蓄热式烧嘴对钢坯烧损产生的氧化铁皮对产品品质和经济效益的影响.分析了钢坯在加热过程中产生氧化铁皮的基本条件.通过对比一期加热炉烧嘴布置方式,在二期加热炉建设过程中进行了优化改进,达到了减少氧化烧损、提高产品品质的目的.

  1. Development of expanded extrusion food products for an Advanced Life Support system.

    Science.gov (United States)

    Zasypkin, D V; Lee, T C

    1999-01-01

    Extrusion processing was proposed to provide texture and to expand the variety of cereal food products in an isolated Advanced Life Support (ALS) system. Rice, wheat, and soy are the baseline crops selected for growing during long-term manned space missions. A Brabender single-screw laboratory extruder (model 2003, L/D 20:1), equipped with round nozzles of various lengths, was used as a prototype of a small-size extruder. Several concepts were tested to extend the variety and improve the quality of the products, to decrease environmental loads, and to promote processing stability. These concepts include: the blending of wheat and soybean flour, the extrusion of a coarser rice flour, separation of wheat bran, and optimization of the extruder nozzle design. An optimal nozzle length has been established for the extrusion of rice flour. Bran separating was necessary to improve the quality of wheat extrudates.

  2. 75 FR 80527 - Aluminum Extrusions From China

    Science.gov (United States)

    2010-12-22

    ... Republic of China: Postponement of Final Determination of Sales at Less Than Fair Value, 75 FR 73041... Sales at Less Than Fair Value, and Preliminary Determination of Targeted Dumping, 75 FR 69403, November... Affirmative Countervailing Duty Determination, 75 FR 54302, September 7, 2010, and Aluminum Extrusions...

  3. Energy aspects in food extrusion-cooking

    NARCIS (Netherlands)

    Janssen, L.P.B.M.; Moscicki, L.; Mitrus, M.

    2002-01-01

    Theoretical and practical energy balance considerations in food extrusion-cooking are presented in the paper. Based on the literature review as well as on own measurement results, the baro-thermal treatment of different vegetable raw materials is discussed together with the engineering aspects of th

  4. The Favourable Choice of the Shape of Billet's Contact Surface to Quality of Extruded Aluminium Profiles

    OpenAIRE

    G. Skorulski; J. Piwnik; Baranowski, P.

    2010-01-01

    The theoretical and experimental method of optimization the aluminium billet’s contact surface during extrusion have been presented inthis paper. The theoretical assumption, based on welding criteria, have been confirmed by experimental researches. The technique ofmeasurement has been shown as well. Experiments are made using plasticine as a substiute material. Some kind of different variants have been investigated. The theory and experiments have been provided to optimize the modeling shape ...

  5. Repetitive fracturing during spine extrusion at Unzen volcano, Japan

    Science.gov (United States)

    Lamb, O. D.; De Angelis, S.; Umakoshi, K.; Hornby, A. J.; Kendrick, J. E.; Lavallée, Y.

    2015-12-01

    Rhythmic seismicity associated with spine extrusion is a well-documented phenomenon at a number of dome-forming volcanic systems. At Unzen volcano, Japan, a 4-year dome-forming eruption concluded with the emplacement of a spine from October 1994 to February 1995, offering a valuable opportunity to further investigate seismogenic processes at dome-forming volcanoes. Using continuous data recorded at a seismic station located close to the dome, this study explores trends in the seismic activity during the extrusion of the spine. We identify a total of 12 208 volcano-seismic events in the period between October 1994 and February 1995. Hourly event counts indicate cyclic activity with periods of ∼ 40 to ∼ 100 h, attributed to pulsatory ascent defined by strain localisation and faulting at the conduit margins. Waveform correlation revealed two strong clusters (a.k.a. multiplets, families) which are attributed to fracturing along the margins of the shallow, ascending spine. Further analysis indicates variable seismic velocities during the spine extrusion as well as migration of the cluster sources along the spine margins. Our interpretation of the results from seismic data analyses is supported by previously published field and experimental observations, suggesting that the spine was extruded along an inclined conduit with brittle and ductile deformation occurring along the margins. We infer that changes in stress conditions acting on the upper and lower spine margins led to deepening and shallowing of the faulting sources, respectively. We demonstrate that the combination of geophysical, field and experimental evidence can help improve physical models of shallow conduit processes.

  6. Effect of a Hot Rolling Process on the Mechanical Behavior of 9Cr-1Mo Steel

    International Nuclear Information System (INIS)

    Ferritic-martensitic steel (F/M steel) has been considered as the one of the main candidate cladding materials in the design of sodium-cooled fast reactor (SFR) in that it has higher thermal conductivity as well as dimensional stability under irradiation when compared as austenitic stainless steel. Optimization of the alloying element as well as manufacturing process has been carried out for the purpose of enhancing thermal creep property under the operation temperature. Among these, hot working process can be applied in the field of hot extrusion at the manufacture of the actual cladding where the hollow billet was formed into the intermediate product. In terms of these, it has been tried to enhance the high temperature mechanical property of the F/M steel by changing hot working temperature or the degree of the hot working rate to initiate the preferential precipitation of the MX particle at the metal matrix and the some works have been proposed. However, lots of the works regarding the effect of the hot working process on the behavior of the F/M steel have yet to be gathered. The objectives of the study are to analyze the effect of such a hot rolling process on the mechanical property of the F/M steel and to assess the hot rolling parameter in the field of a cladding manufacture

  7. Controls on extrusion at mid-ocean ridges

    Science.gov (United States)

    Buck, W. Roger; Carbotte, Suzanne M.; Mutter, Carolyn

    1997-10-01

    A magma lens can erupt to form extrusives only if it is under greater pressure than the static pressure in a column of magma reaching from the lens to the surface. The excess pressure results partly from overburden pressure caused by the presence of high- and low-density rocks (dikes and extrusives, respectively) above the lens. The thicker the pile of low-density extrusives, the lower the average overburden density. Thus, extrusion above a lens should be self-regulating, in that thickening the extrusive layer reduces the driving pressure for subsequent eruptions. Flexural stresses may affect extrusion by altering the pressure on a magma chamber. For ridges lacking an axial valley, we predict that deeper magma lenses should correlate with thicker extrusive layers, consistent with recent observations.

  8. Three dimensional simulation of macrosegregation in steel billets by a meshless method

    Science.gov (United States)

    Vertnik, R.; Šarler, B.

    2016-03-01

    There is a continuously developing need for benchmarking of solidification simulations - from the theoretical as well as from the applied points of view. The history of related benchmarking shows differences of the results between different numerical methods, and differences in comparison with the experiments when solving even quite simple solidification situations. The present benchmark test proposes a three dimensional version of the recently developed two dimensional solidification benchmark of the continuous casting with turbulent fluid flow and solidification with macrosegregation. The macroscopic transport equations for mass, momentum, energy, species, turbulent kinetic energy and dissipation rate are considered. Turbulent effects are incorporated through the solution of a low-Re turbulence model. The solidification system is treated by the mixture-continuum model, where the mushy zone is modeled as a Darcy porous media with Kozeny-Karman permeability relation and columnar solid phase moving with the casting velocity. The Fe-C binary phase diagram and the lever rule microsegregation model are used to obtain the carbon segregation in the billet. The transport equations are solved by our newly developed and efficient meshless numerical technique, based on local collocation with radial basis functions and fractional step velocity- pressure coupling. The presented results represent first simulations of a three-dimensional solidification problem by a meshless method.

  9. Analysis of fracture modes during extrusion and drawing of bimetal rods or wire. Analytical study of drawing and extrusion of superconducting filamentary wires: fracture problems and evaluation of temperature rise. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Avitzur, B.; Wu, R.; Chou, Y.T.; Talbert, S.

    1984-01-09

    Based on the upper-bound theorem in limit analysis, a theoretical model describing sound flow, core fracture, and sleeve fracture in bimetal rods and wire during extrusion and drawing was developed. The variables affecting core and sleeve fracture are: reduction in area, die geometry, friction, relative size and strength of the core, and applied surface tractions. Within the wide range of combinations of these process variables, only a small range permits co-extrusion and codrawing without fracture. Criteria for the prevention of core and sleeve fracture during co-extrusion and core fracture during co-drawing were developed and presented graphically in this study. The results were applied to the central burst problem during extrusion and drawing of homogeneous materials.

  10. NUMERICAL SIMULATION STUDY ON DEFORMATION UNIFORMITY OF EQUAL CROSS SECTION LATERAL EXTRUSION

    Institute of Scientific and Technical Information of China (English)

    Z.L. Chang; J.L. Song; N.H. Hao

    2004-01-01

    Equal cross section lateral extrusion (ECSLE) is an effective method realizing pure shear deformation. The influence of friction factor on the deformation uniformity of ECSLE was investigated with rigid plastic finite element method. The result shows that the non-uniform deformation in extrusion is caused mainly by the friction between workpiece and die. The higher the friction factor is, the more uneven plastic deformation resulted in extruded workpiece. The relation curve of deformation uniformity vs. friction factor was drawn based on the analysis result. The curve can be used as a basis of ECSLE process design.

  11. Influence of Mg Content on Deformability of AlMg Alloys during Extrusion

    Directory of Open Access Journals (Sweden)

    Leśniak D.

    2016-03-01

    Full Text Available In this study the research on deformability of AlMg alloys with high Mg contents in extrusion was carried out. The different shapes from AlMg alloys containing 3.5%, 4.5% and 5.5% of Mg were extruded on 500 T semi-industrial press by using one-hole and multi-hole flat dies. The extrudates surface quality was under investigations in relation with the temperature-speed parameters of the extrusion process. The metal exit speed was estimated depending on the extrudates shape, wall thickness and Mg content. The alloy’s border solidus and liquidus temperatures were also determined.

  12. Effect of fermentation and extrusion on the release of selected minerals from lupine grain preparations

    Directory of Open Access Journals (Sweden)

    Rafał W. Wójciak

    2009-09-01

    Full Text Available Introduction. Antinutritional factors in legumes lower the nutritional value of foods by lowering the digestibility or bioavailability of nutrients. Technological processes applied in food production (e.g. extrusion, fermentation, germination may influence the leguminous seeds matrix composition which in consequence may affect (improve or decrease mineral bioaccessibility and uptake in animals and humans. The aim of this study was to determine the effect of fermentation and extrusion processing, as well as their combination, on the potential availability of Fe, Cu, and Zn from lupine grain preparations. Materials and methods. The content and the release of Fe, Cu and Zn from three different lupine species (Lupinus albus, Lupinus luteus, Lupinus angustifolius was determined. The samples were subjected to enzymatic digestion under in vitro conditions. The content of minerals in lupine grains before and after enzymatic digestion was determined by the flame atomic absorption spectrometry. Results. The degree of release of Fe, Cu, and Zn from dehulled lupine grains was higher than from whole grains. Fermentation processing increased the degree of Fe release, extrusion decreased the degree of Cu release, while the extrusion after fermentation processing increased the degree of Fe release from lupine grain preparations. Conclusions. The degree of mineral release from lupine grains depends on the hull content, technological processing applied and the lupine variety.

  13. Optimization of microstructure development: application to hot metal extrusion

    Science.gov (United States)

    Medina, E. A.; Venugopal, S.; Frazier, W. G.; Medeiros, S.; Mulhns, W. M.; Chaudhary, A.; Irwin, R. D.; Srinivasan, R.; Malas, J. C.

    1996-12-01

    A new process design method for controlling microstructure development during hot metal deformation processes is presented. This approach is based on modern control theory and involves state- space models for describing the material behavior and the mechanics of the process. The challenge of effectively controlling the values and distribution of important microstructural features can now be systematically formulated and solved in terms of an optimal control problem. This method has been applied to the optimization of grain size and certain process parameters such as die geometry profile and ram velocity during extrusion of plain carbon steel. Various case studies have been investigated, and experimental results show good agreement with those predicted in the design stage.

  14. Optimization of microstructure development: Application to hot metal extrusion

    Energy Technology Data Exchange (ETDEWEB)

    Medina, E.A.; Venugopal, S.; Frazier, W.G.; Medeiros, S.; Mullins, W.M.; Chaudhary, A.; Malas, J.C. [WL/MLIM, Wright-Patterson AFB, OH (United States); Irwin, R.D. [Ohio Univ., Athens, OH (United States). School of Electrical Engineering and Computer Science; Srinivasan, R. [Wright State Univ., Dayton, OH (United States). Mechanical and Materials Engineering Dept.

    1996-12-01

    A new process design method for controlling microstructure development during hot metal deformation processes is presented. This approach is based on modern control theory and involves state-space models for describing the material behavior and the mechanics of the process. The challenge of effectively controlling the values and distribution of important microstructural features can now be systematically formulated and solved in terms of an optimal control problem. This method has been applied to the optimization of grain size and certain process parameters such as die geometry profile and ram velocity during extrusion of plain carbon steel. Various case studies have been investigated, and experimental results show good agreement with those predicted in the design stage.

  15. THE IMPACT OF EXTRUSION ON THE BIOGAS AND BIOMETHANE YIELD OF PLANT SUBSTRATES

    Directory of Open Access Journals (Sweden)

    Krzysztof Pilarski

    2016-09-01

    Full Text Available The objective of the present work was to determine the effect of pretreatment by extrusion on the biogas and biomethane yield of lignocellulosic substrates such as maize silage and maize straw silage. The biogas yields of the substrates before and after treatment were compared. Moreover, energy efficiency of pretreatment by extrusion was analyzed in order to assess the applicability of the process in an agricultural biogas plant. Extrusion tests were carried out in a short single-screw extruder KZM-2 in which the length-to-diameter ratio of the screw was 6:1 and rotational speed was 200 rpm. The biogas yield tests of the plant substrates after extrusion were carried out in a laboratory scale, using 15 biofermenters operated in a periodic manner, at a constant temperature of 39°C (mesophilic digestion and controlled pH conditions. The gas-emission analysis was performed using a certified gas analyzer from Geotech GA5000. Pretreatment by extrusion was observed to improve the quantity of methane generated: in terms of fresh matter for maize silage subjected to extrusion, the methane yield was 16.48% higher than that of the non-extruded silage. On the other hand, maize straw silage after extrusion gave 35.30% more methane than did the same, non-extruded, material. Differences in yields relative to dry organic matter are also described in this paper. Taking into account the amount of energy that is spent on pretreatment and the generated amount of methane, the energy balance for the process gives an idea of the economics of the operation. For maize silage, energy efficiency was lower by 13.21% (-553.2 kWh/Mg, in contrast to maize straw silage, where the increase in energy was 33.49% (678.4 kWh/Mg. The obtained results indicate that more studies on the pretreatment and digestion of maize silage are required in order to improve the efficiency of its use for making biogas. To fully utilize its potential, it is necessary to know thoroughly the effect of

  16. Cold Extrusion of Metal Plastic Forming Process on Metal Flow Lines and Grain Structure Impacts of Electro-hydraulic Vibration Applied in%电液颤振对冷挤压塑性成形件金属流线及晶粒组织的影响

    Institute of Scientific and Technical Information of China (English)

    杨庆华; 洪潇潇; 王志恒; 鲍官军; 胡新华; 薛军义

    2015-01-01

    Cold extrusion process had some disadvantages,such as gigantic metal deformation re-sistance,mold wear,etc.a new type of cold extrusion process was proposed,where vibration excitation signals were applied in the cold extrusion process.Using DEFORM-3D finite element analysis soft-ware,the system simulation models were built and the forming process was simulated on whether the vibration was applied to this process.Simulation results show that the signal can be applied to facili-tate the metal flow,and the metal flow rate reaches 62.4 mm/s.The degree of deformation of the mesh flow lines is smaller than that in the condition of traditional squeeze mode.A kind of electro-hy-draulic vibration experimental platform and die were designed for this project.Experiments were com-pleted on the conditions of whether the vibration was applied to this process.Etching molded parts with 4% Nital,and SEM was used to observe the part sections.Experimental results show that after the application of vibration signals in cold extrusion,the grain size reduce from about 3.3 ~5.0μm to 1.7 ~3.3 μm,grain deformation becomes more uniform,deformation tissue becomes more dense,me-tallic fibrous tissue becomes finer and longer.%针对冷挤压成形过程中金属变形抗力大、模具易磨损等不足,提出一种新型冷挤压工艺,即在冷挤压成形过程中引入振动激励信号。运用 DEFORM-3D 有限元分析软件构建系统仿真模型,分别在有无施加颤振两种挤压方式下进行模拟仿真。仿真结果表明,施加颤振信号能促进金属的流动,金属流动速度达到62.4 mm/s,网格流线变形程度比传统挤压方式下的变形程度小。设计了电液式颤振冷挤压实验平台及模具,分别在有无施加颤振两种挤压方式下进行实验,并将所得成形零件用体积分数为4%的硝酸酒精溶液腐蚀,利用扫描电镜观察零件剖面。实验结果表明,施加颤振信号后,晶粒由原来的大小为3.3~5.0μm

  17. Axi-symmetric forward spiral extrusion, a kinematic and experimental study

    International Nuclear Information System (INIS)

    Research highlights: → The accumulated strain in AFSE, a new extrusion process, is the result of circumferential velocity gradient along extrusion axis. → The effective strain depends on the radius and helix angle only while independent of the chamfer geometry. → Embedded wires were used to verify the validity of the derived velocity field during AFSE. → The velocity field and the observations conform well and the proposed kinematics is a reliable model for AFSE. - Abstract: A modified axi-symmetric forward spiral extrusion process has been proposed here to allow for a near zero area reduction process. The axi-symmetric forward spiral extrusion, AFSE, can be carried out through a die with a number of engraved spiral grooves. This paper investigates the kinematics of the AFSE process. A velocity field is derived using principle of mass conservation along the extrusion axis. The proposed model has been developed to calculate strain components in the deformation zone during the process. An experimental method has been designed which uses composite lead samples with embedded copper wires to trace the strain path to verify the proposed velocity field. A good agreement between experimental results and the proposed analytical model was observed. The proposed velocity field, verified by experimental results, shows that the deformation develops away from the AFSE die-sample interface. A linear gradient of velocity in the radial direction was observed which is in good agreement with the proposed velocity field. Based on the estimated strains, velocity gradient, and nearly no change in sample cross section during AFSE, the process seems to have good potential for application as a new severe plastic deformation process in both continuous and batch modes.

  18. Polymeric formulations for drug release prepared by hot melt extrusion : application and characterization

    NARCIS (Netherlands)

    Stanković, Milica; Frijlink, Henderik W; Hinrichs, Wouter L J

    2015-01-01

    Over the past few decades hot melt extrusion (HME) has emerged as a powerful processing technology for the production of pharmaceutical solid dosage forms in which an active pharmaceutical ingredient (API) is dispersed into polymer matrices. It has been shown that formulations using HME can provide

  19. Analysis of Key Technologies and Equipments Development of Largescale Melted Extrusion Manufacturing Systems

    Institute of Scientific and Technical Information of China (English)

    Lei ZHANG; Sheng CHEN; Yongnian YAN; Renji ZHANG

    2003-01-01

    To develop large-scale RP systems used to producing functional parts and large-sized models has become an urgentcall now. In this paper, a large-scale RP system, MEM600-l, based on the melted extrusion manufacturing (MEM)process has been developed success

  20. Definition of a JA2 equivalent propellant to be produced by continuous solvent-less extrusion

    NARCIS (Netherlands)

    Manning, T.G.; Leone, J.; Zebregs, M.; Ramlal, D.R.; Driel, C.A. van

    2013-01-01

    The aim of this work is to demonstrate the manufacturing of a propellant by solvent-less continuous twin screw extrusion processing while maintaining gun performance characteristics of conventional JA-2 propellant. This is elucidated by explicitly researching the relationship between interior ballis

  1. Effects of Steam Conditioning and Extrusion Temperature on Some Anti-nutritional Factors of Soyabean (Glycine max) for Pet Food Applications

    OpenAIRE

    Purushotham, B; P. M. Radhakrishna; Sherigara, B. S.

    2007-01-01

    Extrusion processing of vegetable ingredients such as soyabean (Glycine max) characteristically depends on associating process conditions that influence the product qualities. The process parameters were optimized for extrusion of steam-conditioned material in order to obtain the maximum nutritive value by inactivating the anti-nutritional factors such as urease, trypsin inhibitors and lipase. The processing conditions such as moisture content, temperature and time were precisely controlled t...

  2. Study of the corn-rice powder characteristic parameters in twin-screw extrusion process%玉米和大米混合粉双螺杆挤压特征参数的研究

    Institute of Scientific and Technical Information of China (English)

    张志森; 李爱军

    2009-01-01

    For the purpose of finding the inner relations of extrusion characteristic parameters and guiding the extrusion practice. 2-factors and 3-levels orthogonal experiments are carried out on the twinscrew extruder with the corn-rice powder as the materials. The factors are set to be screw rate and feed rate; the indices are set to be: inner pressure, die outlet temperature and generator current. The experimental results are inspected with the single index regression analysis, the results show that the screw rate has the significant influence on the variables of barrel inner pressure, die outlet temperature and generator current, while the feed rate only impact significantly on the barrel inner pressure and generator current. After the response analysis of the original variables, the desired experimental conditions are obtained. The factors should be set as: screw rate =150 r/min, feed rate= 14 r/min.%为寻求挤压机特征参数之间的内部关系,指导挤压生产加工实践,以玉米粉和大米粉为原料,在双螺杆挤压机上进行2因素3水平的正交试验.试验因素为:螺杆转速和喂料速率;试验指标为机筒内部压力、模头出口温度和主机电流.通过单指标回归分析,表明螺杆转速对机筒内部压力、模头出口温度及主机电流3者影响均显著,而喂料速率仅时机筒内部压力和主机电流影响显著;进一步通过响应面分析,得到较好的试验条件为:螺杆转速150 r/min:,喂料速率:14 r/min.

  3. Learning through Plastic Filament Extrusion

    Science.gov (United States)

    Orr, Taylor; Flowers, Jim

    2015-01-01

    3D printing is becoming ever more popular in both the manufacturing world as well as in technology and engineering education classrooms all over the United States. 3D printing is an additive manufacturing process in which successive layers of material are built up to produce three-dimensional objects from computer-aided design (CAD) files, making…

  4. Distribution of E-cadherin and ß-catenin in relation to cell maturation and cell extrusion in rat and mouse small intestines

    DEFF Research Database (Denmark)

    Larsson, Lars-Inge

    2006-01-01

    In the small intestines, cell renewal from stem cells present in the crypts is balanced by cell extrusion from the tips of the villi. The mechanism by which extrusion occurs is unknown. Recent in vitro data suggested that loss of E-cadherin could contribute to cell extrusion and induction...... of programmed cell death (PCD) in mouse small intestinal epithelium. We have studied if this also occurs in the intact rodent small intestine. Our results confirm that extruded cells are negatie for E-cadherin. However, loss of the E-cadherin-interacting protein ß-cetenin preceded both extrusion and loss of E......-cadherin. Thus, all extruded cells as well as all cells in the process of extrusion lacked staining for ß-catenin. Moreover, almost 80% of all cells undergoing programmed cell death, as detected by the TUNEL reaction, lacked ß-catenin whereas over 70% of such cells were positive for E-cadherin. However, most...

  5. Extrusion foaming of protein-based thermoplastic and polyethylene blends

    Science.gov (United States)

    Gavin, Chanelle; Lay, Mark C.; Verbeek, Casparus J. R.

    2016-03-01

    Currently the extrusion foamability of Novatein® Thermoplastic Protein (NTP) is being investigated at the University of Waikato in collaboration with the Biopolymer Network Ltd (NZ). NTP has been developed from bloodmeal (>86 wt% protein), a co-product of the meat industry, by adding denaturants and plasticisers (tri-ethylene glycol and water) allowing it to be extruded and injection moulded. NTP alone does not readily foam when sodium bicarbonate is used as a chemical blowing agent as its extensional viscosity is too high. The thermoplastic properties of NTP were modified by blending it with different weight fractions of linear low density polyethylene (LLDPE) and polyethylene grafted maleic anhydride (PE-g-MAH) compatibiliser. Extrusion foaming was conducted in two ways, firstly using the existing water content in the material as the blowing agent and secondly by adding sodium bicarbonate. When processed in a twin screw extruder (L/D 25 and 10 mm die) the material readily expanded due to the internal moisture content alone, with a conditioned expansion ratio of up to ± 0.13. Cell structure was non-uniform exhibiting a broad range cell sizes at various stages of formation with some coalescence. The cell size reduced through the addition of sodium bicarbonate, overall more cells were observed and the structure was more uniform, however ruptured cells were also visible on the extrudate skin. Increasing die temperature and introducing water cooling reduced cell size, but the increased die temperature resulted in surface degradation.

  6. Key Problems in Microforming Processes of Microparts

    Institute of Scientific and Technical Information of China (English)

    Chunju WANG; Debin SHAN; Bin GUO; Jian ZHOU; Lining SUN

    2007-01-01

    From the viewpoint of production engineering, microforming is considered as an effective process to fabricate various microparts. Several key problems in microforming processes were investigated. A new microforming apparatus with a high stiffness piezoelectric actuator as the punch driver was developed to produce microparts.To improve the forming abilities and locate the billets, a floating microdie was designed. The size effects of the billets and die cavities on the microforming abilities were studied with upsetting and coining tests, respectively.And the isothermal microforming process of microgears was performed with the developed microforming apparatus. Several analysis methods were used to evaluate the forming quality of the microparts.

  7. Effect of Temperature and Ram Speed on Isothermal Extrusion for Large-size Tube with Piece-wing

    Institute of Scientific and Technical Information of China (English)

    He YANG; Jun ZHANG; Yangmin HE; Bingtao HAN

    2005-01-01

    Heat energy change during the extrusion of 7075 aluminium alloy large-size tube with piece-wing in a container was analyzed. Extrusion load vs ram displacement diagrams and exit temperature vs ram displacement diagrams at various speeds were obtained by 3D FEM simulation. Results show that the exit temperature becomes higher as the ram speed and displacement increase. For large-size tube with piece-wing, there is certainly a curve of ram speed decreasing with increasing ram displacement, which enables isothermal extrusion to be achieved. Therefore,an attempt was made to divide the working stroke into five different zones. Each of them has a preset speed that decreases from the ram displacement beginning to the ending. And then, new exit temperature vs ram displacement diagram was obtained by 3D FEM simulation for the five different speeds. It is shown that the variation of exit temperature is very small. Through the above research, a basic method for realizing isothermal extrusion of 7075large-size tube with piece-wing was obtained, that is, the working stroke was divided into several different zones with a decreasing speed during extrusion, each zones' speed was real-time adjusted on the feedback signal of exit temperature by proportional hydraulic valve through closed-loop control. The engineering experiment verification was carried out on 100 MN aluminium extrusion press with oil-driven double action. The experimental results of the exit temperature agrees with the simulation ones. The achievements of this study may serve as a significant guide to the practice of the relevant processes, particularly for isothermal extrusion. The verified method has been used in the design and manufacture of 125 MN aluminium extrusion press with oil-driven double action.

  8. The influence of extrusion on the content of polyphenols and antioxidant/antiradical activity of rye grains (Secale cereale L.

    Directory of Open Access Journals (Sweden)

    Dorota Gumul

    2007-12-01

    Full Text Available The aim of the study was to check the influence of extrusion on the content of polyphenol and antioxidant/antiradical activity of rye grains. The extrudates prepared from three cultivars of rye were obtained at different process parameters. Total polyphenol, antioxidant and antiradical activity was measured in the samples. Extrusion resulted in a decrease of total polyphenol content (TPC on average by 40% in rye grains, and the largest loss of endogenic phenolic compounds was observed at the extrusion conditions: 20% moisture of raw material and 120°C. Extrudates obtained at: 14% moisture of raw material and 180°C exhibited either increase of these compounds or no change. It was found that rye extrudates exhibited the highest antiradical activity (measured by the methods with DPPH and ABTS when raw material contained 14% of moisture and at temperature of the extrusion – 180°C, while the lowest when the parameters were 20% and 120°C. Antioxidant activity in beta-carotene-linoleate model system was high when rye extrusion was performed at 14% and 20% moisture and temperature 180°C. The negative influence of extrusion on the antioxidant activity of rye grains was observed at 20% moisture and 120°C.

  9. CHARACTERIZATION OF NEW TOOL STEEL FOR ALUMINUM EXTRUSION DIES

    OpenAIRE

    José Britti Bacalhau; Fernanda Moreno Rodrigues; Rafael Agnelli Mesquita

    2014-01-01

    Aluminum extrusion dies are an important segment of application on industrial tools steels, which are manufactured in steels based on AISI H13 steel. The main properties of steels applied to extrusion dies are: wear resistance, impact resistance and tempering resistance. The present work discusses the characteristics of a newly developed hot work steel to be used on aluminum extrusion dies. The effects of Cr and Mo contents with respect to tempering resistance and the Al addition ...

  10. Modelling the extrusion of preforms for microstructured optical fibres

    Science.gov (United States)

    Tronnolone, Hayden; Stokes, Yvonne; Crowdy, Darren

    2013-11-01

    Owing to a novel design, microstructured optical fibres (MOFs) promise the realisation of fibres with effectively any desired optical properties. MOFs are typically constructed from glass and employ a series of air channels aligned along the fibre axis to form a waveguide. The construction of MOFs by first extruding a preform and then drawing this into the final fibre has the potential to produce fibres on an industrial scale; however, this is hindered by a limited understanding of the fluid flow that arises during this process. We focus on the extrusion stage of fabrication and discuss a model of the fibre evolution based upon complex-variable techniques. The relative influence of the various physical processes involved is discussed, along with limitations of the model.

  11. Gel-extrusion: A new continuous forming technique

    Energy Technology Data Exchange (ETDEWEB)

    Millan, A.J. [Department of Materials, IUT Federico Rivero Palacios, Caracas (Venezuela); Santacruz, I.; Sanchez-Herencia, A.J.; Nieto, M.I.; Moreno, R. [Instituto de Ceramica y Vidrio, CSIC, Camino de Valdelatas s/n, E-28048, Cantoblanco, Madrid (Spain)

    2002-12-01

    In recent years a variety of direct shaping methods has been developed for the near-net shaping of ceramic powders. The main aim in developing these methods is to provide a simple route for manufacturing bulk complex-shaped bodies with increased green resistance in order to reduce or avoid final machining, which is the most expensive step in the fabrication process. This communication reports a novel processing route for the continuous manufacture of ceramic and/or metal hollow or solid bodies based on the extrusion of aqueous suspensions that contain a small amount (<1 wt.-%) of a gelling additive that gelates on passing through a refrigerated die. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  12. Continuous Severe Plastic Deformation Processing of Aluminum Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Raghavan Srinivasan (PI); Prabir K. Chaudhury; Balakrishna Cherukuri; Qingyou Han; David Swenson; Percy Gros

    2006-06-30

    by SPD techniques. This combination of properties makes UFG metals produced by SPD very attractive as machining, forging or extrusion stock, both from the point of view of formability as well as energy and cost saving. However, prior to this work there had been no attempt to transfer these potential benefits observed in the laboratory scale to industrial shop floor. The primary reason for this was that the laboratory scale studies had been conducted to develop a scientific understanding of the processes that result in grain refinement during SPD. Samples that had been prepared in the laboratory scale were typically only about 10-mm diameter and 50-mm long (about 0.5-inch diameter and 2-inches long). The thrust of this project was three-fold: (i) to show that the ECAE/P process can be scaled up to produce long samples, i.e., a continuous severe plastic deformation (CSPD) process, (ii) show the process can be scaled up to produce large cross section samples that could be used as forging stock, and (iii) use the large cross-section samples to produce industrial size forgings and demonstrate the potential energy and cost savings that can be realized if SPD processed stock is adopted by the forging industry. Aluminum alloy AA-6061 was chosen to demonstrate the feasibility of the approach used. The CSPD process developed using the principles of chamber-less extrusion and drawing, and was demonstrated using rolling and wire drawing equipment that was available at Oak Ridge National Laboratory. In a parallel effort, ECAE/P dies were developed for producing 100-mm square cross section SPD billets for subsequent forging. This work was carried out at Intercontinental Manufacturing Co. (IMCO), Garland TX. Forging studies conducted with the ECAE/P billets showed that many of the potential benefits of using UFG material can be realized. In particular, the material yield can be increased, and the amount of material that is lost as scrap can be reduced by as much as 50%. Forging

  13. Experimental and finite element simulations of cold pressure welding of aluminium by divergent extrusion

    International Nuclear Information System (INIS)

    In the present investigation, the aptness of the divergent extrusion process in simulating cold pressure welding (CPW) is further documented and explored. As a starting point, the situation existing both prior to and after cold bonding is adequately reproduced using finite element (FE) modelling. Combined extrusion and joining experiments are then carried out to unravel the conditions under which cold bonding takes place in commercial purity aluminium. Based on three-point bend testing and fracture surface investigations in the scanning electron microscope (SEM), it is observed that bond initiation occurs gradually during the course of the extrusion process. Full metallic bonding is achieved when the surface exposure, as determined by the x-component of the strain acting in the extrusion direction, reaches a value of 0.97. This surface exposure is comparable to that reported for bond formation using conventional CPW and cold roll bonding (CRB) in the presence of oxide and lubricant films at the mating interfaces under similar contact pressure conditions.

  14. Effect of extrusion, espansion and toasting on the nutritional value of peas, faba beans and lupins

    Directory of Open Access Journals (Sweden)

    Filippo Rossi

    2010-01-01

    Full Text Available An assessment was made of the effect that different treatments (toasting, expansion, extrusion have on the nutritionalvalue of protein plants (pea, faba bean, lupin. In a randomized block design, feeds were screened for enzymaticdigestibility of starch and protein, N solubility and in vitro protein degradability. Expansion and extrusion cause increasedstarch enzymatic degradability while toasting produced virtually no effects. In peas this value increased from 11.80% inmeal to 39.70% in the extruded product; 85.37% is the percentage for the expanded product, while 10.90% is the starchdigestibility value for toasted peas. In faba beans the extrusion process increased starch digestibility from 11.39% to85.05%, while in extruded lupins a complete starch hydrolysis was obtained, while in the meal the polysaccharide digestionwas 54.48%.The expansion and extrusion processes significantly decreased rumen degradability during the first 8 hours of incubation.Toasted peas had lower degradability if compared with controls but not with the other treatments. The onlypotentially alternative source to soybean is the extruded faba bean. In spite of its lower protein content, this feed ischaracterized by a considerably lower in vitro protein degradability than soybean. This implies that the digestible foodprotein content is comparable (124.90 g/kg DM to that of soybean (109.78 g/kg DM and definitely higher than thatof all other protein plants.

  15. Deformation and microstructure characterization during semi-solid extrusion of Al-4Cu-Mg alloy

    Institute of Scientific and Technical Information of China (English)

    LU Ya-lin; LI Miao-quan; LI Xing-cheng

    2006-01-01

    Effects of the process parameters, including deformation temperature, punch velocity and extrusion ratio, on the deformation and microstructure characterization during the semi-solid extrusion of Al-4Cu-Mg alloy, were investigated. The experimental results show that the load decreases with an increase of deformation temperature and/or a decrease of punch velocity.When the displacement is more than 4 mm, the load decreases significantly with an increase of the deformation temperature, which is related to the high liquid fraction. The microstructure varies with the process parameters and deformation regions. It can be found that the dynamic recovery occurs during the semi-solid extrusion of Al-4Cu-Mg alloy at lower deformation temperature.Subsequently, the microstructure elongated gradually polygonizes with an increase of deformation temperature. So, the higher deformation temperature should be chosen during the semi-solid extrusion of Al-4Cu-Mg alloy because the grains polygonized and high liquid fractions are beneficial to deformation.

  16. Design of an extrusion screw and solid fuel produced from coconut shell

    Directory of Open Access Journals (Sweden)

    Madhiyanon, T

    2006-03-01

    Full Text Available The objectives were to design an extrusion screw to produce biomass solid fuel in a cold extrusion process, and investigate the effects of molasses used as a selected adhesive on the physical properties of extruded products. The material employed consisted of crushed coconut shell char and coconut fiber char mixed at a ratio of 40:60. The ratios of molasses in the mixture were 10:100, 15:100 and 20:100 (by weight and the extrusion die angles were 1.0, 1.1, 1.2, and 1.3 degrees gradation per experiment. The experimental results showed that the newly designed screw could function properly in the output range 0.75-0.90 kg/min, which is close to the design value. Regarding the molasses's effect on solid fuel properties, increasing the share of molasses was positive for both output and strength of the resulting briquettes, whereas the results of increasing die angle showed decreases in both output and strength. The compressive strength varied between 2.49-2.87 MPa in all circumstances, which was considerably higher than acceptable industrial level. Furthermore, the extruded solid fuel showed excellent resistance to impact force. Regarding energy consumption, the amount of electrical energy used in the extrusion process was insignificant, ranging between 0.040-0.079 kWh/kg.

  17. Extrusão de misturas de castanha do Brasil com mandioca Extrusion of Brazil nut and cassava flour mixtures

    Directory of Open Access Journals (Sweden)

    Maria Luzenira de Souza

    2008-06-01

    Full Text Available Considerando-se que a castanha do Brasil apresenta elevado potencial nutritivo, baixo consumo no Brasil, baixo valor agregado e é um produto orgânico, além da alta produtividade, do baixo custo da mandioca e da tecnologia de extrusão termoplástica apresentarem ampla aplicabilidade e vantagens, este trabalho teve como objetivo empregar estas três variáveis, para formular misturas com castanha do Brasil e farinha de mandioca e processá-las por extrusão, visando à obtenção de produtos extrusados ricos em proteína vegetal e prontos para o consumo. Foram utilizadas torta de amêndoa de castanha do Brasil semidesengordurada e farinha de mandioca para formulações das misturas para extrusão. Aplicou-se o delineamento fatorial completo composto central (2³, com 3 variáveis independentes e a metodologia de superfície de resposta foi usada para avaliar os resultados da composição centesimal e o valor calórico, frente às variações de castanha, umidade e temperatura. Os resultados indicam que as formulações com maiores quantidades de castanha apresentam quantidades de proteínas, lipídios e cinzas mais elevadas, já as formulações com menores teores de castanha apresentam maiores percentuais de carboidratos. Os coeficientes de regressão médios do modelo estatístico para as respostas são: umidade 7,40; carboidratos 51,09; proteínas 15,34; lipídios 11,77; fibra total 9,92 e kcal 371,65. Os ensaios com menores teores de castanha e maiores de farinha apresentam-se mais expandidos e de cor clara, enquanto que aqueles com maiores teores de castanha não se expandem e têm a cor acinzentada. Conclui-se que a adição de castanha semidesengordurada à farinha de mandioca pode ser submetida à extrusão, originando um produto extrusado fonte de proteína vegetal, pronto para o consumo e que pode atender à exigência de consumidores que não utilizam proteínas de origem animal.Considering that Brazil nut presents high nutritional

  18. Extrusão dos implantes em portadores de cavidade anoftálmica Anophthalmic cavity and implant extrusion

    Directory of Open Access Journals (Sweden)

    Silvana Artioli Schellini

    2007-10-01

    Full Text Available OBJETIVO: Avaliar as características dos portadores de cavidades anoftálmicas que desenvolveram extrusão do implante. MÉTODOS: Estudo retrospectivo, observacional, tendo sido avaliados 37 portadores de cavidade anoftálmica que tiveram extrusão do implante de cavidade, na Faculdade de Medicina de Botucatu-UNESP. RESULTADOS: As extrusões ocorreram em cavidades enucleadas ou evisceradas, a maioria delas submetidas a cirurgia em decorrência de phthisis bulbi ou trauma, em geral de 1 a 2 anos após a cirurgia inicial. A deiscência precedeu a extrusão em todos os casos, tendo a extrusão ocorrido com todos os tipos de implantes empregados. CONCLUSÃO: Após a colocação de implantes de cavidade podem ocorrer complicações. A deiscência e extrusão das esferas são possibilidades que podem requerer nova intervenção cirúrgica, para a qual o paciente e o oftalmologista devem estar preparados.PURPOSE: To evaluate the characteristics of patients with anophthalmic cavity who developed sphere extrusion. METHODS: A retrospective observational study was done evaluating 37 patients with anophthalmic cavity and sphere extrusion at the "Faculdade de Medicina de Botucatu-UNESP". RESULTS: Extrusion was observed in enucleated and eviscerated cavities. The majority of the patients had the eye removed because of phthisis bulbi or trauma and the extrusion happened 1 or 2 years after the surgery. Extrusion was preceded by conjunctival dehiscence and exposure of the sphere and occurred with all used implants. CONCLUSION: Complications after orbital implant placement are a possibility. Dehiscence and sphere extrusion may happen and another surgery would be necessary. The patient and the ophthalmologist have to be prepared for this.

  19. IMPROVED PROPERTIES OF METALLOCENE-CATALYZED LINEAR LOW-DENSITY POLYETHYLENE/POLYPROPYLENE BLENDS DURING ULTRASONIC EXTRUSION

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Metallocene-catalyzed linear low-density polyethylene/polypropylene (mLLDPE/PP) blends were prepared by ultrasonic extrusion in this work. Their extrusion processing behaviors were estimated by online measured data, such as the die pressure and flow rate. Crystallization and mechanical properties of the blends were also investigated. The results show that the addition of PP improves the processing behaviors of mLLDPE, but has little effect on its mechanical properties. On the other hand, the addition of mLLDPE improves the impact strength of PP, but has little effect on its processing behavior. The processing behaviors and mechanical properties of mLLDPE/PP blends get further improved due to the presence of ultrasonic oscillation during extrusion. Compared with PP-rich blends, the apparent viscosity drop of mLLDPE-rich blends is more sensitive to ultrasonic oscillation. The ultrasonic oscillation affects the crystal nucleation, while barely the other crystalline behaviors of the blends.

  20. Extrusion cycles during dome-building eruptions

    Science.gov (United States)

    de' Michieli Vitturi, M.; Clarke, A. B.; Neri, A.; Voight, B.

    2013-06-01

    We identify and quantify controls on the timescales and magnitudes of cyclic (periodic) volcanic eruptions using the numerical model DOMEFLOW (de' Michieli Vitturi et al., 2010) which was developed by the authors for magma systems of intermediate composition. DOMEFLOW treats the magma mixture as a liquid continuum with dispersed gas bubbles and crystals in thermodynamic equilibrium with the melt and assumes a modified Poiseuille form of the viscous term for fully developed laminar flow in a conduit of cylindrical cross-section. During ascent, magma pressure decreases and water vapor exsolves and partially degasses from the melt as the melt simultaneously crystallizes, causing changes in mixture density and viscosity. Two mechanisms previously proposed to cause periodic eruption behavior have been implemented in the model and their corresponding timescales explored. The first applies a stick-slip model in which motion of a shallow solid plug is resisted by static/dynamic friction, as described in Iverson et al. (2006). For a constant magma supply rate at depth, this mechanism yields cyclic extrusion with timescales of seconds to tens of seconds with values generally depending on assumed friction coefficients. The second mechanism does not consider friction but treats the plug as a high-viscosity Newtonian fluid. During viscous resistance, pressure beneath the degassed plug can increase sufficiently to overcome dome overburden, plug weight, and viscous forces, and ultimately drive the plug from the conduit. In this second model cycle periods are on the order of hours, and decrease with increasing magma supply rate until a threshold is reached, at which point periodicity disappears and extrusion rate becomes steady (vanishingly short periods). Magma volatile content for fixed chamber pressure has little effect on cycle timescales, but increasing volatile content increases mass flow rate and cycle magnitude as defined by the difference between maximum and minimum

  1. The Favourable Choice of the Shape of Billet's Contact Surface to Quality of Extruded Aluminium Profiles

    Directory of Open Access Journals (Sweden)

    G. Skorulski

    2010-07-01

    Full Text Available The theoretical and experimental method of optimization the aluminium billet’s contact surface during extrusion have been presented inthis paper. The theoretical assumption, based on welding criteria, have been confirmed by experimental researches. The technique ofmeasurement has been shown as well. Experiments are made using plasticine as a substiute material. Some kind of different variants have been investigated. The theory and experiments have been provided to optimize the modeling shape and may help in design and technology.The theory has been tested experimentally using a plasticine as a substitute material and a plexiglass die such that the velocity fields at the surfaces could be observed and measured during plastic flow, allowing the empirical coefficients in the mathematical formulation to be estimated. On the basis of the theory and experiments an optimal billet’s contact surface was proposed.

  2. Research on semi-solid thixoforming process of AZ91D magnesium alloy brackets for generators in JH70-type motorbikes

    Institute of Scientific and Technical Information of China (English)

    WANG Kai; LIU Changming; HAN Zhaotang; CAO Jianyong; ZHANG Zonghe

    2005-01-01

    The investment on semi-solid die casting processes of AZ91D magnesium alloy brackets for generators in JH70-type motorbikes is introduced. The processes of low super-heat and cooling slope for the preparation of billets with non-dendritic microstructure, the remelting of billets for thixoforming and the parameters in the process of semi-solid thixoforming have been researched. The results show that primary billets with non-dendritical structures can be prepared by forming great amount of nuclei in melt via the process of low super heat. By optimizing the remelting process through adjusting the current of the induced equipment, semi-solid billets with a structure of spherical grains were obtained from the primary billets with non-dendritical structure. The range of 580℃ to 583℃ is the proper remelting temperatures by which the billets have an expected thixotropy and can be transferred to a die-casting machine. The optimized parameters of semi-solid forming in a die-casting machine are as follows: the area of the ingate in the die is 383.5 mm2, the speed of the pierce of the machine 5 m/s, the shot pressure of the pierce 75 MPa, and the maintenance pressure of the pierce 350 MPa.The castings of brackets for supporting generators in JH70 type motorbikes were formed by adopting the optimized processes and parameters mentioned above.

  3. Development of three-wavelength CCD image pyrometer used for the temperature field measurements of continuous casting billets

    International Nuclear Information System (INIS)

    This paper develops an imaging based three-color pyrometer for the monitoring of temperature distribution in a continuous casting billet. A novel optical device, together with an embedded electronic system, is designed to sequentially collect a dark image and three thermal images with specified wavelengths on a same monochromatic charge-coupled-device (CCD). The three thermal images provide the basis for the determination of target temperature, while the dark image is used to online eliminate the dark noise of CCD with a differential method. This image pyrometer is not only independent of target emissivity but also overcomes the dissimilarity of measuring accuracy between the micro-sensors of CCD resulted from the non-uniformity of pixels’ intensity response and the vignetting of optical system. Furthermore, a precise two-color temperature field measuring model on the CCD pyrometer is established, based on which a self-adaptive light-integration mechanism is presented. Compared with the traditional fixed light-integration method, the measuring range of the pyrometer is greatly extended and its sensitivity in low temperature segment is improved. The test results in a steel factory demonstrate that the pyrometer is capable of meeting the requirement of surface temperature measurements about casting billets. Reliability and accuracy of measurement results are also discussed herein

  4. Efficient heating of billets with regard to reinforcing steel production; Effiziente Knueppelerwaermung fuer die Produktion von Bewehrungsstahl

    Energy Technology Data Exchange (ETDEWEB)

    Hentschel, L.; Wolter, K.C. [Badische Stahlwerke, Kehl (Germany); Laviosa, V. [Techint - Compagnia Tecnica Internationale (Italy); Pastoino, B. [Techint ITALIMPIANTI Deutschland GmbH (Germany)

    2004-12-01

    The mass-production of reinforcing steel for the construction industry is in Germany a challenge with regard to the energy costs and environmental aspects for every producer. The Badischen Stahlwerke are with almost 2 Mill. Tons finished product cast from 100% scrap one of the most productive Ministeelplants worldwide. The production line includes the reheating of cast billets using a heating furnace. Due to the usage of hot billets directly from the casting unit it is possible to save a high amount of energy and increase the production. In conjunction with the erection of a new pusher furnace at Badische Stahlwerke through Techint-ITALIMPIANTI in 2001 these potentials will be shown. With the gradually replacement of the wire rod technology and the actual burner load of the furnace using hot charging there is enough headroom in order to increase the production without neglecting environmental aspects. The manufacturer gives with regard to lower NO{sub x} emissions perspectives to further reduce the emissions by a high degree to ensure the possibility of reinforcing steel production in Germany although the environmental restrictions are intensified. (orig.)

  5. 钢坯试样铣磨床总体方案的创新设计%Innovative design for overall Scheme of milling-grinding machine for billet steel sample

    Institute of Scientific and Technical Information of China (English)

    薛会民; 欧阳晶晖

    2011-01-01

    It expounds the innovative design for overall scheme of the milling-grinding machineAc-cording to the processing requirements of high efficiency and high surface quality for billet test sample,the principle scheme of machine tool was proposed based on combined innovation, which achieves a composite process of milling and grindingJn addition the grinding adopts modern belt grinding.The motion scheme of the machine tool was designed through analyzing movement functionsAs for general structure of the machine tool fixed beam gantry frame structure is adopted based on structural variation.The result indicates that the overall scheme innovation realizes the uniqueness design of the machine tool,which has good performance and can well satisfy the processing requirements of billet steel sample.%阐述了铣磨床总体方案的创新设计,针对钢坯检测试样高效率、高表面质量的加工要求,采用组合创新的方法,提出了在同一机床上实现铣削、磨削复合加工的工艺原理方案,并且机床的磨削加工采用了现代砂带磨削.通过分析机床的各种运动功能,设计了机床的运动方案.对于机床的总体结构布局,采用结构变异的方法,确定其为定梁龙门式框架结构.结果表明,通过总体方案的创新,实现了机床的独特性设计,所设计机床性能优良,很好地满足了钢坯检测试样的加工要求.

  6. Soft magnetic composites manufactured by warm co-extrusion of bulk metallic glass and steel powders

    International Nuclear Information System (INIS)

    Soft magnetic composites of Fe-based bulk metallic glass and low-alloy steel have been manufactured by warm co-extrusion of precursor powders at temperatures within the supercooled liquid region of the glass. Composites were manufactured with amorphous volume fractions of 75%, 67%, and 100%. Full consolidation of the constituent powders was observed with the bulk metallic glass remaining substantially amorphous. The composite electrical resistivity was observed to be anisotropic with a resistivity of 79 μΩ cm measured transverse to the extrusion axis in a sample with 75% amorphous volume fraction. A 0-3 connectivity pattern with the low-resistivity steel phase embedded in a 3-dimensionally connected high-resistivity bulk metallic glass phase was observed with scanning electron microscopy. This confirms that the flow characteristics of the bulk metallic glass and the steel powders were comparable during extrusion at these temperatures. The saturation magnetization of 1.3 T was consistent with the volume weighted average of the saturation magnetization of the two phases. A relatively high quasistatic coercivity of 8 Oe was measured and is likely due to slight crystallization of the bulk metallic glass as well as domain wall pinning at prior particle boundaries. Careful control of the thermal environment during the extrusion process is required to minimize glass crystallization and achieve the desired balance of magnetic and electrical properties.

  7. Soft magnetic composites manufactured by warm co-extrusion of bulk metallic glass and steel powders

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Francis; Raber, Thomas R.; Zabala, Robert J.; Buresh, Steve J.; Tanico, Brian [GE Global Research, Ceramic and Metallurgy Technologies, One Research Circle, Niskayuna, New York 12309 (United States)

    2013-05-07

    Soft magnetic composites of Fe-based bulk metallic glass and low-alloy steel have been manufactured by warm co-extrusion of precursor powders at temperatures within the supercooled liquid region of the glass. Composites were manufactured with amorphous volume fractions of 75%, 67%, and 100%. Full consolidation of the constituent powders was observed with the bulk metallic glass remaining substantially amorphous. The composite electrical resistivity was observed to be anisotropic with a resistivity of 79 {mu}{Omega} cm measured transverse to the extrusion axis in a sample with 75% amorphous volume fraction. A 0-3 connectivity pattern with the low-resistivity steel phase embedded in a 3-dimensionally connected high-resistivity bulk metallic glass phase was observed with scanning electron microscopy. This confirms that the flow characteristics of the bulk metallic glass and the steel powders were comparable during extrusion at these temperatures. The saturation magnetization of 1.3 T was consistent with the volume weighted average of the saturation magnetization of the two phases. A relatively high quasistatic coercivity of 8 Oe was measured and is likely due to slight crystallization of the bulk metallic glass as well as domain wall pinning at prior particle boundaries. Careful control of the thermal environment during the extrusion process is required to minimize glass crystallization and achieve the desired balance of magnetic and electrical properties.

  8. Molding of Aluminum Foams by Using Hot Powder Extrusion

    Directory of Open Access Journals (Sweden)

    Yoshitaka Tanino

    2012-06-01

    Full Text Available In order to form aluminum foams directly from powder, a combined process of hot powder extrusion and molding is proposed. Aluminum powder mixed with a foaming agent is extruded into the mold through the die heated to a temperature higher than the melting point, and the mold is filled with the aluminum foam. When a stainless steel pipe is used for a simple mold, an aluminum foam bar is obtained of which the relative density varies between 0.2 and 0.3. The molding of aluminum foam by using three types of mold shape shows the influence of gravity and friction. The effect of gravity is significant when a large step exists at the connection between the mold inlet and the die outlet, and friction is dominant in cases where foam is mold in a narrow space.

  9. Scalable Approach for Extrusion and Perfusion of Tubular, Heterotypic Biomaterials

    Science.gov (United States)

    Jeronimo, Mark David

    Soft material tubes are critical in the vasculature of mammalian tissues, forming networks of blood vessels and airways. Homogeneous and heterogeneous hydrogel tubes were extruded in a one-step process using a three layer microfluidic device. Co-axial cylindrical flow of crosslinking solutions and an alginate matrix is generated by a radial arrangement of microfluidic channels at the device's vertical extrusion outlet. The flow is confined and begins a sol-gel transition immediately as it extrudes at velocities upwards of 4 mm/s. This approach allows for predictive control over the dimensions of the rapidly formed tubular structures for outer diameters from 600 microm to 3 mm. A second microfluidic device hosts tube segments for controlled perfusion and pressurization using a reversible vacuum seal. On-chip tube deflection is observed and modeled as a measure of material compliance and circumferential elasticity. I anticipate applications of these devices for perfusion cell culture of cell-laden hydrogel tubes.

  10. A Review of Dynamic Models of Hot-Melt Extrusion

    Directory of Open Access Journals (Sweden)

    Jonathan Grimard

    2016-06-01

    Full Text Available Hot-melt extrusion is commonly applied for forming products, ranging from metals to plastics, rubber and clay composites. It is also increasingly used for the production of pharmaceuticals, such as granules, pellets and tablets. In this context, mathematical modeling plays an important role to determine the best process operating conditions, but also to possibly develop software sensors or controllers. The early models were essentially black-box and relied on the measurement of the residence time distribution. Current models involve mass, energy and momentum balances and consists of (partial differential equations. This paper presents a literature review of a range of existing models. A common case study is considered to illustrate the predictive capability of the main candidate models, programmed in a simulation environment (e.g., MATLAB. Finally, a comprehensive distributed parameter model capturing the main phenomena is proposed.

  11. The effect of extrusion on the functional components and in vitro lycopene bioaccessibility of tomato pulp added corn extrudates.

    Science.gov (United States)

    Tonyali, Bade; Sensoy, Ilkay; Karakaya, Sibel

    2016-02-01

    The effect of processing on functional ingredients and their in vitro bioaccessibility should be investigated to develop better food products. Tomato pulp was added as a functional ingredient to extrudates. The effects of extrusion on the functional properties of the extrudates and the in vitro bioaccessibility of lycopene were investigated. Two different temperature sets were applied during extrusion: 80 °C, 90 °C, 100 °C and 130 °C and 80 °C, 100 °C, 130 °C and 160 °C. Screw speed and feed rate were kept constant at 225 rpm and 36 ± 1 g min(-1), respectively. The feed moisture content was adjusted to 30 ± 1% by mixing the tomato pulp to the corn grit. Antioxidant activity and the total phenolic content decreased after the extrusion process. High performance liquid chromatography (HPLC) analysis indicated that the lycopene content decreased after the extrusion process when feed and extrudates were compared. In vitro bioaccessibility of lycopene for the extruded samples with 160 °C last zone treatment temperature was higher than the feed and extruded samples with 130 °C last zone treatment temperature. The results indicate that extrusion affects the food matrix and the release of functional components. PMID:26674172

  12. Prediction of Microstructure Evolution in Hot Backward Extrusion of Ti-6Al-4V Alloy

    Directory of Open Access Journals (Sweden)

    Jong-Taek Yeom

    2012-01-01

    Full Text Available Microstructure evolution of Ti-6Al-4V alloy during hot backward extrusion process was simulated with the combined approaches of finite element method (FEM and microstructure prediction model. From experimental analysis, it can be found that the change of microstructure during hot forming process of titanium alloy has a close relation to α/β phase transformation and grain growth behaviour. A microstructure prediction model was established by considering the change of volume fractions and grain size of both phases varying with process variables and then implemented into the user-defined subroutine of FEM analysis. In order to demonstrate the reliability of the model, the volume fraction and grain size of primary α phase during the hot backward extrusion process of Ti-6Al-4V alloy were simulated. The simulation results were compared with the experimental ones.

  13. Effect of conventional and extrusion pelleting on in situ ruminal degradability of starch, protein, and fibre in cattle

    DEFF Research Database (Denmark)

    Razzaghi, Ali; Larsen, Mogens; Weisbjerg, Martin Riis

    2016-01-01

    +50% sugar beet pulp (SBP), or 50% maize+50% SBP. Meals were pelleted by either conventional pelleting, or by cooking extrusion using two distinct settings giving pellets with either high density (HD) or low density (LD). Ruminal degradation of starch, crude protein (CP) and NDF, and intestinal......>Pelleting>Meal). In contradiction, ESD for pure wheat and wheat mixtures was reduced, though differences were minor. Conventional pelleting reduced the effective protein degradability (EPD) for pure wheat, but extrusion did not further affect the EPD. In contrast, the most intense processing with extrusion LD increased EPD...... for pure maize. Processing reduced EPD in both cereal+SBM mixtures, and further, the most intense processing with extruding LD led to the lowest EPD in cereal+SBM mixtures. In contrast, extruding increased EPD in both cereal+SBP mixtures as compared with meal and pelleting, but extruding with steam...

  14. Experimental Study and Finite Element Polycrystal Model Simulation of the Cold Rolling Textures in a Powder Metallurgy Processed Pure Aluminum Plate

    Institute of Scientific and Technical Information of China (English)

    Liqing CHEN; Naoyuki Kanetake

    2005-01-01

    Ingot metallurgy (IM) aluminum has long been the subject and attracted the attention of many metallurgists and textural researchers of materials. Due to the introduction of large amounts of ex situ interfaces, however, the textures in powder metallurgy (PM) processed aluminum has been rarely reported. In this article, a pure aluminum plate was prepared via PM route. The starting billet was first produced with uni-axially cold compaction and flat hot-extrusion and then followed by cold rolling processes. The hot-extruded and cold rolling deformation textures of the pure PM aluminum at 50%, 80% and 90% cold rolling reductions were studied by orientation distribution functions (ODFs) analysis. The finite element polycrystal model (FEPM) was finally utilized to simulate the cold rolling textural evolution at various stages of cold rolling. In FEPM simulation, the initial hot-extruded textures were taken into account as inputs. The results showed that typical β-fiber texture formed in pure PM aluminum with the cold rolling reduction increased till 80%, and there was not much change after excessive cold rolling deformation.Homogeneous slip is not the only deformation mode in PM processed pure aluminum plate at over 80% cold rolling reduction. The experimental results were qualitatively in good agreement with the simulated ones.

  15. 75 FR 34482 - Certain Aluminum Extrusions From China

    Science.gov (United States)

    2010-06-17

    ... Commission, Washington, DC, and by publishing the notice in the Federal Register of April 6, 2010 (75 FR... COMMISSION Certain Aluminum Extrusions From China Determinations On the basis of the record \\1\\ developed in... reason of imports from China of certain aluminum extrusions, provided for in subheadings 7604.21,...

  16. 76 FR 29007 - Certain Aluminum Extrusions From China

    Science.gov (United States)

    2011-05-19

    ... in the Federal Register on December 22, 2010 (75 FR 80527). The hearing was held in Washington, DC... COMMISSION Certain Aluminum Extrusions From China Determinations On the basis of the record \\1\\ developed in... certain aluminum extrusions from ] China other than finished heat sinks, provided for in subheadings...

  17. Fate of the fusarium mycotoxins deoxynivalenol, nivalenol and zearalenone during extrusion of wholemeal wheat grain

    OpenAIRE

    Scudamore, Keith; Guy, Robin C, E; Kelleher, Brian; MacDonald, Susan

    2008-01-01

    Abstract Deoxynivalenol in cereals and cereal products is controlled in the European Community by recent legislation with the objective of minimizing consumer exposure to this mycotoxin. Relatively few studies have examined the losses of fusarium mycotoxins during processing and whether this is accurately reflected by the processing factors that have been used. The behaviour of deoxynivalenol, nivalenol and zearalenone during extrusion of naturally contaminated wholemeal wheat flou...

  18. Abl suppresses cell extrusion and intercalation during epithelium folding.

    Science.gov (United States)

    Jodoin, Jeanne N; Martin, Adam C

    2016-09-15

    Tissue morphogenesis requires control over cell shape changes and rearrangements. In the Drosophila mesoderm, linked epithelial cells apically constrict, without cell extrusion or intercalation, to fold the epithelium into a tube that will then undergo epithelial-to-mesenchymal transition (EMT). Apical constriction drives tissue folding or cell extrusion in different contexts, but the mechanisms that dictate the specific outcomes are poorly understood. Using live imaging, we found that Abelson (Abl) tyrosine kinase depletion causes apically constricting cells to undergo aberrant basal cell extrusion and cell intercalation. abl depletion disrupted apical-basal polarity and adherens junction organization in mesoderm cells, suggesting that extruding cells undergo premature EMT. The polarity loss was associated with abnormal basolateral contractile actomyosin and Enabled (Ena) accumulation. Depletion of the Abl effector Enabled (Ena) in abl-depleted embryos suppressed the abl phenotype, consistent with cell extrusion resulting from misregulated ena Our work provides new insight into how Abl loss and Ena misregulation promote cell extrusion and EMT.

  19. Preparation of chalcogenide glass fiber using an improved extrusion method

    Science.gov (United States)

    Jiang, Chen; Wang, Xunsi; Zhu, Minming; Xu, Huijuan; Nie, Qiuhua; Dai, Shixun; Tao, Guangming; Shen, Xiang; Cheng, Ci; Zhu, Qingde; Liao, Fangxing; Zhang, Peiquan; Zhang, Peiqing; Liu, Zijun; Zhang, Xianghua

    2016-05-01

    We developed the extrusion method to prepare arsenic-free chalcogenide glass fibers with glass cladding. By using the double nested extrusion molds and the corresponding isolated stacked extrusion method, the utilization rate of glass materials was greatly improved compared with the conventional extrusion method. Fiber preforms with optimal stability of core/cladding ratio throughout the 160 mm length were prepared using the developed extrusion method. Typical fiber structure defects between the core/cladding interface, such as bubbles, cracks, and core diameter variation, were effectively eliminated. Ge-Sb-Se/S chalcogenide glasses were used to form a core/cladding pair and fibers with core/cladding structure were prepared by thermally drawing the extruded preforms. The transmission loss, fiber bending loss, and other optical characters of the fibers were also investigated.

  20. Application of Twin Screw Extrusion in the Manufacture of Cocrystals, Part I: Four Case Studies

    Directory of Open Access Journals (Sweden)

    Karthik Nagapudi

    2011-08-01

    Full Text Available The application of twin screw extrusion (TSE as a scalable and green process for the manufacture of cocrystals was investigated. Four model cocrystal forming systems, Caffeine-Oxalic acid, Nicotinamide-trans cinnamic acid, Carbamazepine-Saccharin, and Theophylline-Citric acid, were selected for the study. The parameters of the extrusion process that influenced cocrystal formation were examined. TSE was found to be an effective method to make cocrystals for all four systems studied. It was demonstrated that temperature and extent of mixing in the extruder were the primary process parameters that influenced extent of conversion to the cocrystal in neat TSE experiments. In addition to neat extrusion, liquid-assisted TSE was also demonstrated for the first time as a viable process for making cocrystals. Notably, the use of catalytic amount of benign solvents led to a lowering of processing temperatures required to form the cocrystal in the extruder. TSE should be considered as an efficient, scalable, and environmentally friendly process for the manufacture of cocrystals with little to no solvent requirements.

  1. Effect of Grain Refinement on Structure Evolution, “Floating” Grains, and Centerline Macrosegregation in Direct-Chill Cast AA2024 Alloy Billets

    NARCIS (Netherlands)

    Nadella, R.; Eskin, D.G.; Katgerman, L.

    2007-01-01

    Direct-chill (DC) cast billets 192 mm in diameter of an Al-Cu-Mg alloy were examined in detail with the aim to reveal the effects of grain refining (GR) and casting speed on structure, “floating” grains, and centerline macrosegregation. Experimental results show that grain size and dendrite arm spac

  2. Cold-Cracking Assessment in AA7050 Billets during Direct-Chill Casting by Thermomechanical Simulation of Residual Thermal Stresses and Application of Fracture Mechanics

    NARCIS (Netherlands)

    Lalpoor, M.; Eskin, D.G.; Katgerman, L.

    2009-01-01

    Thermally induced strains and stresses developed during direct-chill (DC) semicontinuous casting of high strength aluminum alloys can result in formation of micro-cracks in different locations of the billet. Rapid propagation of such micro-cracks in tensile thermal stress fields can lead to catastro

  3. Effect of Hot Extrusion on Interfacial Microstructure and Tensile Properties of SiCp/2009A1 Composites Fabricated at Different Hot Pressing Temperatures

    Institute of Scientific and Technical Information of China (English)

    Peng Jin; Bolu Xiao; Quanzhao Wang; Zongyi Ma; Yue Liu; Shu Li

    2011-01-01

    The effects of hot extrusion on the interfacial microstructures and tensile properties of 15 vol% SiCp/2009Alcomposites fabricated at different hot pressing temperatures were investigated. After hot extrusion, the relative density of the composites increased, the SiC particle distribution became more uniform, and the SiC particles tended to align along the extrusion direction. Furthermore, the interface bonding was improved after hot extrusion; however, the extrusion exerted no obvious effect on the interfacial reaction products formed during sintering process. Tensile tests indicated that the mechanical properties of the composites were improved significantly after extrusion. Fractography revealed that the fracture mechanism of the extruded composites fabricated at the hot pressing temperatures below 540℃ was mainly the interracial debonding. For the extruded composites fabricated at 560-600℃, the fracture was the matrix ductile fracture and the SiC particle fracture.When the composites were hot pressed at or above 620℃, after extrusion, the fracture mechanism of the composites was the matrix ductile fracture, the interface cracking and the SiC particle fracture.

  4. 热塑挤压操作参数对低值水产蛋白组织化产品功能特性的影响%Effect of Extrusion Cooking Process Parameter on Functional Properties of Texturized Products in Low Value Aquatic Protein

    Institute of Scientific and Technical Information of China (English)

    杨涛; 辛建美; 徐青; 罗红宇

    2011-01-01

    The waste scrap from the North Pacific squid processing was used as raw material. Effect of extrusion process parameters on the functional properties of extruded squid protein using a twin screw extruder was studied using Response Surface Methodology. As input variables, twin extrusion cooking running parameters examined were feed moisture, barrel temperature and screw speed. Meanwhile, as output variables, functional properties of the resultant extrudates included water holding capacity and oil holding capacity. Results showed that feed moisture, screw speed and interaction of feed moisture and barrel temperature had all significant influence on both water holding capacity and oil holding capacity. Interaction of feed moisture and screw speed had just significant influence on water holding capacity. Polynomial regression equations of process variables with two functional properties were obtained with R2=0.890 and R2=0.979, respectively. Both of two regression equations were highly credible.%以北太平洋鱿鱼加工边角料为原料,采用双螺杆挤压技术及响应面分析方法研究主要操作参数——物料湿度、机筒温度和螺杆转速对鱿鱼蛋白挤出物的持水性和持油性的影响,分别建立挤出物持水性指数、持油性指数与操作参数的回归拟合方程.试验结果表明,物料湿度、螺杆转速以及物料湿度和机筒温度的交互作用对挤出物持水性和持油性均有显著影响,物料湿度与螺杆转速的交互作用仅对挤出物持水性有显著影响:持水性、持油性指数与操作参数的回归拟合方程的相关系数R2分别是0.890和0.979,表明拟合的统计模型可信度较高.

  5. 基于GA-BP混合算法的液固挤压工艺组合参数逆向设计%Reversing design on combined parameters of liquid-solid extrusion process based on the predictive model using hybrid GA-BP algorithm

    Institute of Scientific and Technical Information of China (English)

    苏力争; 齐乐华; 周计明; 王振军; 李贺军

    2009-01-01

    为改善液周挤压复合材料成形过程中金属的流动均匀性,减少制件的内部损伤缺陷,基于人工神经网络及遗传算法,采用改进的混合GA-BP算法建立了设计参数与控制目标的非线性映射关系.通过对样本集的学习,初步建立了液固挤压工艺组合参数知识库,将网络预测值与实验值进行对比,其最大相对误差不超过0.79%,说明采用GA-BP混合算法建立的预测模型具有较高的预测精度.利用所建立的预测模型,分析了模具参数和工艺参数组合对制件变形均匀性的耦合作用,为液固挤压工艺的综合设计与优化提供了理论依据.%In order to control deformation uniformity of composite in the forming process of liquid-solid extrusion and reduce inner damaging defects of products. Based on artificial neural network (ANN) technique and genetic algorithm (GA), the nonlinear mapping relation between design variables and objective function was proposed and established by the modified GA-BP algorithm. The simulation results of FEM called virtual samples were selected as the network's training samples. By training the sample, the knowledge base of the muti-parameters for the liquid-solid extrusion was set up. Comparing with the experimental results, the largest relative error between the actual output value of the network and the experimental data is 0. 79 percent It proves that the forecast model established using GA-BP hybrid algorithm has a higher accuracy. The influences of main process parameters and structures parameters had been studied on the deformation uniformity using the predictive function of the model. They are good instructions for the design and optimization of the liquid-solid extruding composites process.

  6. Mechanical characteristic of flowing solidification under the extrusion for the mixture of the liquid aluminum with sillimanite particles

    Energy Technology Data Exchange (ETDEWEB)

    Wei Chen [Academy of Armored Force Engineering (China); Jiangsu Fasten Block Corp. (China); Changqing Sun; Yunliang Li [Academy of Armored Force Engineering (China)

    2005-07-01

    According to the theory of liquid metal forging and liquid metal extrusion, a new kind of fabricating method for particles reinforced metallic matrix composite was put forward by author. In this paper, the extrusion process to semisolid thick liquid after the mixture was studied by means of the theoretical analysis and experimental methods. Mechanical characteristics of solidification during flowing and plastic deformation during solidification of the composite were found. So the base was built up for selecting technology parameters and for building a stable process. (orig.)

  7. Dynamic simulation on effect of flame arrangement on thermal process of regenerative reheating furnace

    Institute of Scientific and Technical Information of China (English)

    OU Jian-ping; MA Ai-chun; ZHAN Shu-hua; ZHOU Jie-min; XIAO Ze-qiang

    2007-01-01

    By analyzing the characteristics of combustion and billet heating process, a 3-D transient computer fluid dynamic simulation system based on commercial software CFX4.3 and some self-programmed codes were developed to simulate the thermal process in a continuous heating furnace using high temperature air combustion technology. The effects of different switching modes on injection entrancement of multi burners, combustion and billet heating process in furnace were analyzed numerically, and the computational results were compared with on-site measurement, which verified the practicability of this numerical simulation system.The results indicate that the flow pattern and distribution of temperature in regenerative reheating furnace with partial same-side-switching combustion mode are favorable to satisfy the high quality requirements of reheating, in which the terminal heating temperature of billets is more than 1 460 K and the temperature difference between two nodes is not more than 10 K. But since the surface average temperature of billets apart from heating zone is only about 1 350 K and continued heating is needed in soaking zone, the design and operation of current state are still needed to be optimized to improve the temperature schedule of billet heating. The distribution of velocity and temperature in regenerative reheating furnace with same-side-switching combustion mode cannot satisfy the even and fast heating process. The terminal heating temperature of billets is lower than that of the former case by 30 K. The distribution of flow and temperature can be improved by using cross-switching combustion mode, whose terminal temperature of billets is about 1 470 K with small temperature difference within 10 K.

  8. Thermal Stabilization study of polyacrylonitrile fiber obtained by extrusion

    Directory of Open Access Journals (Sweden)

    Robson Fleming Ribeiro

    2015-12-01

    Full Text Available A low cost and environmental friendly extrusion process of the Polyacrylonitrile (PAN polymer was viabilized by using the 1,2,3-propanetriol (glycerol as a plasticizer. The characterization of the fibers obtained by this process was the object of study in the present work. The PAN fibers were heat treated in the range of 200 °C to 300 °C, which is the temperature range related to the stabilization/oxidation step. This is a limiting phase during the carbon fiber processing. The characterization of the fibers was made using infrared spectroscopy, thermal analysis and microscopy. TGA revealed that the degradation of the extruded PAN co-VA fibers between 250 °C and 350 °C, corresponded to a 9% weight loss to samples analyzed under oxidizing atmosphere and 18% when the samples were analyzed under inert atmosphere. DSC showed that the exothermic reactions on the extruded PAN co-VA fibers under oxidizing synthetic air was broader and the cyclization started at a lower temperature compared under inert atmosphere. Furthermore, FT-IR analysis correlated with thermal anlysis showed that the stabilization/oxidation process of the extruded PAN fiber were coherent with other works that used PAN fibers obtained by other spinning processes.

  9. Thermal shrinkage of thermoplastic sheets obtained by extrusion and calendering

    Energy Technology Data Exchange (ETDEWEB)

    Vdorenko, P.K.; Urasovskii, V.N.; Voskresenskii, A.M.

    1983-01-01

    The authors carried out experimental and theoretical investigations of the effect of technological process parameters on the thermal shrinkage of thermoplastic sheets obtained by extrusion and calendering. Conditions were studied for processing the material ABS-3A and high-density polyethylene 4020-EK. The main purpose of the investigation was to determine the interrelation between processing conditions and elastic deformations in the sheet, which were fixed by cooling before the take-in device and which were manifested in the thermal shrinkage of specimens taken from the sheet. The experimental data were treated by statistical generalization in the form of a regression model. The model with shrinkage coefficients can be used to select efficient processing conditions. In addition, the shrinkage value is preassigned in accordance with the permissible level. Further, a variant corresponding to the greatest productivity of the press is found by calculation among thevarious combinations of parameters of the technological conditions. In using the regression model, it is convenient to orient oneself toward the independent contribution of the first two factors, the tensile stress of the sheet and the processing velocity, to the response function. This procedure may also be used for other thermoplastic materials.

  10. Convergence and extrusion are required for normal fusion of the mammalian secondary palate.

    Directory of Open Access Journals (Sweden)

    Seungil Kim

    2015-04-01

    Full Text Available The fusion of two distinct prominences into one continuous structure is common during development and typically requires integration of two epithelia and subsequent removal of that intervening epithelium. Using confocal live imaging, we directly observed the cellular processes underlying tissue fusion, using the secondary palatal shelves as a model. We find that convergence of a multi-layered epithelium into a single-layer epithelium is an essential early step, driven by cell intercalation, and is concurrent to orthogonal cell displacement and epithelial cell extrusion. Functional studies in mice indicate that this process requires an actomyosin contractility pathway involving Rho kinase (ROCK and myosin light chain kinase (MLCK, culminating in the activation of non-muscle myosin IIA (NMIIA. Together, these data indicate that actomyosin contractility drives cell intercalation and cell extrusion during palate fusion and suggest a general mechanism for tissue fusion in development.

  11. Powder metallurgy processing of high strength turbine disk alloys

    Science.gov (United States)

    Evans, D. J.

    1976-01-01

    Using vacuum-atomized AF2-1DA and Mar-M432 powders, full-scale gas turbine engine disks were fabricated by hot isostatically pressing (HIP) billets which were then isothermally forged using the Pratt & Whitney Aircraft GATORIZING forging process. While a sound forging was produced in the AF2-1DA, a container leak had occurred in the Mar-M432 billet during HIP. This resulted in billet cracking during forging. In-process control procedures were developed to identify such leaks. The AF2-1DA forging was heat treated and metallographic and mechanical property evaluation was performed. Mechanical properties exceeded those of Astroloy, one of the highest temperature capability turbine disk alloys presently used.

  12. Process on cold crucible electromagnetic casting for titanium alloy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The parameters and factors that influence the surface quality and macrostructure of titanium alloy with reactive properties under liquid state were studied experimentally using a cold crucible electromagnetic casting method. The variations in the process parameters have great impact on the surface quality and macrostructure of cast billets. Billets with crack free and smooth surfaces as well as directional solidified primary structures were obtained after the selection of optimized process parameters. The formation mechanisms of defects such as cracks and non-directional structural morphology were interpreted briefly. Finally, the casting of billets with good outer qualities and inner column grains has been attained successfully, which in turn gives a solid foundation for further development of the technology.

  13. Process on cold crucible electromagnetic casting for titanium alloy

    Directory of Open Access Journals (Sweden)

    CHEN Rui-run

    2007-08-01

    Full Text Available The parameters and factors that influence the surface quality and macrostructure of titanium alloy with reactive properties under liquid state were studied experimentally using a cold crucible electromagnetic casting method. The variations in the process parameters have great impact on the surface quality and macrostructure of cast billets. Billets with crack free and smooth surfaces as well as directional solidified primary structures were obtained after the selection of optimized process parameters. The formation mechanisms of defects such as cracks and non-directional structural morphology were interpreted briefly. Finally, the casting of billets with good outer qualities and inner column grains has been attained successfully, which in turn gives a solid foundation for further development of the technology.

  14. Orthodontic extrusion in the transitional dentition: a simple technique.

    LENUS (Irish Health Repository)

    Darby, Laura J

    2009-11-01

    Extrusion of teeth may be necessary in cases of delayed eruption, primary retention, traumatically intruded teeth, or subgingivally fractured teeth. Removable appliances are advantageous, as anchorage is not as tooth-dependant as in the case of fixed appliances. They are cost-effective, operator friendly, and a valuable treatment option to consider in cases where extrusion of anterior teeth in the transitional dentition is necessary. The purpose of this paper was to describe a simple, cost-effective technique using a removable appliance for extrusion of incisors in the transitional dentition.

  15. EXTRUSION DIE CAE OF THE STEEL REINFORCED PLASTIC PIPE

    Institute of Scientific and Technical Information of China (English)

    W.Q. Ma; H.Y. Sun; D.C. Kang; K.D. Zhao

    2004-01-01

    The steel reinforced plastic pipe is a new kind of pressure pipe. It is made up with steel wires and plastic. Because reinforced skeleton of the steel wire increase the complexity of plastic flow during the extrusion phase, the traditional design criteria of extrusion die is not suitable. The study on extrusion die of the kind of pipe is very important step in produce development. Using finite element (FE) method in this paper, the flow rule of molten plastic inside the die has been predicted and a group of optimal structural parameters was obtained. These results are helpful for reducing the design cycle and improve the quality of the final product.

  16. Study On Extrusion Technological Parameters Of Brown Rice

    Institute of Scientific and Technical Information of China (English)

    Zhu Yongyi; Zhou Xianqing; Ling Lizhong

    2001-01-01

    Extrusion is an efficient measure to improve the texture and physic-s of brown rice. The polynomial degree two model of extrusion parameters and gelatinized degree, water absorption index, water soluble index and moisture content of extruded matter was obtained by methods of single factor and response surface methodology, R2=0.9649, 0.8745, 0.9079, 0.8677. The optimal parameters of brown rice extrusion were figured out as follows:moisture nrice, 11.42%, speed of screw, 30rpm, feeding speed, and 20rpm.

  17. Chain extension of poly (ethylene terephthalate) by reactive extrusion with secondary stabilizer

    OpenAIRE

    Breno Heins Bimestre; Clodoaldo Saron

    2012-01-01

    Poly(ethylene tereftalate) (PET) is a polymer highly susceptible to the hydrolytic reactions that occur during applications and mainly in thermomechanical processing. These reactions lead to the decrease of molecular weight of the polymer, limiting the recycling number of the material. The reactive extrusion of the PET in presence of chain extenders is an alternative to recover mechanical and rheological properties that were depreciated by the polymer degradation. In this study, PET wastes fr...

  18. Comparison of melt extrusion and thermokinetic mixing methods in poly(ethylene terephthalate)/montmorillonite nanocomposites

    OpenAIRE

    Özen, İlhan; Ozen, Ilhan; İnceoğlu, Funda; Inceoglu, Funda; Acatay, Kazım; Acatay, Kazim; Menceloğlu, Yusuf Z.; Menceloglu, Yusuf Z.

    2012-01-01

    The scope of this study consists in studying the effects of processing type on thermal stability of poly(ethylene terephthalate) (PET) and its nanocomposites prepared with organically modified clays. To achieve this goal, an intercalating agent was synthesized and montmorillonite type of clay modified with this intercalating agent was mixed with the PET by using melt extrusion and high-shear thermokinetic mixing method. According to the results, manganese in the raw claythough chemically boun...

  19. Hot extrusion for Al-Si-(Fe, Cu) hyper-eutectic cast alloys

    OpenAIRE

    Yokoyama, Hisanaga; Umezawa, Osamu; Nagai, Kotobu; Kokubo, Kunio

    1999-01-01

    For hyper-eutectic Al-Si-(Fe, Cu) cast materials in large scale ingots, we have studied microstructural modification by thermomechanical treatment to produce a heavily deformable material. Cast materials contained coarse primary Si crystals in a few hundred micron diameter or acicular intermetallic compound in several hundred micron length. Even by multiple-step cold-rolling, sample fracture of the cast alloys occurred with more extrusion step to the cast materials. A novel process, repeated ...

  20. Forming the structure and properties of hybrid coatings on reversible rotating extrusion dies

    OpenAIRE

    K. Lukaszkowicz

    2012-01-01

    Purpose: The purpose of this monograph was to develop the methodology of formation, classification of properties and analysis of the structure of the surface layers, particularly the zone connecting the core and the coating and between the single layers created on the working surfaces of dies for the plastic formation on non-ferrous metals, with particular consideration to the specific nature of the extrusion process with reversibly rotating die (the KOBO method).Design/methodology/approach: ...

  1. Application of Electrostatic Extrusion – Flavour Encapsulation and Controlled Release

    OpenAIRE

    Branko Bugarski; Viktor Nedovic; Bojana Obradovic; Jasna Djonlagic; Nevenka Rajic; Verica Manojlovic

    2008-01-01

    The subject of this study was the development of flavour alginate formulationsaimed for thermally processed foods. Ethyl vanilline was used as the model flavourcompound. Electrostatic extrusion was applied for the encapsulation of ethyl vanilline inalginate gel microbeads. The obtained microbeads with approx. 10 % w/w of ethylvanilline encapsulated in about 2 % w/w alginate were uniformly sized spheres of about450 μm. Chemical characterization by H-NMR spectroscopy revealed that the algina...

  2. Effects of hot extrusion and annealing treatment on microstructures,properties and texture of AZ31 Mg alloy

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui; YAN Yun-qi; WENG Wen-ping; ZHONG Hao; CHEN Qi

    2006-01-01

    Effects of extrusion deformation and heat treatment on microstructures, mechanical properties and texture of AZ31 Mg alloy were investigated.The results show that the microstructures of as-cast AZ31 alloy are markedly refined after hot extruding, the average grain size is about 25 μm and strong fiber texture exists in the extruded AZ31 alloy. The mechanical properties are improved obviously. The grain size is somewhat inhomogeneous and strip structure emerges along the extrusion direction due to incomplete dynamic recrystallization during the extrusion process. With increasing annealing temperature, the small grain grows up and turns into equiaxed grain, and the texture is weakened with the visible growing up of grains.

  3. Microstructure evolution of semi-solid 2024 alloy during two-step reheating process

    Institute of Scientific and Technical Information of China (English)

    WANG Shun-cheng; LI Yuan-yuan; CHEN Wei-ping; ZHENG Xiao-ping

    2008-01-01

    A two-step reheating process was proposed and applied to perform reheating experiments on the semi-solid 2024 alloy billet. In this process, the semi-solid billet was firstly heated over liquidus temperature and then isothermally held at solid-liquid zone temperature. Microstructure evolution of the semi-solid billet during two-step reheating was studied by optical microscope and compared with that during isothermal reheating. The results show that the remelting rate of the semi-solid billet during two-step reheating is faster than that during isothermal reheating. Under the same reheating time, the grains of the semi-solid billet reheated by two-step reheating process are finer and rounder than those by isothermal reheating process. The present experimental results indicate that accelerating the formation of liquid phase during the two-step reheating process can restrain the coalescence of grains to a certain extent, and thus refine the grain size and promote the grain spheroidization.

  4. Effect of Gap Size on Coating Extrusion of Pb-GF Composite Wire by Theoretical Calculation and Experimental Investigation

    Institute of Scientific and Technical Information of China (English)

    Wenbin FANG; Hongfei SUN; Erde WANG; Yaohong GENG

    2005-01-01

    A new method using lead coated glass fiber to produce continuous wire for battery grid of electric vehicles (EVs)and hybrid electric vehicles (HEVs) was introduced. Under equal flow, both the maximum and minimum theoretical value of gap size were studied and estimation equation was established. The experimental results show that the gap size is a key parameter for the continuous coating extrusion process. Its maximum value (Hmax) is 0.24 mm and the minimum one (Hmin) is 0.12 mm. At a gap size of 0.18 mm, the maximum of metal extrusion per unit of time and optimal coating speed could be obtained.

  5. Experimental investigation and numerical simulation of large-sized aluminum tube extrusion forming

    Institute of Scientific and Technical Information of China (English)

    吕亚臣; 骆俊廷; 马春荣; 徐岩

    2008-01-01

    Large-sized aluminum tube has big section effect, aspect ratio and thin thickness, so that the extrusion technology is complex and the large specific pressure is generated in extrusion cavity. The temperature variation and velocity effect is difficult to control. The extrusion forming of large-sized aluminum tube was researched and simulated. Three-dimensional thermo-mechanical coupled finite element model was constructed and appropriate boundary conditions were given out. The results show that large-sized aluminum tube can be formed by isothermal extrusion through controlling the extrusion velocity and founding the relationship between extrusion velocity and extrusion temperature.

  6. Study of an industrial process for the synthesis of high molar mass ethylene oxide-propylene oxide copolymers usable as extrusible electrolyte; Etude d`un procede industriel de synthese de copolymeres oxyde d`ethylene-oxyde de propylene de hautes masses molaires utilisables comme electrolyte extrudable

    Energy Technology Data Exchange (ETDEWEB)

    Gramain, Ph. [Ecole Nationale Superieure de Chimie de Montpellier, 34 (France); Caselles, E. [Centre National de la Recherche Scientifique (CNRS), 67 - Strasbourg (France)

    1996-12-31

    The aim of this work is to develop an industrial process for the synthesis of an extrusible electrolyte polymer for lithium batteries. From literature data and precise specifications the high molar mass EO/OP copolymers synthesis by coordinative catalysis has been studied in order to reach a high productivity and to minimize the treatment steps. Two catalytic systems have been studied: the aluminium alkoxide-based Vandenberg-type catalysis and the calcium alcoholate amides catalysis. The first catalysis performed in solution gives excellent results. Its adaptation to silicon supported catalysis leads to a directly usable polymer in suspension but the productivity falls down and remains to be optimized. The calcium amide catalysis in heptane suspension generates acceptable productivities but also a too high proportion of low molar masses. Various approaches have been studied to minimize this proportion due to the presence of secondary sites that generate a cationic mechanism. The two synthesis ways explored are promising but remain to be optimized in order to increase the productivity of the efficient catalytic site and to reduce the formation of low molar masses generated by parasite catalytic sites. (J.S.) 9 refs.

  7. MICROSTRUCTURE OF Mg-6.4Zn-1.1Y ALLOY FABRICATED BY RAPID SOLIDIFICATION AND RECIPROCATING EXTRUSION

    Institute of Scientific and Technical Information of China (English)

    Z.M. Zhang; C.J. Xu; X.F. Guo

    2008-01-01

    In order to explore the methods to prepare high-strength quasicrystal-reinforced magnesium alloys, the flakes of rapidly solidified Mg-6.4Zn-1.1 Y magnesium alloy with a thickness of 50-60 um were obtained by a melt spinning single-roller device, and the flakes were then processed into rods by reciprocating extrusion and direct extrusion. The microstructure of the alloy was analyzed by optical microscope and SEM, and the constituent phases were identified by XRD. Phase transformation and its onset temperature were determined by differential thermal analyzer (DTA). The analysis result shows that rapid solidification for Mg-6.4Zn-1.1Y alloy can inhibit the eutectic reactions, broaden the solid solubility of Zn in a-Mg solute solution, and impede the formation of Mg3 Y2 Zn3 and MgZn2 compounds, and thus help the icosahedral Mg3 YZn6 quasicrystal formed directly from the melt. The mierostrueture of the flakes consists of the a-Mg solid solution and icosahedral Mg3 YZn6 quasierystal. Dense rods can be made from the flakes by two-pass reciprocating extrusion and direct extrusion. The interfaces between flakes in the rods can be welded and jointed perfectly. During the reciprocating extrusion and direct extrusion process, more Mg3 YZn6 compounds are precipitated and distributed uniformly, whereas the rods possess fine microstructures inherited from rapidly solidified flakes. The rods contain only two phases: amagnesium solid solution as matrix and fine icosahedral Mg3 YZn6 quasicrystal which disperses uniformly in the matrix.

  8. CRADA No. NFE-10-02715 Assessment of AFA Stainless Steels for Tube Products in Chemical Processing and Energy Production Applications

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Michael P [ORNL; Yamamoto, Yukinori [ORNL; Epler, Mario [Carpenter Technology Corporation; Magee, John H [Carpenter Technology Corporation

    2011-09-01

    Oak Ridge National Laboratory (ORNL) and Carpenter Technology Corporation (Carpenter) participated in an in-kind cost share cooperative research and development agreement (CRADA) effort under the auspices of the Energy Efficiency and Renewable Energy (EERE) Technology Maturation Program to assess material properties of several potential AFA family grades and explore the feasibility of producing alumina-forming austenitic (AFA) stainless steels in tubular form needed for many power generation and chemical process applications. Carpenter's Research Laboratory successfully vacuum melted 30 lb heats of seven candidate AFA alloy compositions representing a wide range of alloy content and intended application temperatures. These compositions were evaluated by ORNL and Carpenter R&D for microstructure, tensile properties, creep properties, and oxidation resistance. In parallel, additional work was directed toward an initial tube manufacture demonstration of a baseline AFA alloy. Carpenter successfully manufactured a 10,000 lb production heat and delivered appropriate billets to a partner for extrusion evaluation. Tube product was successfully manufactured from the baseline AFA alloy, indicating good potential for commercially produced AFA tubular form material.

  9. Modelling of semi-liquid aluminium flow in extrusion

    Directory of Open Access Journals (Sweden)

    G. Skorulski

    2007-04-01

    Full Text Available characterizing by low cost. The significant results may be quickly applying using theory of probability. The way of modelling the deformation mechanisms during extrusion of aluminium alloys in semi - liquid phase, the way of preparing samples and experimental technique has been analysed in the following work. On the ground of received results (i.e. registrations of consecutive process steps the grid of the flow velocity vectors on a flat sample surface was done. It allowed to draw conclusions which one of the basic deformation mechanisms is dominant in particular stage of the process. The technique of measurement has been shown as well. Experiments are made using plasticine and rape oil as a substiute materials. Some kind of different variants have been investigated. To ensure that such model experiments provide useful information it is essential to select model materials and prepare samples that would exhibit (preferably at room temperature similar behaviour and similar deformation mechanisms as those present during the actual deformation process of aluminium alloys in a semi-liquid state. In particular the FLS, SS and PDS mechanisms should be adequately reproduced.

  10. CHARACTERIZATION OF NEW TOOL STEEL FOR ALUMINUM EXTRUSION DIES

    Directory of Open Access Journals (Sweden)

    José Britti Bacalhau

    2014-06-01

    Full Text Available Aluminum extrusion dies are an important segment of application on industrial tools steels, which are manufactured in steels based on AISI H13 steel. The main properties of steels applied to extrusion dies are: wear resistance, impact resistance and tempering resistance. The present work discusses the characteristics of a newly developed hot work steel to be used on aluminum extrusion dies. The effects of Cr and Mo contents with respect to tempering resistance and the Al addition on the nitriding response have been evaluated. From forged steel bars, Charpy impact test and characterization via EPMA have been conducted. The proposed contents of Cr, Mo, and Al have attributed to the new VEX grade a much better tempering resistance than H13, as well as a deeper and harder nitrided layer. Due to the unique characteristics, this new steel provides an interesting alternative to the aluminum extrusion companies to increase their competitiveness.

  11. Effects of pelleting, extrusion, or extrusion and pelleting on energy and nutrient digestibility in diets containing different levels of fiber and fed to growing pigs.

    Science.gov (United States)

    Rojas, O J; Vinyeta, E; Stein, H H

    2016-05-01

    An experiment was conducted to determine effects of pelleting, extrusion, and extrusion and pelleting on energy and nutrient digestibility in diets containing low, medium, or high concentrations of fiber. Three diets were formulated: 1) the low-fiber diet contained corn and soybean meal; 2) the medium-fiber diet contained corn, soybean meal, and 25% distillers dried grains with solubles (DDGS); and 3) the high-fiber diet contained corn, soybean meal, 25% DDGS, and 20% soybean hulls. Each diet was divided into 4 batches after mixing. One batch was not further processed and was fed in a meal form, one batch was pelleted at 85°C, one batch was extruded at 115°C using a single-screw extruder, and one batch was extruded at 115°C and then pelleted at 85°C. Thus, 12 different diets were produced. Twenty-four growing pigs (26.5 ± 1.5 kg initial BW) had a T-cannula installed in the distal ileum and were allotted to the 12 diets in a split-plot design with 8 pigs allotted to the low-fiber diets, the medium-fiber diets, and the high-fiber diets, respectively. Diets were fed to the pigs during four 14-d periods. Within each type of diet, the 8 pigs were fed the diets produced using the 4 processing technologies. Therefore, there were 8 replicate pigs per diet. Pigs were adjusted to their diets for 14 d before the experiment was initiated. Each of the four 14-d periods consisted of 5 d for adaptation, 5 d of fecal collection according to the marker to marker approach, and ileal digesta were collected on d 13 and 14. Results indicated that pelleting, extrusion, or extrusion and pelleting improved ( < 0.05) the apparent ileal digestibility of starch and most indispensable AA. In most cases, there were no differences between the pelleted, the extruded, and the extruded and pelleted diets. The apparent total tract digestibility of GE was also improved ( < 0.05) by pelleting and by the combination of extrusion and pelleting. The ME of pelleted diets was greater ( < 0.05) than

  12. Semi-solid squeeze casting process of a ZL109 alloy

    Institute of Scientific and Technical Information of China (English)

    ZHAI Yanbo; LIU Changming; HAN Zhaotang; WANG Kai

    2008-01-01

    The structure evolution of the ZL109 alloy in the process of semi-solid squeeze casting and the mechanical properties of the components were investigated. The results show that (1) the eutectic silicon phase in original billets is refined in the low super-heat casting process; (2) the eutectic structure in billets starts to fuse and the crystals of the eutectic silicon phase are refined further and sphericized in the remelting process of billets; (3) in the semi-solid ,squeeze casting process, the sphericity of the α phase and the refining of the silicon phase occur, owing to the friction between solid and liquid; (4) in the process of heat treatment, the eutectic α phase aggregates with the primary α phase and the eutectic silicon pieces aggregate together. The elongation of the semi-solid component after heat treatment rises to 1.42%.

  13. Similar extrusion and mapping optimization of die cavity modeling for special-shaped products

    Institute of Scientific and Technical Information of China (English)

    QI Hong-yuan; WANG Shuang-xin; ZHU Heng-jun

    2006-01-01

    Aimed at the modeling issues in design and quick processing of extruding die for special-shaped products, with the help of Conformal Mapping theory, Conformal Mapping function is determined by the given method of numerical trigonometric interpolation. Three-dimensional forming problems are transformed into two-dimensional problems, and mathematical model of die cavity surface is established based on different kinds of vertical curve, as well as the mathematical model of plastic flow in extruding deformation of special-shaped products gets completed. By upper bound method, both vertical curves of die cavity and its parameters are optimized. Combining the optimized model with the latest NC technology, NC Program of die cavity and its CAM can be realized. Taking the similar extrusion of square-shaped products with arc radius as instance, both metal plastic similar extrusion and die cavity optimization are carried out.

  14. Extrusion of blends of cassava leaves and cassava flour: physical characteristics of extrudates

    Directory of Open Access Journals (Sweden)

    Cristiane da Cunha Salata

    2014-09-01

    Full Text Available A cassava-based puffed snack was produced using a single screw extruder to determine the effect of the raw material composition (cassava leaf flour and moisture and the process parameters (extrusion temperature and screw speed on the physical characteristics of an extruded-expanded snack. A central composite rotational design, including four factors with 30 treatments, was used with the following as dependent variables: expansion index, specific volume, water solubility index, water absorption index, color (L*, a*, b*, and hardness. Under conditions of low moisture content (12 to 14%, low percentage of cassava leaf flour (2 to 4%, and intermediate conditions of extrusion temperature (100°C and screw speed (230rpm, it was possible to obtain puffed snack products with desirable characteristics.

  15. A Mathematical Model on the Resolution of Extrusion Bioprinting for the Development of New Bioinks

    Directory of Open Access Journals (Sweden)

    Ratima Suntornnond

    2016-09-01

    Full Text Available Pneumatic extrusion-based bioprinting is a recent and interesting technology that is very useful for biomedical applications. However, many process parameters in the bioprinter need to be fully understood in order to print at an adequate resolution. In this paper, a simple yet accurate mathematical model to predict the printed width of a continuous hydrogel line is proposed, in which the resolution is expressed as a function of nozzle size, pressure, and printing speed. A thermo-responsive hydrogel, pluronic F127, is used to validate the model predictions. This model could provide a platform for future correlation studies on pneumatic extrusion-based bioprinting as well as for developing new bioink formulations.

  16. Numerical Studies of Low Cycle Fatigue in Forward Extrusion Dies

    DEFF Research Database (Denmark)

    Pedersen, Thomas Ø

    2000-01-01

    Forward extrusion dies typically fail due to transverse fatigue cracks or wear. Fatigue cracks are initiated in regions where the material is subjected to repeated plastic deformations, e.g. the transition radius in a forward extrusion die, in the present work, a material model capable of describ...... be controlled by means of the pre-stressing system or the geometry of the die insert. (C) 2000 Elsevier Science B.V. All rights reserved....

  17. Making Ceramic/Polymer Parts By Extrusion Stereolithography

    Science.gov (United States)

    Stuffle, Kevin; Mulligan, A.; Creegan, P.; Boulton, J. M.; Lombardi, J. L.; Calvert, P. D.

    1996-01-01

    Extrusion stereolithography developmental method of computer-controlled manufacturing of objects out of ceramic/polymer composite materials. Computer-aided design/computer-aided manufacturing (CAD/CAM) software used to create image of desired part and translate image into motion commands for combination of mechanisms moving resin dispenser. Extrusion performed in coordination with motion of dispenser so buildup of extruded material takes on size and shape of desired part. Part thermally cured after deposition.

  18. Efeito de parâmetros de extrusão na cor E propriedades de pasta da farinha de mandioquinha-salsa (Arracacia xanthorrhiza Effect of extrusion parameters on color and pasting properties of peruvian carrot flour (Arracacia xanthorrhiza

    Directory of Open Access Journals (Sweden)

    Bruna Menegassi

    2007-12-01

    Full Text Available Processou-se neste trabalho a farinha de mandioquinha-salsa (Arracacia xanthorrhiza Bancr. em uma linha de extrusão (mono rosca variando as condições operacionais: umidade da farinha (11-19%, temperatura de extrusão (86-154ºC e taxa de rotação da rosca (136-272rpm. Os parâmetros de cor analisados foram luminosidade (L* e os componentes de cromaticidade a* e b*. Os parâmetros de propriedade de pasta analisados foram viscosidade inicial, pico de viscosidade, quebra de viscosidade, tendência a retrogradação e viscosidade final. Os resultados obtidos mostraram que a umidade da matéria-prima interferiu nos componentes de cor das farinhas com efeito significativo sobre a luminosidade e croma a*, e a temperatura interferiu no croma b* . Quanto ao efeito dos parâmetros de processo sobre as propriedades de pasta, a umidade interferiu nas viscosidades inicial e final dos produtos, pico e quebra de viscosidade, enquanto a temperatura de extrusão e a rotação da rosca tiveram influência sobre a tendência a retrogradação e viscosidade final dos produtos.In this work peruvian carrot flour (Arracacia xanthorrhiza Bancr. was processed in a single screw extruder at different moisture contents (11-19%, extrusion temperature (86-154ºC and screw speed (136-272rpm. The parameters L*, a* and b* of color were analyzed in extruded flours. The viscosity related parameters determined include initial viscosity, viscosity peak, breakdown, setback and final viscosity. The results showed effect of feed moisture on flour color (L* and a* and the extrusion temperature influenced b*. Moisture content of the feed had effect on initial and final viscosity, viscosity peak and breakdown. Extrusion temperature and screw speed had effect on final viscosity and setback.

  19. Inline monitoring and a PAT strategy for pharmaceutical hot melt extrusion.

    Science.gov (United States)

    Wahl, Patrick R; Treffer, Daniel; Mohr, Stefan; Roblegg, Eva; Koscher, Gerold; Khinast, Johannes G

    2013-10-15

    Implementation of continuous manufacturing in the pharmaceutical industry requires tight process control. This study focuses on a PAT strategy for hot melt extrusion of vegetable calcium stearate (CaSt) as matrix carrier and paracetamol as active pharmaceutical ingredient (API). The extrusion was monitored using in-line near-infrared (NIR) spectroscopy. A NIR probe was located in the section between the extrusion screws and the die, using a novel design of the die channel. A chemometric model was developed based on premixes at defined concentrations and was implemented in SIPAT for real time API concentration monitoring. Subsequently, step experiments were performed for different API concentrations, screw speeds and screw designs. The predicted API concentration was in good agreement with the pre-set concentrations. The transition from one API plateau to another was a smooth curve due to the mixing behaviour of the extruder. The accuracy of the model was confirmed via offline HPLC analysis. The screw design was determined as the main influential factor on content uniformity (CU). Additionally the influence of multiple feeders had a significant impact on CU. The results demonstrate that in-line NIR measurements is a powerful tool for process development (e.g., mixing characterization), monitoring and further control strategies. PMID:23911343

  20. Green route to modification of wood waste, cellulose and hemicellulose using reactive extrusion.

    Science.gov (United States)

    Vaidya, Alankar A; Gaugler, Marc; Smith, Dawn A

    2016-01-20

    A large volume of wood waste is produced in timber processing industry which traditionally used in low value applications. Here, value addition to the wood waste (Sander dust) and cellulose, hemicellulose isolated thereof by functionalisation using cyclic anhydrides in a solvent-free and green reactive extrusion process is reported. The effect of extrusion temperature, catalyst and different weight ratios of Sander dust (SD):succinic anhydride (SA) on the esterification reaction is evaluated. The esterified products were characterised by the acid value, degree of substitution (DS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), solid state (13)C NMR and thermo-gravimetric analysis (TGA). Under optimum extrusion conditions, mixed esters are formed, with highest acid value obtained for succinylation of cellulose (0.122 g/g at DS of 0.350) which is two times higher compared to succinylated SD (0.059 g/g at a weight gain of 0.452) and hemicellulose (0.043 g/g at DS of 0.290). The reactivity trend for individual anhydride was: (1) SA-Cellulose>SD>hemicellulose; (2) maleic anhydride (MA)-SD>hemicellulose>cellulose and (3) dodecenyl succinic anhydride (DDSA)-SD ≈ cellulose ≫ hemicellulose. The pendant free carboxyl groups generated through functionalisation of wood waste, cellulose and hemicellulose without the presence of polymeric carriers will allow more tailored or targeted modification of wood-plastic composites. PMID:26572467