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Sample records for cast aluminum alloy

  1. Casting Characteristics of Aluminum Die Casting Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Makhlouf M. Makhlouf; Diran Apelian

    2002-02-05

    The research program investigates the casting characteristics of selected aluminum die casting alloys. Specifically, the alloys' tendencies towards die soldering and sludge formation, and the alloys' fluidity and machinability are evaluated. It was found that: When the Fe and Mn contents of the alloy are low; caution has to be taken against possible die soldering. When the alloy has a high sludge factor, particularly a high level of Fe, measures must be taken to prevent the formation of large hardspots. For this kind of alloy, the Fe content should be kept at its lowest allowable level and the Mn content should be at its highest possible level. If there are problems in die filling, measures other than changing the alloy chemistry need to be considered first. In terms of alloy chemistry, the elements that form high temperature compounds must be kept at their lowest allowable levels. The alloys should not have machining problems when appropriate machining techniques and machining parameters are used.

  2. Microstructures and properties of aluminum die casting alloys

    Energy Technology Data Exchange (ETDEWEB)

    M. M. Makhlouf; D. Apelian; L. Wang

    1998-10-01

    This document provides descriptions of the microstructure of different aluminum die casting alloys and to relate the various microstructures to the alloy chemistry. It relates the microstructures of the alloys to their main engineering properties such as ultimate tensile strength, yield strength, elongation, fatigue life, impact resistance, wear resistance, hardness, thermal conductivity and electrical conductivity. Finally, it serves as a reference source for aluminum die casting alloys.

  3. China’s Aluminum Alloy Die Castings Industry has Promising Prospects

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>Engine aluminum alloy engine block die casting experienced rapid development in recent years. Domestic enterprises introduced large die casting machine automatic production lines, and developed large aluminum alloy die cast-

  4. The Role of Particles in Fatigue Crack Propagation of Aluminum Matrix Composites and Casting Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    Zhenzhong CHEN; Ping HE; Liqing CHEN

    2007-01-01

    Fatigue crack propagation (FCP) behaviors were studied to understand the role of SiC particles in 10 wt pct SiCp/A2024 composites and Si particles in casting aluminum alloy A356. The results show that a few particles appeared on the fracture surfaces in SiCp/Al composites even at high AK region, which indicates that cracks propagated predominantly within the matrix avoiding SiC particles due to the high strength of the particles and the strong particle/matrix interface. In casting aluminum alloy, Si particle debonding was more prominent.Compared with SiCp/Al composite, the casting aluminum alloy exhibited lower FCP rates, but had a slight steeper slope in the Paris region. Crack deflection and branching were found to be more remarkable in the casting aluminum alloy than that in the SiCp/Al composites, which may be contributed to higher FCP resistance in casting aluminum alloy.

  5. Die Casting Mold Design for Aluminum Alloy Shell of Instrument

    Directory of Open Access Journals (Sweden)

    Li Yuanyuan

    2015-01-01

    Full Text Available This paper is about die casting mold design for aluminum alloy shell of instrument. Three-dimensional model of the casting and mold are designed by using Pro/Engineer and AutoCad which can analyze forming quality. Digital design and theoretical calculation can greatly shorten product development cycle and mold design cycle, improve the accuracy of product design and mold design, and reduce the cost of mold design.

  6. High speed twin roll caste for aluminum alloy thin strip

    Directory of Open Access Journals (Sweden)

    T. Haga

    2007-09-01

    Full Text Available Purpose: In the present study, effectiveness of a high-speed twin roll caster for recycling aluminum alloy was investigated.Design/methodology/approach: The effects of the high-speed twin roll caster on alleviating the deterioration of mechanical properties by impurities were investigated. Properties of the cast strip were investigated by metalography, a tension test, and a bending test.Findings: A vertical type twin roll caster for strip casting of aluminum alloys was devised. The strip, which was thinner than 3 mm, could be cast at speeds higher than 60 m/min. Features of the twin roll casters are as below. Copper rolls were used and lubricant was not used in order to increase the casting speed. A casting nozzle was used to set the solidification length precisely. Heat transfer between melt and the roll was improved by hydrostatic pressure of the melt. Separating force was very small in order to prevent sticking of the strip to the roll. Low superheat casting was carried out in order to improve microstructure of the strip. In the present study, effectiveness of a high-speed and high-cooling rate twin roll caster of the present study for recycling aluminum alloy was investigated. Fe was added as impurity to 6063 and A356. The roll caster of the present study was useful to decrease the influence of impurity of Fe.Research limitations/implications: A high-speed twin roll caster of vertical type was designed and assembled to cast aluminum alloy thin strip.Originality/value: The results demonstrate that the high-speed twin roll caster can improve the deterioration by impurities.

  7. Casting defects in low-pressure die-cast aluminum alloy wheels

    Science.gov (United States)

    Zhang, B.; Cockcroft, S. L.; Maijer, D. M.; Zhu, J. D.; Phillion, A. B.

    2005-11-01

    Defects in automotive aluminum alloy casting continue to challenge metallurgists and production engineers as greater emphasis is placed on product quality and production cost. A range of casting-related defects found in low-pressure die-cast aluminum wheels were examined metallographically in samples taken from several industrial wheel-casting facilities. The defects examined include macro- and micro- porosity, entrained oxide films, and exogenous oxide inclusions. Particular emphasis is placed on the impact of these defects with respect to the three main casting-related criteria by which automotive wheel quality are judged: wheel cosmetics, air-tightness, and wheel mechanical performance.

  8. Texture evolution of continuous cast and direct chill cast AA 3003 aluminum alloys during cold rolling

    International Nuclear Information System (INIS)

    The texture evolution of continuous cast (CC) and direct chill cast (DC) AA 3003 aluminum alloys during cold rolling was investigated by X-ray diffraction. The relationship between texture volume fractions and rolling true strain was described quantitatively by mathematical formulae. The effect of processing method (CC vs. DC) on texture evolution was determined

  9. Optimization of Squeeze Casting for Aluminum Alloy Parts

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Qingming Chang; Yulong Zhu

    2002-07-30

    This study was initiated with the installation of a new production size UBE 350 Ton VSC Squeeze Casting system in the Metal Casting Laboratory at Case Western University. A Lindberg 75k W electrical melting furnace was installed alongside. The challenge of installation and operation of such industrial-size equipment in an academic environment was met successfully. Subsequently, a Sterling oil die heater and a Visi-Track shot monitoring system were added. A significant number of inserts were designed and fabricated over the span of the project, primarily for squeeze casting different configurations of test bars and plates. A spiral ''ribbon insert'' for evaluation of molten metal fluidity was also fabricated. These inserts were used to generate a broad range of processing conditions and determine their effect on the quality of the squeeze cast parts. This investigation has studied the influence of the various casting variables on the quality of indirect squeeze castings primarily of aluminum alloys. The variables studied include gating design, fill time and fill patter, metal pressure and die temperature variations. The quality of the die casting was assessed by an analysis of both their surface condition and internal soundness. The primary metal tested was an aluminum 356 alloy. In addition to determining the effect of these casting variables on casting quality as measured by a flat plate die of various thickness, a number of test bar inserts with different gating designs have been inserted in the squeeze casting machine. The mechanical properties of these test bars produced under different squeeze casting conditions were measured and reported. The investigation of the resulting properties also included an analysis of the microstructure of the squeeze castings and the effect of the various structural constituents on the resulting properties. The main conclusions from this investigation are as follows: The ingate size and shape are very important

  10. TESTING OF ALUMINUM-SILICON ALLOYS MECHANICAL PROPERTIES ON SEPARATELY CASTED SPECIMENS

    OpenAIRE

    Krushenko, G.

    2010-01-01

    The mechanical properties of aluminum alloys before casting into moulds were determined on separately casted control specimens casted in horizontal or vertical forms. A comparison of the mechanical properties (tensile strength t, elongation 8, hardness HB) of 12-mm-diameter individually casted of AK7ch alloy control specimens and its density in the solid state (p) showed that it is necessary to use specimens casted in a horizontal mold for evaluation of castings quality. It was estimated that...

  11. Microstructure and properties of vacuum counter-pressure cast aluminum alloy

    Directory of Open Access Journals (Sweden)

    YAN Qing-song

    2006-05-01

    Full Text Available The microstructure and properties of vacuum counter-pressure cast aluminum alloy were studied. Results indicated that under the condition of vacuum counter-pressure, liquid melts fill mould cavity under the vacuum and crystallize under high pressure which have very good effect on nucleation and solidification feeding. Compared with gravity casting, the microstructure of vacuum counter-pressure cast aluminum alloy is much finer and more uniformly distributed. Mechanical properties of vacuum counter-pressure cast aluminum alloy are improved significantly.

  12. Microstructure and properties of vacuum counter-pressure cast aluminum alloy

    OpenAIRE

    YAN Qing-song; Yu, Huan; WEI Bo-kang

    2006-01-01

    The microstructure and properties of vacuum counter-pressure cast aluminum alloy were studied. Results indicated that under the condition of vacuum counter-pressure, liquid melts fill mould cavity under the vacuum and crystallize under high pressure which have very good effect on nucleation and solidification feeding. Compared with gravity casting, the microstructure of vacuum counter-pressure cast aluminum alloy is much finer and more uniformly distributed. Mechanical properties of vacuum co...

  13. Rheological behavior of continuous roll casting process of aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    ZHAN Li-hua; ZHONG Jue; LI Xiao-qian; HUANG Ming-hui

    2005-01-01

    The rheological behavior of aluminum alloy and its influencing factors in physical simulation of continuous roll casting process were studied by using a Gleeble-1500 thermal-mechanical simulation tester with a set of special clamp system. The relationships between the flow stress and the strain rate in the deformation process of simulating roll casting experiment were obtained. The results show that four different characteristic stages exist in the temperature range of the whole rheological process. The first occurs when the temperature is higher than 600℃, which belongs to the creep deformation stage; the second occurs when the temperature lies in the range of 500-600℃, and it can be regarded as the high temperature and low stress level deformation stage; the third occurs when the temperature decreases to the range of 300-500℃, it is considered to be the middle stress level deformation stage; the last occurs when the temperature is less than 300℃ and the strain rate is less than 1.00 s -1, it belongs to middle stress level deformation stage. But when the strain rate is larger than 1.00 s -1, it belongs to the high stress level deformation stage. And the relative constitutive models suitable for the four different stages of continuous roll casting process were established through multivariate linear regression analysis of the experimental data.

  14. Centrifugal Casting Features/Metallurgical Characterization of Aluminum Alloys

    International Nuclear Information System (INIS)

    This paper deals with the study of centrifugal effects on aluminium castings under high G values. Most of the studies in this domain (FGMs obtained by centrifugal casting) deal with functionally graded composites reinforced with a solid phase such as silicon particles or others. However, in this study it will be shown that unreinforced aluminium alloys may be significantly influenced by the centrifugal effect and that functionally graded castings are also obtained. It has been observed that the centrifugal effect may increase in some alloys, depending on the relative position in the castings, the rupture strength by approx. 50%, and rupture strain by about 300%, as compared to the gravity casting technique. The Young's modulus may also increase by about 20%. It has also been reported that in vertical centrifugal castings there are mainly three aspects that affect the components thus obtained, namely: fluid dynamics; vibration (inherent to the system); and centrifugal force. These features have a different effect on the castings depending on the aluminium alloy. In this paper, an analysis of the most important effects of the centrifugal casting process on metallurgical features is conducted. A solidification characterization at several points along the mould will be made in order to have an accurate idea of both the fluid dynamics inside the mould during the casting and the solidification behavior in different parts of the component. These two analyses will be related to the metallurgical properties (phase distribution; SDAS; eutectic silicon content and shape, pores density and shape) along the component and mainly along the direction of the centrifugal pressure. A comparison between castings obtained by both centrifugal casting technique and gravity casting technique is made for reference (gravity casting)

  15. Centrifugal Casting Features/Metallurgical Characterization of Aluminum Alloys

    Science.gov (United States)

    Chirita, G.; Stefanescu, I.; Soares, D.; Cruz, D.; Silva, F. S.

    2008-02-01

    This paper deals with the study of centrifugal effects on aluminium castings under high G values. Most of the studies in this domain (FGMs obtained by centrifugal casting) deal with functionally graded composites reinforced with a solid phase such as silicon particles or others. However, in this study it will be shown that unreinforced aluminium alloys may be significantly influenced by the centrifugal effect and that functionally graded castings are also obtained. It has been observed that the centrifugal effect may increase in some alloys, depending on the relative position in the castings, the rupture strength by approx. 50%, and rupture strain by about 300%, as compared to the gravity casting technique. The Young's modulus may also increase by about 20%. It has also been reported that in vertical centrifugal castings there are mainly three aspects that affect the components thus obtained, namely: fluid dynamics; vibration (inherent to the system); and centrifugal force. These features have a different effect on the castings depending on the aluminium alloy. In this paper, an analysis of the most important effects of the centrifugal casting process on metallurgical features is conducted. A solidification characterization at several points along the mould will be made in order to have an accurate idea of both the fluid dynamics inside the mould during the casting and the solidification behavior in different parts of the component. These two analyses will be related to the metallurgical properties (phase distribution; SDAS; eutectic silicon content and shape, pores density and shape) along the component and mainly along the direction of the centrifugal pressure. A comparison between castings obtained by both centrifugal casting technique and gravity casting technique is made for reference (gravity casting).

  16. Aluminum Alloy Semisolid Strip Casting Using an Unequal Diameter Twin Roll Caster

    OpenAIRE

    Haga, T.; Sakaguchi, H; H. Inui; H. Watari; S. Kumai

    2005-01-01

    Purpose: A Purpose of the present study was to break through the disadvantage of the twin roll caster for aluminum alloy. They were slow casting speed and limitation of alloy. For example, the casting speed was slower than 5 m/min, and casting of hypereutectic Al-Si alloy was difficult. In order to break through the disadvantages, semisolid casting using an unequal diameter twin roll caster was tested its ability.Design/methodology/approach: The specification of the unequal diameter twin roll...

  17. Technical parameters in electromagnetic continuous casting of aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    李玉梅; 张兴国; 贾非; 姚山; 金俊泽

    2003-01-01

    The temperature field of aluminum ingot during electromagnetic continuous casting was calculated by the numerical method, and the effects of cooling water strength, position of the cooling water holes and pouring temperature as well as induction heat on casting speed, were studied. The results show that among the technical parameters the distance from the position of the cooling water holes to the bottom of the mold is the most important factor, whose change from 20mm to 15mm and from 15mm to 10mm causes the setting rate increasing respectively by 0.14mm/s and 0.3mm/s.The calculated results also agree with the experiment well. The simulation program can be used to determine technical parameters of electromagnetic casting of aluminum ingot effectively.

  18. Influences on Burr Size During Face-Milling of Aluminum Alloys and Cast Iron

    OpenAIRE

    Shefelbine, Wendy; Dornfeld, David

    2004-01-01

    The Exit Order Sequence (EOS) theory discussed by previous LMA students predicts the size of burrs formed during face milling. Other influences are tool geometry, coolant use, and material properties in aluminum silicon alloys and cast iron. Used, worn tools also increase the size of the burr. The effect of speed and feed are also discussed, particularly with regards to cast iron.

  19. Effect of Electromagnetic Frequency on Microstructures of Continuous Casting Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The relationship between electromagnetic frequency and microstructures of continuous casting aluminum alloyswas studied. 7075 aluminum alloy ingot of 100 mm in diameter was produced by electromagnetic continuouscasting process, the microstructures of as-cast ingot was examined by scanning electron microscopy (SEM) equippedwith energy dispersive spectrometer (EDS). The results showed that electromagnetic frequency greatly influencedsegregation and microstructures of as-cast ingot, and product quality can be guaranteed by the application of aproper frequency. Electromagnetic frequency plays a significant role in solute redistribution; Iow frequency is moreefficient for promoting solution of alloying elements.

  20. Strengthening technology and mechanism for semi-solid die casting of aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    张恒华; 许珞萍; 邵光杰; 余忠土

    2003-01-01

    Combined with theoretical evaluation,an optimized strengthening process for the semi-solid die castings of A356 aluminum alloy was obtained by studying the mechanical properties of castings solution treated and aged under different conditions in detail,then,the semi-solid die castings and liquid die castings were heat treated with the optimized process.The results show that the mechanical properties of semi-solid die castings of aluminum alloy are superior to those of the liquid die castings,especially the strengthening degree of heat treated semi-solid die castings is much greater than that of liquid die castings with the tensile strength more than 330 Mpa and the elongation more than 10%,and this is mainly contributed to the non-dendritic and more compact microstructure of semi-solid die castings.The strengthening mechanism of heat treatment for the semi-solid die castings of A356 aluminum alloy is due to the dispersive precipitation of the second phase(Mg2 Si)and formation of GP Zone.

  1. Rapid precision casting for complex thin-walled aluminum alloy parts

    OpenAIRE

    Xuanpu DONG; Naiyu HUANG; Zitian FAN

    2004-01-01

    Based on Vacuum Differential Pressure Casting (VDPC) precision forming technology and the Selective Laser Sintering (SLS) Rapid Prototyping (RP) technology, a rapid manufacturing method called Rapid Precision Casting (RPC) process from computer three-dimensional solid models to metallic parts was investigated. The experimental results showed that the main advantage of RPC was not only its ability to cast higher internal quality and more accurate complex thin-walled aluminum alloy parts, but a...

  2. As-cast structure of DC casting 7075 aluminum alloy obtained under dual-frequency electromagnetic field

    Institute of Scientific and Technical Information of China (English)

    Zhi-hao Zhao; Zhen Xu; Gao-song Wang; Qing-feng Zhu; Jian-zhong Cui

    2014-01-01

    We have experimentally determined the as-cast structures of semi-continuous casting 7075 aluminum alloy obtained in the pres-ence of dual-frequency electromagnetic field. Results suggest that the use of dual-frequency electromagnetic field during the semi-continuous casting process of 7075 aluminum alloy ingots reduces the thickness of the surface segregation layer, increases the height of the melt menis-cus, enhances the surface quality of the ingot, and changes the surface morphology of the melt pool. Moreover, low-frequency electromag-netic field was found to show the most obvious influence on improving the as-cast structure because of its high permeability in conductors.

  3. Adhesion enhancement of titanium nitride coating on aluminum casting alloy by intrinsic microstructures

    Science.gov (United States)

    Nguyen, Chuong L.; Preston, Andrew; Tran, Anh T. T.; Dickinson, Michelle; Metson, James B.

    2016-07-01

    Aluminum casting alloys have excellent castability, high strength and good corrosion resistance. However, the presence of silicon in these alloys prevents surface finishing with conventional methods such as anodizing. Hard coating with titanium nitride can provide wear and corrosion resistances, as well as the aesthetic finish. A critical factor for a durable hard coating is its bonding with the underlying substrate. In this study, a titanium nitride layer was coated on LM25 casting alloy and a reference high purity aluminum substrate using Ion Assisted Deposition. Characterization of the coating and the critical interface was carried out by a range of complementing techniques, including SIMS, XPS, TEM, SEM/EDS and nano-indentation. It was observed that the coating on the aluminum alloy is stronger compared to that on the pure aluminum counterpart. Silicon particles in the alloy offers the reinforcement though mechanical interlocking at microscopic level, even with nano-scale height difference. This reinforcement overcomes the adverse effect caused by surface segregation of magnesium in aluminum casting alloys.

  4. Cold cracking in DC-cast high strength aluminum alloy ingots: An intrinsic problem intensified by casting process parameters

    NARCIS (Netherlands)

    Lalpoor, M.; Eskin, D.G.; Ruvalcaba, D.; Fjaer, H.G.; Ten Cate, A.; Ontijt, N.; Katgerman, L.

    2011-01-01

    For almost half a century the catastrophic failure of direct chill (DC) cast high strength aluminum alloys has been challenging the production of sound ingots. To overcome this problem, a criterion is required that can assist the researchers in predicting the critical conditions which facilitate the

  5. Development of Deformation-Semisolid-Casting (D-SSC) Process and Applications to Some Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recent advances in the semisolid casting technologies are introduced for aluminum alloys. The advantages of the rheocast and thixocast methods to fabricate alloys with refined spheroidized α-Al particles are described.The deformation-semisolid-casting (D-SSC) process developed by the author's group is presented. The D-SSC process is extremely effective to produce microstructures of refined intermetallic compound particles as well as the spheroidized α-Al particles in the Al-Si based alloys containing highly concentrated Fe. In the D-SSC processed Al-Si-Cu alloy high elongation of about 20% was achieved even contained concentrated impurity of Fe. The D-SSC process is also useful to produce wrought aluminum alloys with microstructures of refined α-Al particles.

  6. Recrystallization microstructures and textures in AA 5052 continuous cast and direct chill cast aluminum alloy

    International Nuclear Information System (INIS)

    Commercially produced hot bands of AA 5052 continuous cast (CC) and direct chill (DC) cast aluminum alloys were cold rolled to (thickness) reductions of 70%, 80%, and 90% followed by annealing at different conditions. The recrystallization kinetics are found equivalent for both the CC and DC materials. Recrystallization microstructures are different between the CC and DC materials. Evolution of recrystallization texture in the CC and DC materials were investigated by using three-dimensional orientation distribution functions (ODFs) that were determined by X-ray diffraction. The recrystallization texture was correlated with cold rolling reduction (prior to annealing), annealing temperature, and annealing time. Results showed that the R {124} and cube {001} are dominant recrystallization texture components in both CC and DC materials. During annealing, the intensity and volume fraction of the cube component strongly depend on the prior cold rolling history. In contrast, the intensity and volume fraction of the R component remains almost constant regardless of the different cold rolling reductions prior to annealing. After complete recrystallization, the intensity and volume fraction of both R and cube components appear to be independent of the annealing temperature and annealing time

  7. Process Modeling of Low-Pressure Die Casting of Aluminum Alloy Automotive Wheels

    Science.gov (United States)

    Reilly, C.; Duan, J.; Yao, L.; Maijer, D. M.; Cockcroft, S. L.

    2013-09-01

    Although on initial inspection, the aluminum alloy automotive wheel seems to be a relatively simple component to cast based on its shape, further insight reveals that this is not the case. Automotive wheels are in a select group of cast components that have strict specifications for both mechanical and aesthetic characteristics due to their important structural requirements and their visibility on a vehicle. The modern aluminum alloy automotive wheel continues to experience tightened tolerances relating to defects to improve mechanical performance and/or the physical appearance. Automotive aluminum alloy wheels are assessed against three main criteria: wheel cosmetics, mechanical performance, and air tightness. Failure to achieve the required standards in any one of these categories will lead to the wheel either requiring costly repair or being rejected and remelted. Manufacturers are becoming more reliant on computational process modeling as a design tool for the wheel casting process. This article discusses and details examples of the use of computational process modeling as a predictive tool to optimize the casting process from the standpoint of defect minimization with the emphasis on those defects that lead to failure of aluminum automotive wheels, namely, macroporosity, microporosity, and oxide films. The current state of applied computational process modeling and its limitations with regard to wheel casting are discussed.

  8. THE INVESTIGATION ON THE RHEOLOGICAL BEHAVIOR OF SEMI-SOLID ALUMINUM ALLOY DURING DIE CASTING

    Institute of Scientific and Technical Information of China (English)

    X.J. Yang; J. Lin

    2002-01-01

    Under the condition of die casting and reheating temperature of 570-580° C, the Rhe-ological behavior of semi-solid aluminum alloy (A356) is pseudoplasticity at the shearrate of 2×10s-1×104 s-1, and also shows dilatancy at the rate over 106s-1.

  9. Comparison of recrystallization texture in cold-rolled continuous cast AA5083 and 5182 aluminum alloys

    International Nuclear Information System (INIS)

    The recrystallization microstructure and texture of cold-rolled continuous cast AA 5083 and 5182 aluminum alloys with and without prior heat treatment were investigated by optical microscopy, X-ray diffraction and TEM. The results obtained were discussed with regard to the effect of Zener-particle pinning

  10. Comparison of recrystallization texture in cold-rolled continuous cast AA5083 and 5182 aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Li, J. [Department of Civil and Environmental Engineering, Beijing Jiaotong University (China); Liu, W.C. [Department of Chemical and Materials Engineering, University of Kentucky, 177 Anderson Hall, Lexington, KY 40506 (United States); Zhai, T. [Department of Chemical and Materials Engineering, University of Kentucky, 177 Anderson Hall, Lexington, KY 40506 (United States)]. E-mail: tzhai@engr.uky.edu; Kenik, E.A. [Metals and Ceramics Division, Oak Ridge National Laboratory, 100 Bethel Valley Road, Building 4515, MS-6064, P.O. Box 2008, Oak Ridge, TN 37831-6064 (United States)

    2005-02-15

    The recrystallization microstructure and texture of cold-rolled continuous cast AA 5083 and 5182 aluminum alloys with and without prior heat treatment were investigated by optical microscopy, X-ray diffraction and TEM. The results obtained were discussed with regard to the effect of Zener-particle pinning.

  11. Modeling mechanical properties of cast aluminum alloy using artificial neural network

    International Nuclear Information System (INIS)

    Modeling is widely used to investigate the mechanical properties of engineering materials due to increasing demand of low cost and high strength to weight ratio for many engineering applications. The aluminum casting alloys are cost competitive material and possess the desired properties. The mechanical properties largely depend upon composition of alloys and their processing method. Alloy design involves controlling mechanical properties via optimization of the composition and processing parameters. For optimization the possible root is empirical modeling and its more refined version is the analysis of the wide range of data using ANN (Artificial Neural Networks) modeling. The modeling of mechanical properties of the aluminum alloys are the main objective of present work. For this purpose, some data were collected and experimentally prepared using conventional casting method. A MLP (Multilayer Perceptron) network was developed, which is trained by using the error back propagation algorithm. (author)

  12. Aluminum Alloy Semisolid Strip Casting Using an Unequal Diameter Twin Roll Caster

    Directory of Open Access Journals (Sweden)

    T. Haga

    2005-12-01

    Full Text Available Purpose: A Purpose of the present study was to break through the disadvantage of the twin roll caster for aluminum alloy. They were slow casting speed and limitation of alloy. For example, the casting speed was slower than 5 m/min, and casting of hypereutectic Al-Si alloy was difficult. In order to break through the disadvantages, semisolid casting using an unequal diameter twin roll caster was tested its ability.Design/methodology/approach: The specification of the unequal diameter twin roll caster is as below. The diameter of the upper roll was 250 mm, and that of the lower roll was 1000 mm. The width of the roll was 100 mm. The semisolid slurry was made by a cooling slope.Findings: The microstructure of the strip became very fine. Especially, primary and eutectic Si became very fine. This was the effect of rapid solidification. As the result, the ductility of Al-16%Si was improved.Research limitations/implications: 6111 aluminum alloy strip was cast at speeds of 5, 10 and 20 m/min. This caster could cast the strip at the speeds higher than the conventional twin roll caster. Start of casting was very easy. The hypereutectic Al-16%Si alloy, which has wide freezing zone, could be cast in to the strip by the unequal diameter twin roll caster. This was the effect of the cooling of the strip on the lower roll.Originality/value: The roll cast Al-16mass%Si strip had good ductility, and could be cold rolled. Annealed 0.5 mm thick Al-16mass%Si could be bent at radius of 0.75mm.

  13. Processing map of as-cast 7075 aluminum alloy for hot working

    Institute of Scientific and Technical Information of China (English)

    Guo Lianggang a; Yang Shuang a; Yang He a; Zhang Jun b

    2015-01-01

    The true stress–strain curves of as-cast 7075 aluminum alloy have been obtained by isothermal compression tests at temperatures of 300–500 ?C and strain rates of 0.01–10 s?1. The plastic flow instability map is established based on Gegel B and Murthy instability criteria because the deformed compression samples suggest that the combination of the above two instability criteria has more comprehensive crack prediction ability. And the processing map based on Dynamic Mate-rial Model (DMM) of as-cast 7075 aluminum alloy has been developed through a superposition of the established instability map and power dissipation map. In terms of microstructure of the deformed samples and whether plastic flow is stable or not, the processing map can be divided into five areas: stable area with as-cast grain, stable area with homogeneous grain resulting from dynamic recovery, instability area with as-cast grain, instability area with the second phase and instability area with mixed grains. In consideration of microstructure characteristics in the above five areas of the processing map, the stable area with homogeneous grain resulting from dynamic recovery, namely the temperatures at 425–465 ?C and the strain rates at 0.01–1 s?1, is suggested to be suitable processing window for the as-cast 7075 aluminum alloy.

  14. Processing map of as-cast 7075 aluminum alloy for hot working

    Directory of Open Access Journals (Sweden)

    Guo Lianggang

    2015-12-01

    Full Text Available The true stress–strain curves of as-cast 7075 aluminum alloy have been obtained by isothermal compression tests at temperatures of 300–500 °C and strain rates of 0.01–10 s−1. The plastic flow instability map is established based on Gegel B and Murthy instability criteria because the deformed compression samples suggest that the combination of the above two instability criteria has more comprehensive crack prediction ability. And the processing map based on Dynamic Material Model (DMM of as-cast 7075 aluminum alloy has been developed through a superposition of the established instability map and power dissipation map. In terms of microstructure of the deformed samples and whether plastic flow is stable or not, the processing map can be divided into five areas: stable area with as-cast grain, stable area with homogeneous grain resulting from dynamic recovery, instability area with as-cast grain, instability area with the second phase and instability area with mixed grains. In consideration of microstructure characteristics in the above five areas of the processing map, the stable area with homogeneous grain resulting from dynamic recovery, namely the temperatures at 425–465 °C and the strain rates at 0.01–1 s−1, is suggested to be suitable processing window for the as-cast 7075 aluminum alloy.

  15. Effect of Low Frequency Electromagnetic Field on Macrosegregation of Horizontal Direct Chill Casting Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    Zhihao ZHAO; Jianzhong CUI; Jie DONG; Beijiang ZHANG

    2005-01-01

    The horizontal direct chill (HDC) casting process is a well-established production route for aluminum alloy ingot but the ingot may suffer from macrosegregation sometimes. In order to control the defect, a low frequency electromagnetic field has been applied in HDC casting process and the relevant influence has been studied. The results show that application of low frequency electromagnetic field can reduce macrosegregation in HDC casting process; and two main parameters of electromagnetic field density and frequency, have great influences on the solution distribution along the diameter of ingot. Moreover, the mechanisms of reduction of macrosegregation by electromagnetic field have been discussed.

  16. Casting of High-Aluminum-Content Mg Alloys Strip by a Horizontal Twin-Roll Caster

    Science.gov (United States)

    Harada, Hideto; Nishida, Shinichi; Masaki, Endo; Watari, Hisaki

    2014-04-01

    This study was aimed to investigate casting of high-aluminum-content Mg alloys strip by a horizontal twin-roll caster. A horizontal-type twin-roll caster was equipped with a nozzle. This nozzle was movable. The roll size was φ300 × W150, and copper rolls were used. The rolling road was very small. It was possible to cast AZ91D and AZ121 magnesium alloys continuously by a horizontal twin-roll caster. There was gloss and no crack. The thickness of as-cast strip of AZ91D was 4.5 mm and that of AZ121 was 4.6 mm, respectively. In the case that roll velocity was 48 m/min, the thickness of as-cast strip of AZ121 was 2.0 mm. A 2.0-mm-thick strip was able to coil, and the diameter was φ500 mm. The microstructures of the as-cast strip of AZ91D and AZ121 magnesium alloys were observed using light optical microscopy. Isometric dendrite crystals were observed at the as-cast strip. The as-cast strip without facing of AZ91D and AZ121 magnesium alloys were able to hot rolling of 75 pct reduction. The surface of the as-rolled sheet was flat and glossy. The tensile strength of the as rolled was 230 MPa and the elongation of as rolled was 4 pct.

  17. Process for Producing a Cast Article from a Hypereutectic Aluminum-Silicon Alloy

    Science.gov (United States)

    Lee, Jonathan A. (Inventor); Chen, Po-Shou (Inventor)

    2003-01-01

    A process for making a cast article from an aluminum alloy includes first casting an article from an alloy having the following composition, in weight percent: Silicon (Si) 14.0-25.0, Copper (CU) 5.5-8.0, Iron (Fe) 0-0.8, Magnesium (Mg) 0.5-1.5, Nickel (Ni) 0.05-1.2, Manganese (Mn) 0-1.0, Titanium (Ti) 0.05-1.2, Zirconium (Zr) 0.12-1.2, Vanadium (V) 0.05-1.2, Zinc (Zn) 0-0.9, Phosphorus (P) 0.001-0.1, Aluminum, balance. In this alloy the ration of Si:Mg is 15-35, and the ratio of Cu:Mg is 4-15. After an article is cast from the alloy, the cast article is aged at a temperature within the range of 400 F to 500 F for a time period within the range of four to 16 hours. It has been found especially advantageous if the cast article is first exposed to a solutionizing step prior to the aging step. This solutionizing step is carried out by exposing the cast article to a temperature within the range of 875 F to 1025 F for a time period of fifteen minutes to four hours. It has also been found to be especially advantageous if the solutionizing step is followed directly with a quenching step, wherein the cast article is quenched in a quenching medium such as water at a temperature within the range of 120 F to 300 F. The resulting cast article is highly suitable in a number of high temperature applications, such as heavy-duty pistons for internal combustion engines.

  18. Thin wall ductile iron casting as a substitute for aluminum alloy casting in automotive industry

    Directory of Open Access Journals (Sweden)

    M. Górny

    2009-01-01

    Full Text Available In paper it is presented thin wall ductile iron casting (TWDI as a substitute of aluminium alloy casting. Upper control arm made of ductile iron with wall thickness ranging from 2 – 3.7 mm was produced by inmold process. Structure, mechanical properties and computer simulations were investigated. Structural analysis of TWDI shows pearlitic-ferritic matrix free from chills and porosity. Mechanical testing disclose superior ultimate tensile strength (Rm, yield strength (Rp0,2 and slightly lower elongation (E of TWDI in comparison with forged control arm made of aluminium alloy (6061-T6. Moreover results of computer simulation of static loading for tested control arms are presented. Analysis show that the light-weight ductile iron casting can be loaded to similar working conditions as the forged Al alloy without any potential failures.

  19. Rapid air film continuous casting of aluminum alloy using static magnetic field

    Institute of Scientific and Technical Information of China (English)

    Fu QU; Huixue JIANG; Gaosong WANG; Qingfeng ZHU; Xiangjie WANG; Jianzhong CUI

    2009-01-01

    The influences of the cooling style and static magnetic field on the air film casting process were investigated. Ingots of 6063 aluminum alloy were produced by AIRSOL VEIL casting with double-layer cooling water and static magnetic field. Surface segregation, hot crack and variation of solute content along the radius direction of ingot were examined. The results showed that double-layer cooling water can improve the surface quality and avoid of hot crack, which created conditions to increase the casting speed. The electromagnetic casting process can effectively improve the surface quality in high speed casting process, and static magnetic field has a great influence on solute distribution along the radius direction of ingot.

  20. Development of a New Ferrous Aluminosilicate Refractory Material for Investment Casting of Aluminum Alloys

    Science.gov (United States)

    Yuan, Chen; Jones, Sam; Blackburn, Stuart

    2012-12-01

    Investment casting is a time-consuming, labour intensive process, which produces complex, high value-added components for a variety of specialised industries. Current environmental and economic pressures have resulted in a need for the industry to improve current casting quality, reduce manufacturing costs and explore new markets for the process. Alumino-silicate based refractories are commonly used as both filler and stucco materials for ceramic shell production. A new ceramic material, norite, is now being produced based on ferrous aluminosilicate chemistry, having many potential advantages when used for the production of shell molds for casting aluminum alloy. This paper details the results of a direct comparison made between the properties of a ceramic shell system produced with norite refractories and a typical standard refractory shell system commonly used in casting industry. A range of mechanical and physical properties of the systems was measured, and a full-scale industrial casting trial was also carried out. The unique properties of the norite shell system make it a promising alternative for casting aluminum based alloys in the investment foundry.

  1. Density and solidification feeding model of vacuum counter-pressure cast aluminum alloy under grade-pressuring conditions

    OpenAIRE

    Qing-song Yan; Huan Yu; Gang Lu

    2016-01-01

    The density of vacuum counter-pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade pressure difference and time on the density of aluminum alloys was discussed, and the solidification feeding model under grade-pressuring condition was established. The results indicate the grade-pressured solidification feeding ability of vacuum counter-pressure casting mainly depends on grade pressure difference and time. With the increase of grade pressure di...

  2. EFFECT OF CASTING MOULD ON MECHANICAL PROPERTIES OF 6063 ALUMINUM ALLOY

    Directory of Open Access Journals (Sweden)

    WASIU AJIBOLA AYOOLA

    2012-02-01

    Full Text Available Modern production methods for casting articles include the use of sand- mould, metal-mould, die, and centrifugal castings. Castings produced using sand mould is known to have peculiar microstructures depending on average size, distribution and shape of the moulding sand grains and the chemical composition of the alloy. These affect the surface finish, permeability and refractoriness of all the castings. In this paper, the effect of using CO2 process, metal mould, cement-bonded sand mould and naturally-bonded sand mould on the hardness, tensile and impact strengths of as-cast 6063 Aluminum alloy is presented. The results show that there is significant increase in hardness(33.7 HB of the alloy when naturally-bonded sand mould is used for its production over that of metal, CO2 and cement moulds. The stress-strain curves behaviour of the samples also indicated that sample from naturally bonded sand has highest tensile strength with superior ductility. The alloy shows highest impact strength when metal mould is used for sample preparation in comparison with other moulds.

  3. Metallic Reinforcement of Direct Squeeze Die Casting Aluminum Alloys for Improved Strength and Fracture Resistance

    Energy Technology Data Exchange (ETDEWEB)

    D. Schwam: J.F. Wallace: Y. Zhu: J.W. Ki

    2004-10-01

    The utilization of aluminum die casting as enclosures where internal equipment is rotating inside of the casting and could fracture requires a strong housing to restrain the fractured parts. A typical example would be a supercharger. In case of a failure, unless adequately contained, fractured parts could injure people operating the equipment. A number of potential reinforcement materials were investigated. The initial work was conducted in sand molds to create experimental conditions that promote prolonged contact of the reinforcing material with molten aluminum. Bonding of Aluminum bronze, Cast iron, and Ni-resist inserts with various electroplated coatings and surface treatments were analyzed. Also toughening of A354 aluminum cast alloy by steel and stainless steel wire mesh with various conditions was analyzed. A practical approach to reinforcement of die cast aluminum components is to use a reinforcing steel preform. Such performs can be fabricated from steel wire mesh or perforated metal sheet by stamping or deep drawing. A hemispherical, dome shaped casting was selected in this investigation. A deep drawing die was used to fabricate the reinforcing performs. The tendency of aluminum cast enclosures to fracture could be significantly reduced by installing a wire mesh of austenitic stainless steel or a punched austenitic stainless steel sheet within the casting. The use of reinforcements made of austenitic stainless steel wire mesh or punched austenitic stainless steel sheet provided marked improvement in reducing the fragmentation of the casting. The best strengthening was obtained with austenitic stainless steel wire and with a punched stainless steel sheet without annealing this material. Somewhat lower results were obtained with the annealed punched stainless steel sheet. When the annealed 1020 steel wire mesh was used, the results were only slightly improved because of the lower mechanical properties of this unalloyed steel. The lowest results were

  4. Preparation of casting alloy ZL101 with coarse aluminum-silicon alloy

    Institute of Scientific and Technical Information of China (English)

    YOU Jing; WANG Yao-wu; FENG Nai-xiang; YANG Ming-sheng

    2008-01-01

    The coarse Al-Si alloy produced by carbothermal reduction of aluminous ore contains 55% Al, 25% Si and some impurities. The main impurities are slag and iron. The process of manufacturing casting Al-Si alloy ZL101 with the coarse Al-Si alloy was studied. The phase constitution and microstructure of the coarse Al-Si alloy, slag and ZL101 were examined by X-ray diffractometry and scanning electron microscopy. The results show that the content of silicon and iron in the casting alloy reduces with the increase of the dosage of purificant and manganese, but increases with the rise of filtering temperature. It is found that casting Al-Si alloy conforming to industrial standard can be produced after refining by using purificant, and removing iron by using manganese and added magnesium.

  5. Stress ratio effects in fatigue of lost foam cast aluminum alloy 356

    Science.gov (United States)

    Palmer, David E.

    Lost foam casting is a highly versatile metalcasting process that offers significant benefits in terms of design flexibility, energy consumption, and environmental impact. In the present work, the fatigue behavior of lost foam cast aluminum alloy 356, in conditions T6 and T7, was investigated, under both zero and non-zero mean stress conditions, with either as-cast or machined surface finish. Scanning electron microscopy was used to identify and measure the defect from which fatigue fracture initiated. Based on the results, the applicability of nine different fatigue mean stress equations was compared. The widely-used Goodman equation was found to be highly non-conservative, while the Stulen, Topper-Sandor, and Walker equations performed reasonably well. Each of these three equations includes a material-dependent term for stress ratio sensitivity. The stress ratio sensitivity was found to be affected by heat treatment, with the T6 condition having greater sensitivity than the T7 condition. The surface condition (as-cast vs. machined) did not significantly affect the stress ratio sensitivity. The fatigue life of as-cast specimens was found to be approximately 60--70% lower than that of machined specimens at the same equivalent stress. This reduction could not be attributed to pore size alone, and is suspected to be due to the greater concentration of pyrolysis products at the as-cast surface. Directions for future work, including improved testing methods and some possible methods of improving the properties of lost foam castings, are discussed.

  6. Non-dendritic structural 7075 aluminum alloy byliquidus cast and its semi-solid compression behavior

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Fine, equiaxed, non-dendritic structure needed by semi-solid processing was obtained by liquidus cast, i.e.7075 wrought aluminum alloy cast from liquidus temperature. The microstructures after heat treatment at different tem-peratures and time in the semi-solid range were observed, and the compression deformation behavior at different tempera-tures (490 ~ 600 C) and strain rates (5 × 10-3 ~ 5s-1) was investigated by means of Gleeble-1500 thermal-mechenicalsimulator. Thc results show that the deformation resistance of the non-dendritic structure attained by liquidus cast in semi-solid is remarkably lower than that of conventional dendritic structure. The formability of non-dendritic structure is betterthan that of dendritic structure

  7. The influence of the parameters of lost foam process on the quality of aluminum alloys castings

    Directory of Open Access Journals (Sweden)

    Aćimović-Pavlović Zagorka

    2010-01-01

    Full Text Available This paper presents the research results of application of Lost foam process for aluminum alloys castings of a simple geometry. The process characteristic is that patterns and gating of moulds, made of polymers, stay in the mould till the liquid metal inflow. In contact with the liquid metal, pattern intensely and in relatively short time decomposes and evaporates, which is accompanied by casting crystallization. As a consequence of polymer pattern decomposition and evaporation a great quantity of liquid and gaseous products are produced, which is often the cause of different types of casting errors. This paper presents the results of a research with a special consideration given to detecting and analyzing the errors of castings. In most cases the cause of these errors are defects of polymer materials used for evaporable patterns production, as well as defects of materials for refractory coatings production for polymer patterns. The researches have shown that different types of coatings determine properties of the obtained castings. Also, the critical processing parameters (polymer pattern density, casting temperature, permeability of refractory coating and sand, construction of patterns and gating of moulds significantly affect on castings quality. During the research a special consideration was given to control and optimization of these parameters with the goal of achieving applicable castings properties. The study of surface and internal error of castings was performed systematically in order to carry out preventive measures to avoid errors and minimize production costs. In order to achieve qualitative and profitable castings production by the method of Lost foam it is necessary to reach the balance in the system: evaporable polymer pattern - liquid metal - refractory coating - sandy cast in the phase of metal inflow, decomposition and evaporation of polymer pattern, formation and solidification of castings. By optimizing the processing

  8. Density and solidification feeding model of vacuum counter-pressure cast aluminum alloy under grade-pressuring conditions

    Directory of Open Access Journals (Sweden)

    Qing-song Yan

    2016-03-01

    Full Text Available The density of vacuum counter-pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade pressure difference and time on the density of aluminum alloys was discussed, and the solidification feeding model under grade-pressuring condition was established. The results indicate the grade-pressured solidification feeding ability of vacuum counter-pressure casting mainly depends on grade pressure difference and time. With the increase of grade pressure difference, the density of all the aluminum alloy samples increases, and the trend of change in density from the pouring gate to the top location is first decreasing gradually and then increasing. In addition, in obtaining the maximum density, the optimal grade-pressuring time is different for samples with different wall thicknesses, and the solidification time when the solid volume fraction of aluminum alloy reaches about 0.65 appears to be the optimal beginning time for grade-pressuring.

  9. The Influence of Silicon Content on Recrystallization of Twin-Roll Cast Aluminum Alloys for Heat Exchangers

    OpenAIRE

    Poková, Michaela; Cieslar, Miroslav; Lacaze, Jacques

    2012-01-01

    International audience Thin foils of aluminum alloys are commonly used in automotive industry for manufacturing heat exchangers. Use of twin-roll casting instead of direct-chill casting requires modifications in the manufacturing process and use of improved materials. In the present study, the evolution in microstructure and mechanical properties during isochronal annealing of two AW3003-based alloys differing in silicon content was monitored. The silicon influenced both the microhardness ...

  10. Effect of centrifugal counter-gravity casting on solidification microstructure and mechanical properties of A357 aluminum alloy

    OpenAIRE

    Li Xinlei; Hao Qitang; Miao Xiaochuan

    2014-01-01

    To investigate the influence of Centrifugal Counter-gravity Casting (C3) process on the solidification microstructure and mechanical properties of the casting, A357 aluminum alloy samples were produced by different process conditions under C3. The results show that C3 has better feeding capacity compared with the vacuum suction casting; and that the mechanical vibration and the convection of melts formed at the centrifugal rotation stage suppress the growth of dendrites, subsequently resultin...

  11. Processing map of as-cast 7075 aluminum alloy for hot working

    OpenAIRE

    Guo Lianggang; Yang Shuang; Yang He; Zhang Jun

    2015-01-01

    The true stress–strain curves of as-cast 7075 aluminum alloy have been obtained by isothermal compression tests at temperatures of 300–500 °C and strain rates of 0.01–10 s−1. The plastic flow instability map is established based on Gegel B and Murthy instability criteria because the deformed compression samples suggest that the combination of the above two instability criteria has more comprehensive crack prediction ability. And the processing map based on Dynamic Material Model (DMM) of as-c...

  12. Cerium-Based, Intermetallic-Strengthened Aluminum Casting Alloy: High-Volume Co-product Development

    Science.gov (United States)

    Sims, Zachary C.; Weiss, D.; McCall, S. K.; McGuire, M. A.; Ott, R. T.; Geer, Tom; Rios, Orlando; Turchi, P. A. E.

    2016-07-01

    Several rare earth elements are considered by-products to rare earth mining efforts. By using one of these by-product elements in a high-volume application such as aluminum casting alloys, the supply of more valuable rare earths can be globally stabilized. Stabilizing the global rare earth market will decrease the long-term criticality of other rare earth elements. The low demand for Ce, the most abundant rare earth, contributes to the instability of rare earth extraction. In this article, we discuss a series of intermetallic-strengthened Al alloys that exhibit the potential for new high-volume use of Ce. The castability, structure, and mechanical properties of binary, ternary, and quaternary Al-Ce based alloys are discussed. We have determined Al-Ce based alloys to be highly castable across a broad range of compositions. Nanoscale intermetallics dominate the microstructure and are the theorized source of the high ductility. In addition, room-temperature physical properties appear to be competitive with existing aluminum alloys with extended high-temperature stability of the nanostructured intermetallic.

  13. Characterization of Phases in an As-cast Copper-Manganese-Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    J.Iqbal, F.Hasan; F.Ahmad

    2006-01-01

    Copper-manganese-aluminum (CMA) alloys, containing small additions of Fe, Ni, and Si, exhibit good strength and remarkable corrosion resistance against sea water. The alloys are used in as-cast condition, and their microstructure can show wide variations. The morphology, crystallography and composition of the phases presented in an as-cast (CMA) alloy of nominal composition Cu-14%Mn-8%Al-3%Fe-2%Ni were investigated using optical, electron optical, and microprobe analytical techniques. The as-cast microstructure consisted of the grains of fcc α and bcc β-phases alongwith intermetallic precipitates of various morphologies. The dendritic-shaped particles and the cuboid-shaped precipitates, which were rich in Fe and Mn and had an fcc DO3 structure. These four different morphologies of intermetallic precipitates exhibited discrete orientationrelationships with the α-matrix. The β-grains only contained very small cuboid shaped precipitates, which could only be resolved through transmission electron microscopy. These precipitates were found to be based on Fe3Al and had the DO3 structure.

  14. Gating system optimization of low pressure casting A356 aluminum alloy intake manifold based on numerical simulation

    Directory of Open Access Journals (Sweden)

    Jiang Wenming

    2014-03-01

    Full Text Available To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on filling and solidification processes of the casting was carried out using the ProCAST software. The gating system of the casting is optimized according to the simulation results. Results show that when the gating system consists of only one sprue, the filling of the molten metal is not stable; and the casting does not follow the sequence solidification, and many shrinkage porosities are observed through the casting. After the gating system is improved by adding one runner and two in-gates, the filling time is prolonged from 4.0 s to 4.5 s, the filling of molten metal becomes stable, but this casting does not follow the sequence solidification either. Some shrinkage porosity is also observed in the hot spots of the casting. When the gating system was further improved by adding risers and chill to the hot spots of the casting, the shrinkage porosity defects were eliminated completely. Finally, by using the optimized gating system the A356 aluminum alloy intake manifold casting with integrated shape and smooth surface as well as dense microstructure was successfully produced.

  15. Application of a criterion for cold cracking to casting high strength aluminum alloys

    NARCIS (Netherlands)

    Lalpoor, M.; Eskin, D.G.; Fjaer, H.G.; Ten Cate, A.; Ontijt, N.; Katgerman, L.

    2010-01-01

    Direct chill (DC) casting of high strength 7xxx series aluminium alloys is difficult mainly due to solidification cracking (hot cracks) and solid state cracking (cold cracks). Poor thermal properties along with extreme brittleness in the as-cast condition make DC-casting of such alloys a challenging

  16. High strength aluminum cast alloy: A Sc modification of a standard Al–Si–Mg cast alloy

    International Nuclear Information System (INIS)

    A standard Aluminum–Silicon–Magnesium cast alloy (A357 foundry alloy without Beryllium) modified with different weight percentages of Scandium (Sc), has been studied to evaluate the effects of Sc contents on microstructure and strength. Study has been conducted under optimized parameters of melting, casting and heat treatment. Characterization techniques like optical microscopy, SEM, TEM and tensile testing were employed to analyze the microstructure and mechanical properties. Results obtained in this research indicate that with the increase of Sc contents up to 0.4 wt%, grain size is decreased by 80% while ultimate tensile strength and hardness are increased by 28% and 19% respectively. Moreover along with the increase in strength, elongation to failure is also increased up to 165%. This is quite interesting behavior because usually strength and ductility have inverse relationship

  17. Physico-chemical characteristic of aluminum alloy castings manufactured with cores containing fly ash as a base material

    OpenAIRE

    A. Baliński

    2008-01-01

    Castings were poured from PA9 aluminum alloy. Cores in the form of standard cylindrical specimens were made from the core mixture based on fly ash of the identified chemical and granular composition. The binder for the fly ash-based core mixture was chemically modified, hydrated sodium silicate. From the ready test castings, specimens were cut out for metallographic examinations and evaluation of morphology in the examined microregions. The structure was examined under a NEOPHOT 32 metallogra...

  18. Casting technique for light metal alloy

    International Nuclear Information System (INIS)

    Light metal alloys such as aluminum, magnesium, zinc and etc. can be produced in the various forms by casting technique. The casting technique for aluminum is classified as mold casting either using a sand mold or permanent mold; or both. Aluminum alloys casting are the most versatile of all common foundry alloys and generally have the highest castability ratings. Aluminum is adaptable to many of the commonly used casting methods and can be readily cast in metal molds. This work is attempted to investigate the availability and reliability of casting technique in obtaining of finish product. (Author)

  19. Centerline Depletion in Direct-Chill Cast Aluminum Alloys: The Avalanche Effect and Its Consequence for Turbulent Jet Casting

    Science.gov (United States)

    Wagstaff, Samuel R.; Allanore, Antoine

    2016-07-01

    Avalanche dynamics of sedimenting grains in direct-chill casting of aluminum ingots is investigated as a primary driving force for centerline segregation. An analytical model predicting the importance of avalanche events as a function of casting parameters is proposed and validated with prior art results. New experimental results investigating the transient and steady-state centerline segregation of DC casting with a turbulent jet are reported.

  20. Application of a criterion for cold cracking to casting high strength aluminum alloys

    OpenAIRE

    Lalpoor, M; Eskin, D G; Fjaer, H.G.; Ten Cate, A.; Ontijt, N.; Katgerman, L.

    2010-01-01

    Direct chill (DC) casting of high strength 7xxx series aluminium alloys is difficult mainly due to solidification cracking (hot cracks) and solid state cracking (cold cracks). Poor thermal properties along with extreme brittleness in the as-cast condition make DC-casting of such alloys a challenging process. Therefore, a criterion that can predict the catastrophic failure and cold cracking of the ingots would be highly beneficial to the aluminium industry. The already established criteria are...

  1. EFFECT OF CASTING MOULD ON MECHANICAL PROPERTIES OF 6063 ALUMINUM ALLOY

    OpenAIRE

    WASIU AJIBOLA AYOOLA; SAMSON OLUROPO ADEOSUN; OLUJIDE SAMUEL SANNI; AKINLABI OYETUNJI

    2012-01-01

    Modern production methods for casting articles include the use of sand- mould, metal-mould, die, and centrifugal castings. Castings produced using sand mould is known to have peculiar microstructures depending on average size, distribution and shape of the moulding sand grains and the chemical composition of the alloy. These affect the surface finish, permeability and refractoriness of all the castings. In this paper, the effect of using CO2 process, metal mould, cement-bonded sand mould and ...

  2. Effect of low-frequency electromagnetic field on the as-cast microstructure of a new super high strength aluminum alloy by horizontal continuous casting

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The super high strength aluminum alloy ingots with 100 mm in diameter were cast by the process of low-frequency electromagnetic horizontal continuous casting (LFEHC) and the effect of electromagnetic field on the as-cast microstructure was studied. Results show that microstructure of the sample prepared by the LFEHC process was greatly refined. Microstructures at the border and the center of the ingots were fine, uniform and rosette-shaped.Electromagnetic frequency plays a key role in microstructure refining. Fine and uniform microstructures can be obtained with optimal electromagnetic frequency. In this experiment, under a frequency of 30 Hz the microstructure was the finest and the most uniform.

  3. Effect of low-frequency electromagnetic field on the as-cast microstructure of a new super high strength aluminum alloy by horizontal continuous casting

    Directory of Open Access Journals (Sweden)

    Yubo ZUO

    2005-02-01

    Full Text Available The super high strength aluminum alloy ingots with 100 mm in diameter were cast by the process of low-frequency electromagnetic horizontal continuous casting (LFEHC and the effect of electromagnetic field on the as-cast microstructure was studied. Results show that microstructure of the sample prepared by the LFEHC process was greatly refined. Microstructures at the border and the center of the ingots were fine, uniform and rosette-haped.Electromagnetic frequency plays a key role in microstructure refining. Fine and uniform microstructures can be obtained with optimal electromagnetic frequency. In this experiment, under a frequency of 30 Hz the microstructure was the finest and the most uniform.

  4. Density and solidiifcation feeding model of vacuum counter-pressure cast aluminum alloy under grade-pressuring conditions

    Institute of Scientific and Technical Information of China (English)

    Qing-song Yan; Huan Yu; Gang Lu; Bo-wen Xiong; Suai Xu

    2016-01-01

    The density of vacuum counter-pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade pressure difference and time on the density of aluminum aloys was discussed, and the solidiifcation feeding model under grade-pressuring condition was established. The results indicate the grade-pressured solidiifcation feeding ability of vacuum counter-pressure casting mainly depends on grade pressure difference and time. With the increase of grade pressure difference, the density of al the aluminum aloy samples increases, and the trend of change in density from the pouring gate to the top location is first decreasing gradually and then increasing. In addition, in obtaining the maximum density, the optimal grade-pressuring time is different for samples with different wal thicknesses, and the solidiifcation time when the solid volume fraction of aluminum aloy reaches about 0.65 appears to be the optimal beginning time for grade-pressuring.

  5. Effect of centrifugal counter-gravity casting on solidification microstructure and mechanical properties of A357 aluminum alloy

    Directory of Open Access Journals (Sweden)

    Li Xinlei

    2014-01-01

    Full Text Available To investigate the influence of Centrifugal Counter-gravity Casting (C3 process on the solidification microstructure and mechanical properties of the casting, A357 aluminum alloy samples were produced by different process conditions under C3. The results show that C3 has better feeding capacity compared with the vacuum suction casting; and that the mechanical vibration and the convection of melts formed at the centrifugal rotation stage suppress the growth of dendrites, subsequently resulting in the refinement of grains and the improvement of mechanical properties, density and hardness. A finer grain and higher strength can be obtained in the A357 alloy by increasing centrifugal radius and rotational speed. However, casting defects will appear near the rotational axis and the mechanical properties will decrease once the rotational speed exceeds 150 r·min-1.

  6. DEFINITION OF THE CASTING MECHANISMS OF ALUMINUM-SILICON ALLOYS WITH SUPERFINE AND INVERTED MICROSTRUCTURE

    Directory of Open Access Journals (Sweden)

    V. Yu. Stetsenko

    2013-01-01

    Full Text Available The basic mechanisms of Al-Si alloysmodifying are determined. Fast solidification and inheritance modification are major in casting of alloys with a highly dispersed and inverted microstructure.

  7. Casting of aluminum-copper based alloy by controlled diffusion solidification

    Directory of Open Access Journals (Sweden)

    Li Fan

    2015-03-01

    Full Text Available A quaternary alloy (Al-5.0Cu-0.35Mn-0.25Ti, wt.%, having a similar chemical component with ZL205A, was prepared using a controlled diffusion solidification (CDS process and a conventional casting process. The effect of the casting process on microstructure and hardness was investigated. The grain morphology and casting defects of the alloy prepared via the conventional casting and CDS were observed and compared at various pouring temperatures. Results show that the CDS process can alleviate the hot tearing defects and reduce the density of porosity, while getting rid of the riser that is generally used for feeding during conventional casting. Structure observations show that the grain morphology of the conventional cast alloy is mainly dendritic, and the grain size decreases when the pouring temperature is decreased, while the CDS cast alloy consists of a large number of spherical grains, which can decrease the thermal cracking tendency and segregation defect, and enhance the hardness of the alloy.

  8. Some properties of aluminum-uranium alloys in the cast, rolled and annealed conditions

    International Nuclear Information System (INIS)

    The metallographic and hardness changes associated with the rolling and subsequent. annealing of aluminum alloys containing up to 30-wt.% uranium have been described. The alloys possessed good rolling properties. However the richer alloys were unusual in that after an initial reduction,, further cold rolling caused softening. In the alloy range examined, increasing uranium contents caused reduced preferred orientation. Qualitative explanations have been proposed to account for the observations on roll softening and preferred orientation. Heat-treating and ageing experiments confirmed that the solid solubility of uranium in aluminum is negligible. (author)

  9. Effect of iron-intermetallics and porosity on tensile and impact properties of aluminum-silicon-copper and aluminum-silicon-magnesium cast alloys

    Science.gov (United States)

    Ma, Zheyuan

    Aluminum-silicon (Al-Si) alloys are an important class of materials that constitute the majority of aluminum cast parts produced, due to their superior properties and excellent casting characteristics. Within this family of alloys, Al-Si-Cu and Al-Si-Mg cast alloys are frequently employed in automotive applications. The commercially popular 319 and 356 alloys, representing these two alloy systems, were selected for study in the present work, with the aim of investigating the effect of iron intermetallics and porosity on the alloy performance. This was carried out through a study of the tensile and impact properties, these being two of the important mechanical properties used in design calculations. Iron, through the precipitation of second phase intermetallic constituents, in particular the platelike beta-Al5FeSi phase, is harmful to the alloy properties. Likewise, gas- or shrinkage porosity in castings is also detrimental to the mechanical properties. By determining the optimum alloying, melt processing and solidification parameters (viz., Fe content, Sr modification and cooling rate) required to minimize the harmful effects of porosity and iron intermetallics, and studying their role on the fracture behavior, the fracture mechanism in the alloys could be determined. Castings were prepared from both industrial and experimental 319.2, B319.2 and A356.2 alloy melts, containing Fe levels of 0.2--1.0 wt%. Sr-modified (˜200 ppm) melts were also prepared for each alloy Fe level. The end-chilled refractory mold used provided directional solidification and a range of cooling rates (or dendrite arm spacings, DAS) within the same casting. Tensile and impact test samples machined from specimen blanks sectioned from the castings at various heights above the chill end provided DASs of 23--85mum. All samples were T6-heat-treated before testing. Tests were carried out employing Instron Universal and Instrumented Charpy testing machines. Optical microscopy, image analysis, SEM

  10. Effect of hot and cold deformation on the recrystallization texture of continuous cast AA 5052 aluminum alloy

    International Nuclear Information System (INIS)

    The effect of different relative amounts of hot and cold deformation on the recrystallization texture of a continuous cast AA 5052 aluminum alloy was investigated by X-ray diffraction. The results show that hot deformation promotes the cube and Goss components at the expense of the r-cube and remainder components. The formation of the R component does not appear to be affected by hot and cold deformation

  11. Effect of hot and cold deformation on the recrystallization texture of continuous cast AA 5052 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.C. [Department of Chemical and Materials Engineering, University of Kentucky, 177 Anderson Hall, Lexington, KY 40506 (United States)]. E-mail: wcliu@engr.uky.edu; Man, C.-S. [Department of Mathematics, University of Kentucky, 715 Patterson Office Tower, Lexington, KY 40506 (United States); Raabe, D. [Max-Planck-Institut fuer Eisenforschung, Microstructure Physics, Max-Planck-Str. 1, 40237, Duesseldorf (Germany); Morris, J.G. [Department of Chemical and Materials Engineering, University of Kentucky, 177 Anderson Hall, Lexington, KY 40506 (United States)

    2005-12-15

    The effect of different relative amounts of hot and cold deformation on the recrystallization texture of a continuous cast AA 5052 aluminum alloy was investigated by X-ray diffraction. The results show that hot deformation promotes the cube and Goss components at the expense of the r-cube and remainder components. The formation of the R component does not appear to be affected by hot and cold deformation.

  12. Microstructure and Mechanical Properties of MWCNTs Reinforced A356 Aluminum Alloys Cast Nanocomposites Fabricated by Using a Combination of Rheocasting and Squeeze Casting Techniques

    Directory of Open Access Journals (Sweden)

    Abou Bakr Elshalakany

    2014-01-01

    Full Text Available A356 hypoeutectic aluminum-silicon alloys matrix composites reinforced by different contents of multiwalled carbon nanotubes (MWCNTs were fabricated using a combination of rheocasting and squeeze casting techniques. A novel approach by adding MWCNTs into A356 aluminum alloy matrix with CNTs has been performed. This method is significant in debundling and preventing flotation of the CNTs within the molten alloy. The microstructures of nanocomposites and the interface between the aluminum alloy matrix and the MWCNTs were examined by using an optical microscopy (OM and scanning electron microscopy (SEM equipped with an energy dispersive X-ray analysis (EDX. This method remarkably facilitated a uniform dispersion of nanotubes within A356 aluminum alloy matrix as well as a refinement of grain size. In addition, the effects of weight fraction (0.5, 1.0, 1.5, 2.0, and 2.5 wt% of the CNT-blended matrix on mechanical properties were evaluated. The results have indicated that a significant improvement in ultimate tensile strength and elongation percentage of nanocomposite occurred at the optimal amount of 1.5 wt% MWCNTs which represents an increase in their values by a ratio of about 50% and 280%, respectively, compared to their corresponding values of monolithic alloy. Hardness of the samples was also significantly increased by the addition of CNTs.

  13. Semi-solid thixo casting structure of aluminum alloy and relevant assistant analysis with the help of computer simulation

    Institute of Scientific and Technical Information of China (English)

    Yi-tao YANG; Jian-fu WANG; Meng CHEN; Heng-hua ZHANG; Guang-jie SHAO

    2008-01-01

    The relationship between structure morphology of semi-solid aluminum alloy die-casting sample and filling condition was studied. By systematical structure analysis and computer simulation of the filling process, the quant-itative relationship between microscopic morphology (such as solid fraction, grain size and shape) and formation state was studied. The results showed that the billet microstruc-ture must have fine and round grains for the die-casting of complex shapes. It is necessary to optimize injection speeds to escape the non-uniform distribution of the solid fraction in complex and changeable mold cavity.

  14. Rotary bending fatigue behavior of A356 –T6 aluminum alloys by vacuum pressurizing casting

    Directory of Open Access Journals (Sweden)

    Yong-qin Liu

    2015-09-01

    Full Text Available Vacuum pressurizing casting technique, providing better mould filling and inter-dendritic feeding, can reduce the porosity greatly in cast aluminum alloys, and improve the fatigue properties. The rotary bending fatigue properties of A356-T6 alloys prepared by vacuum pressurizing casting were investigated. The S-N curve and limit strength 90 MPa under fatigue life of 107 cycles were obtained. The analyses on the fatigue fractography and microstructure of specimens showed that the fatigue fracture mainly occurs at the positions with casting defects in the subsurface, especially at porosities regions, which attributed to the crack propagation during the fatigue fracture process. Using the empirical crack propagation law of Pairs-Erdogon, the quantitative relationship among the initial crack size, fatigue life and applied stress was established. The fatigue life decreases with an increase in initial crack size. Two constants in the Pairs-Erdogon equation of aluminum alloy A356-T6 were calculated using the experimental data.

  15. Instability of the Liquid Metal-Pattern Interface in the Lost Foam Casting of Aluminum Alloys

    Science.gov (United States)

    Griffiths, W. D.; Ainsworth, M. J.

    2016-06-01

    The nature of the liquid metal-pattern interface during mold filling in the Lost Foam casting of aluminum alloys was investigated using real-time X-ray radiography for both normal expanded polystyrene, and brominated polystyrene foam patterns. Filling the pattern under the action of gravity from above or below had little effect on properties, both cases resulting in a large scatter of tensile strength values, (quantified by their Weibull Modulus). Countergravity filling at different velocities demonstrated that the least scatter of tensile strength values (highest Weibull Modulus) was associated with the slowest filling, when a planar liquid metal-pattern interface occurred. Real-time X-ray radiography showed that the advancing liquid metal front became unstable above a certain critical velocity, leading to the entrainment of the degrading pattern material and associated defects. It has been suggested that the transition of the advancing liquid metal-pattern interface into an unstable regime may be a result of Saffman-Taylor Instability.

  16. The Effect of Applied Pressure During Feeding of Critical Cast Aluminum Alloy Components With Particular Reference to Fatigue Resistance

    Energy Technology Data Exchange (ETDEWEB)

    J.T. Berry; R. Luck; B. Zhang; R.P. Taylor

    2003-06-30

    the medium to long freezing range alloys of aluminum such as A356, A357, A206, 319 for example are known to exhibit dispersed porosity, which is recognized as a factor affecting ductility, fracture toughness, and fatigue resistance of light alloy castings. The local thermal environment, for example, temperature gradient and freezing from velocity, affect the mode of solidification which, along with alloy composition, heat treatment, oxide film occlusion, hydrogen content, and the extent to which the alloy contracts on solidification, combine to exert strong effects on the porosity formation in such alloys. In addition to such factors, the availability of liquid metal and its ability to flow through the partially solidified casting, which will be affect by the pressure in the liquid metal, must also be considered. The supply of molten metal will thus be controlled by the volume of the riser available for feeding the particular casting location, its solidification time, and its location together with any external pressure that might be applied at the riser.

  17. Cast Aluminum Alloys for High Temperature Applications Using Nanoparticles Al2O3 and Al3-X Compounds (X = Ti, V, Zr)

    Science.gov (United States)

    Lee, Jonathan A.

    2009-01-01

    In this paper, the effect of nanoparticles Al2O3 and Al3-X compounds (X = Ti, V, Zr) on the improvement of mechanical properties of aluminum alloys for elevated temperature applications is presented. These nanoparticles were selected based on their low cost, chemical stability and low diffusions rates in aluminum at high temperatures. The strengthening mechanism at high temperature for aluminum alloy is based on the mechanical blocking of dislocation movements by these nanoparticles. For Al2O3 nanoparticles, the test samples were prepared from special Al2O3 preforms, which were produced using ceramic injection molding process and then pressure infiltrated by molten aluminum. In another method, Al2O3 nanoparticles can also be homogeneously mixed with fine aluminum powder and consolidated into test samples through hot pressing and sintering. With the Al3-X nanoparticles, the test samples are produced as precipitates from in-situ reactions with molten aluminum using conventional permanent mold or die casting techniques. It is found that cast aluminum alloy using nanoparticles Al3-X is the most cost effective method to produce high strength aluminum alloys for high temperature applications in comparison to nanoparticles Al2O3. Furthermore, significant mechanical properties retention in high temperature environment could be achieved with Al3-X nanoparticles, resulting in tensile strength of nearly 3 times higher than most 300- series conventional cast aluminum alloys tested at 600 F.

  18. Influence of Sludge Particles on the Tensile Properties of Die-Cast Secondary Aluminum Alloys

    Science.gov (United States)

    Ferraro, Stefano; Timelli, Giulio

    2015-04-01

    The effects of sludge intermetallic particles on the mechanical properties of a secondary AlSi9Cu3(Fe) die-casting alloy have been studied. Different alloys have been produced by systematically varying the Fe, Mn, and Cr contents within the composition tolerance limits of the standard EN AC-46000 alloy. The microstructure shows primary α-Al x (Fe,Mn,Cr) y Si z sludge particles, with polyhedral and star-like morphologies, although the presence of primary β-Al5FeSi phase is also observed at the highest Fe:Mn ratio. The volume fraction of primary compounds increases as the Fe, Mn, and Cr contents increase and this can be accurately predicts from the Sludge Factor by a linear relationship. The sludge amount seems to not influence the size and the content of porosity in the die-cast material. Furthermore, the sludge factor is not a reliable parameter to describe the mechanical properties of the die-cast AlSi9Cu3(Fe) alloy, because this value does not consider the mutual interaction between the elements. In the analyzed range of composition, the design of experiment methodology and the analysis of variance have been used in order to develop a semi-empirical model that accurately predicts the mechanical properties of the die-cast AlSi9Cu3(Fe) alloys as function of Fe, Mn, and Cr concentrations.

  19. Physico-chemical characteristic of aluminum alloy castings manufactured with cores containing fly ash as a base material

    Directory of Open Access Journals (Sweden)

    A. Baliński

    2008-07-01

    Full Text Available Castings were poured from PA9 aluminum alloy. Cores in the form of standard cylindrical specimens were made from the core mixture based on fly ash of the identified chemical and granular composition. The binder for the fly ash-based core mixture was chemically modified, hydrated sodium silicate. From the ready test castings, specimens were cut out for metallographic examinations and evaluation of morphology in the examined microregions. The structure was examined under a NEOPHOT 32 metallographic microscope using metallographic polished sections etched and unetched. For the specimen surface morphology evaluation a STEREOSCAN 420 scanning electron microscope and SE1 detector were used. The X-ray microanalysis was made on an EDS LINK ISIS 300 microanalyser. The fly ash was observed to have no major effect on the structure and chemical composition of castings.

  20. Evolution of Intermetallic Phases in Soldering of the Die Casting of Aluminum Alloys

    Science.gov (United States)

    Song, Jie; Wang, Xiaoming; DenOuden, Tony; Han, Qingyou

    2016-06-01

    Most die failures are resulted from chemical reactions of dies and molten aluminum in the die casting of aluminum. The formation of intermetallic phases between a steel die and molten aluminum is investigated by stationary immersion tests and compared to a real die casting process. Three intermetallic phases are identified in the stationary immersion tests: a composite layer and two compact layers. The composite layer is a mixture of α bcc, Al, and Si phases. The α bcc phase changes in morphology from rod-like to spherical shape, while the growth rate of the layer changes from parabolic to linear pattern with immersion time. The first compact layer forms rapidly after immersion and maintains a relatively constant thickness. The second compact layer forms after 4 hours of immersion and exhibits parabolic growth with immersion time. In comparison, only a composite layer and the first compact layer are observed in a real die casting process. The fresh molten aluminum of high growth rate washes away the second intermetallic layer easily.

  1. Experimental Observation and Analytical Modeling of Melting and Solidification during Aluminum Alloy Repair by Turbulence Flow Casting

    Directory of Open Access Journals (Sweden)

    Muki Satya Permana

    2015-10-01

    Full Text Available This paper presents an overview on the state of the art of applicable casting technology for applications in the field of repairing aluminum alloy components. Repair process on the Al alloy sample using similar metal has been carried out to investigate the micro-structural effect. Joining occurs as a result of convection heat transfer of molten flow into the sand mold which melts the existing base metal inside the mold and subsequent solidification. The analytical model has been developed to describe aluminum alloy component repair by turbulence flow casting. The model is designed based on heat transfer principle that can handle the phenomena of heat flow. The experimental result and analytical model analyses pointed out that joint quality are greatly affected by parameters of preheating temperature and duration of molten metal flow in the mold. To obtain a desired metallurgical sound at the joint, the optimum temperature and time were adjusted in order to obtain a similarity of microstructure between filler and base metal. This model is aimed to predict the use of the process parameter ranges in order to have the optimum parameters when it is applied to the experiment. The fixed parameters are flow rate, sand ratio, and pouring temperature. The process parameters are preheating temperature and pouring time. It is concluded that analytical modeling has good agreement with the experimental result.

  2. A computational study of low-head direct chill slab casting of aluminum alloy AA2024

    Science.gov (United States)

    Hasan, Mainul; Begum, Latifa

    2016-04-01

    The steady state casting of an industrial-sized AA2024 slab has been modeled for a vertical low-head direct chill caster. The previously verified 3-D CFD code is used to investigate the solidification phenomena of the said long-range alloy by varying the pouring temperature, casting speed and the metal-mold contact heat transfer coefficient from 654 to 702 °C, 60-180 mm/min, and 1.0-4.0 kW/(m2 K), respectively. The important predicted results are presented and thoroughly discussed.

  3. Crystallization characteristics of cast aluminum alloys during a unidirectional solidification process

    International Nuclear Information System (INIS)

    The crystal orientation characteristics of cast Al–Si, Al–Cu and Al–Mg alloys produced by a unidirectional solidification process are examined. Two distinct crystal orientation patterns are observed: uniform and random formation. A uniform crystal orientation is created by columnar growth of α-Al dendrites in the alloys with low proportions of alloying element, e.g., the Al–Si alloy (with Si <12.6%) and the Al–Cu and Al–Mg alloys (with Cu and Mg <2%). A uniformly organized crystal orientation with [100] direction is created by columnar growth of α-Al dendrites. With increasing proportion of alloying element (>2% Cu or Mg), the uniform crystal orientations collapse in the Al–Cu and Al–Mg alloys, owing to interruption of the columnar α-Al dendrite growth as a result of different dynamics of the alloying atoms and the creation of a core for the eutectic phases. For the hypo-eutectic Al–Si alloys, a uniform crystal orientation is obtained. In contrast, a random orientation can be detected in the hyper-eutectic Al–Si alloy (15% Si), which results from interruption of the growth of the α-Al dendrites due to precipitation of primary Si particles. There is no clear effect of crystal formation on ultimate tensile strength (UTS), whereas crystal orientation does influence the material ductility, with the alloys with a uniform crystal orientation being elongated beyond their UTS points and with necking occurring in the test specimens. In contrast, the alloys with a nonuniform crystal orientation are not elongated beyond their UTS points

  4. Crystallization characteristics of cast aluminum alloys during a unidirectional solidification process

    Energy Technology Data Exchange (ETDEWEB)

    Okayasu, Mitsuhiro, E-mail: mitsuhiro.okayasu@utoronto.ca; Takeuchi, Shuhei

    2015-05-01

    The crystal orientation characteristics of cast Al–Si, Al–Cu and Al–Mg alloys produced by a unidirectional solidification process are examined. Two distinct crystal orientation patterns are observed: uniform and random formation. A uniform crystal orientation is created by columnar growth of α-Al dendrites in the alloys with low proportions of alloying element, e.g., the Al–Si alloy (with Si <12.6%) and the Al–Cu and Al–Mg alloys (with Cu and Mg <2%). A uniformly organized crystal orientation with [100] direction is created by columnar growth of α-Al dendrites. With increasing proportion of alloying element (>2% Cu or Mg), the uniform crystal orientations collapse in the Al–Cu and Al–Mg alloys, owing to interruption of the columnar α-Al dendrite growth as a result of different dynamics of the alloying atoms and the creation of a core for the eutectic phases. For the hypo-eutectic Al–Si alloys, a uniform crystal orientation is obtained. In contrast, a random orientation can be detected in the hyper-eutectic Al–Si alloy (15% Si), which results from interruption of the growth of the α-Al dendrites due to precipitation of primary Si particles. There is no clear effect of crystal formation on ultimate tensile strength (UTS), whereas crystal orientation does influence the material ductility, with the alloys with a uniform crystal orientation being elongated beyond their UTS points and with necking occurring in the test specimens. In contrast, the alloys with a nonuniform crystal orientation are not elongated beyond their UTS points.

  5. Effect of Sr-modification on the bendability of cast aluminum alloy A356 using digital image correlation method

    International Nuclear Information System (INIS)

    The effect of cast microstructure on bendability of automotive cast aluminum alloy A356 has been studied by machining sheet specimens and conducting V-bend tests. Specimens in the loaded condition are observed from the through-thickness section using a CCD camera and also using a scanning electron microscope (SEM). The latter allowed recording of high magnification images from the through-thickness region of the bend to determine aspects of strain localization and particle induced damage in the microstructure. In addition, the initial microstructure is utilized as a speckle pattern for further analysis of through-thickness strain development in the bent region using digital image correlation (DIC) method. The method is applied to unmodified and Sr-modified A356 compositions. The results indicate superior bendability of Sr modified A356 alloy compared to the unmodified alloy. The differences in bendability are attributed to the size and morphology of eutectic Si phase particles that undergo significant cracking in the tensile region of specimen during bending. The results demonstrate that high magnification SEM imaging of bent specimens coupled with DIC based strain analysis offers a useful method of analyzing the effect of microstructure on bendability of cast materials

  6. Effects of rare earth Er additions on microstructure development and mechanical properties of die-cast ADC12 aluminum alloy

    International Nuclear Information System (INIS)

    Highlights: ► The α-Al dendrite and the eutectic Si were significantly refined by adding Er. ► The Hv of alloys first increased with increasing Er content, then decreases. ► The UTS of alloys increased with addition of Er, but the EL decreased. - Abstract: The effects of rare earth erbium (Er) additions (0, 0.3, 0.6 and 0.9 wt.%) on the microstructure development and tensile properties of die-cast ADC12 aluminum alloy have been investigated in the present work. The microstructures and fracture surfaces of die-cast samples were examined by optical microscopy and scanning electron microscopy (SEM). It was found that the secondary dendrite arm spacing (SDAS) will decrease with increasing Er content, as the Er content increases to 0.6%, the lowest SDAS was obtained. In addition, the Er modified the eutectic silicon from a coarse plate-like and acicular structure to a fine branched and fibrous one. The microhardness of die-casted alloys were measured, the microhardness corresponding to the die-casted samples with 0, 0.3, 0.6 and 0.9 wt.% Er additions are 100.6, 107.1, 113.6 and 108.5 Hv, respectively. The tensile properties were improved by the addition of Er, and a good ultimate tensile strength (269 MPa) but poor elongation (2%) were obtained when the Er addition was 0.6 wt.%. Furthermore, fractographic examinations revealed that refined pore and spheroidized α-Al dendrite were responsible for the high ultimate tensile strength.

  7. Effect of non uniform void size and shape distributions on deformation failure in cast aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jun Su; Kang, Dong Hwan; Kim, Tae Won; Bae, Dae Sung [Hanyang Univ., Seoul (Korea, Republic of); Yoon, Hyung Sop [Hyundai Kia Motors R and D Division, Hwaseong (Korea, Republic of)

    2012-07-15

    Tensile tests were conducted on several cast aluminum specimens with different degrees of porosity. The effects of non uniform void size and shape distributions, including spherical and non spherical types, on stress-strain behavior resulting from different initiation mechanisms were investigated. A micro mechanics based statistical approach was employed, and the heterogeneous microstructures could therefore be modeled during the deformation process. The predicted changes of the distributions of void size and void shape generally agreed with experimental results. Void spatial variation was also quantified, and its effects on the level of failure were analyzed. The void spatial variation facilitated development of inhomogeneous deformation, which results in failure.

  8. Precise Analysis of Microstructural Effects on Mechanical Properties of Cast ADC12 Aluminum Alloy

    Science.gov (United States)

    Okayasu, Mitsuhiro; Takeuchi, Shuhei; Yamamoto, Masaki; Ohfuji, Hiroaki; Ochi, Toshihiro

    2015-04-01

    The effects of microstructural characteristics (secondary dendrite arm spacing, SDAS) and Si- and Fe-based eutectic structures on the mechanical properties and failure behavior of an Al-Si-Cu alloy are investigated. Cast Al alloy samples are produced using a special continuous-casting technique with which it is easy to control both the sizes of microstructures and the direction of crystal orientation. Dendrite cells appear to grow in the casting direction. There are linear correlations between SDAS and tensile properties (ultimate tensile strength σ UTS, 0.2 pct proof strength σ 0.2, and fracture strain ɛ f). These linear correlations, however, break down, especially for σ UTS vs SDAS and ɛ f vs SDAS, as the eutectic structures become more than 3 μm in diameter, when the strength and ductility ( σ UTS and ɛ f) decrease significantly. For eutectic structures larger than 3 μm, failure is dominated by the brittle eutectic phases, for which SDAS is no longer strongly correlated with σ UTS and ɛ f. In contrast, a linear correlation is obtained between σ 0.2 and SDAS, even for eutectic structures larger than 3 μm, and the eutectic structure does not have a strong effect on yield behavior. This is because failure in the eutectic phases occurs just before final fracture. In situ failure observation during tensile testing is performed using microstructural and lattice characteristics. From the experimental results obtained, models of failure during tensile loading are proposed.

  9. 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.

  10. Application of a Pore Fraction Hot Tearing Model to Directionally Solidified and Direct Chill Cast Aluminum Alloys

    Science.gov (United States)

    Dou, Ruifeng; Phillion, A. B.

    2016-08-01

    Hot tearing susceptibility is commonly assessed using a pressure drop equation in the mushy zone that includes the effects of both tensile deformation perpendicular to the thermal gradient as well as shrinkage feeding. In this study, a Pore Fraction hot tearing model, recently developed by Monroe and Beckermann (JOM 66:1439-1445, 2014), is extended to additionally include the effect of strain rate parallel to the thermal gradient. The deformation and shrinkage pore fractions are obtained on the basis of the dimensionless Niyama criterion and a scaling variable method. First, the model is applied to the binary Al-Cu system under conditions of directional solidification. It is shown that for the same Niyama criterion, a decrease in the cooling rate increases both the deformation and shrinkage pore fractions because of an increase in the time spent in the brittle temperature region. Second, the model is applied to the industrial aluminum alloy AA5182 as part of a finite element simulation of the Direct Chill (DC) casting process. It is shown that an increase in the casting speed during DC casting increases the deformation and shrinkage pore fractions, causing the maximum point of pore fraction to move towards the base of the casting. These results demonstrate that including the strain rate parallel to the thermal gradient significantly improves the predictive quality of hot tearing criteria based on the pressure drop equation.

  11. The effect of solidification rate on the growth of small fatigue cracks in a cast 319-type aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Caton, M.J.; Jones, J.W.; Boileau, J.M.; Allison, J.E.

    1999-12-01

    A study was conducted to investigate the effect of solidification rate on the growth behavior of small fatigue cracks in a 319-type aluminum alloy, a common Al-Si-Cu alloy used in automotive castings. Fatigue specimens were taken from cast material that underwent a hot isostatic pressing (HIP) process in order to eliminate shrinkage pores and to facilitate the observation of surface-initiated cracks by replication. Naturally initiated surface cracks ranging in length from 17 {micro}m to 2 mm were measured using a replication technique. Growth rates of the small cracks were calculated as a function of the elastic stress-intensity-factor range ({Delta}K). Long-crack growth-rate data (10 mm {le} length {le} 25 mm) were obtained from compact-tension (CT) specimens, and comparison to the small-crack data indicates the existence of a significant small-crack effect in this alloy. The solidification rate is shown to have a significant influence on small-crack growth behavior, with faster solidification rates resulting in slower growth rates at equivalent {Delta}K levels. A stress-level effect is also observed for both solidification rates, with faster growth rates occurring at higher applied-stress amplitudes at a given {Delta}K. A crack-growth relation proposed by Nisitani and others is modified to give reasonable correlation of small-crack growth data to different solidification rates and stress levels.

  12. The effect of solidification rate on the growth of small fatigue cracks in a cast 319-type aluminum alloy

    Science.gov (United States)

    Caton, M. J.; Jones, J. Wayne; Boileau, J. M.; Allison, J. E.

    1999-12-01

    A study was conducted to investigate the effect of solidification rate on the growth behavior of small fatigue cracks in a 319-type aluminum alloy, a common Al-Si-Cu alloy used in automotive castings. Fatigue specimens were taken from cast material that underwent a hot isostatic pressing (HIP) process in order to eliminate shrinkage pores and to facilitate the observation of surface-initiated cracks by replication. Naturally initiated surface cracks ranging in length from 17 µm to 2 mm were measured using a replication technique. Growth rates of the small cracks were calculated as a function of the elastic stress-intensity-factor range (Δ K). Long-crack growth-rate data (10 mm≤length≤25 mm) were obtained from compact-tension (CT) specimens, and comparison to the small-crack data indicates the existence of a significant small-crack effect in this alloy. The solidification rate is shown to have a significant influence on small-crack growth behavior, with faster solidification rates resulting in slower growth rates at equivalent Δ K levels. A stress-level effect is also observed for both solidification rates, with faster growth rates occurring at higher applied-stress amplitudes at a given Δ K. A crack-growth relation proposed by Nisitani and others is modified to give reasonable correlation of small-crack growth data to different solidification rates and stress levels.

  13. Solidification, growth mechanisms, and associated properties of aluminum-silicon and magnesium lightweight casting alloys

    Science.gov (United States)

    Hosch, Timothy Al

    Continually rising energy prices have inspired increased interest in weight reduction in the automotive and aerospace industries, opening the door for the widespread use and development of lightweight structural materials. Chief among these materials are cast Al-Si and magnesium-based alloys. Utilization of Al-Si alloys depends on obtaining a modified fibrous microstructure in lieu of the intrinsic flake structure, a process which is incompletely understood. The local solidification conditions, mechanisms, and tensile properties associated with the flake to fiber growth mode transition in Al-Si eutectic alloys are investigated here using bridgman type gradient-zone directional solidification. Resulting microstructures are examined through quantitative image analysis of two-dimensional sections and observation of deep-etched sections showing three-dimensional microstructural features. The transition was found to occur in two stages: an initial stage dominated by in-plane plate breakup and rod formation within the plane of the plate, and a second stage where the onset of out-of-plane silicon rod growth leads to the formation of an irregular fibrous structure. Several microstructural parameters were investigated in an attempt to quantify this transition, and it was found that the particle aspect ratio is effective in objectively identifying the onset and completion velocity of the flake to fiber transition. The appearance of intricate out-of-plane silicon instability formations was investigated by adapting a perturbed-interface stability analysis to the Al-Si system. Measurements of silicon equilibrium shape particles provided an estimate of the anisotropy of the solid Si/liquid Al-Si system and incorporation of this silicon anisotropy into the model was found to improve prediction of the instability length scale. Magnesium alloys share many of the benefits of Al-Si alloys, with the added benefit of a 1/3 lower density and increased machinability. Magnesium castings

  14. Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Lost Foam Thin Wall - Feasibility of Producing Lost Foam Castings in Aluminum and Magnesium Based Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Fasoyinu, Yemi [CanmetMATERIALS; Griffin, John A. [University of Alabama - Birmingham

    2014-03-31

    With the increased emphasis on vehicle weight reduction, production of near-net shape components by lost foam casting will make significant inroad into the next-generation of engineering component designs. The lost foam casting process is a cost effective method for producing complex castings using an expandable polystyrene pattern and un-bonded sand. The use of un-bonded molding media in the lost foam process will impose less constraint on the solidifying casting, making hot tearing less prevalent. This is especially true in Al-Mg and Al-Cu alloy systems that are prone to hot tearing when poured in rigid molds partially due to their long freezing range. Some of the unique advantages of using the lost foam casting process are closer dimensional tolerance, higher casting yield, and the elimination of sand cores and binders. Most of the aluminum alloys poured using the lost foam process are based on the Al-Si system. Very limited research work has been performed with Al-Mg and Al-Cu type alloys. With the increased emphasis on vehicle weight reduction, and given the high-strength-to-weight-ratio of magnesium, significant weight savings can be achieved by casting thin-wall (≤ 3 mm) engineering components from both aluminum- and magnesium-base alloys.

  15. Machinability Study of Stir Cast Hypoeutectic Aluminum-Silicon Alloys During Turning

    Science.gov (United States)

    Sood, P. K.; Sehgal, Rakesh; Dwivedi, D. K.

    2013-02-01

    The influence of Be and Cd (iron correctors) on mechanical properties and machining behavior of hypoeutectic Al-Si alloy (Al-7Si-0.5Mg-1.2Fe) processed by conventional and semi-solid metal (SSM) processing (stir casting) techniques is investigated. The alloys under investigation were prepared by controlling melt in an induction melting furnace. The stirring of SSM was carried out at a constant stirring speed of 400 rpm under constant cooling conditions from liquidus temperature. The turning operations were carried out under dry conditions on a CNC turning center using coated-carbide insert by varying cutting speed, feed rate, depth of cut, and approaching angle. An orthogonal array, the signal-to-noise ratio, and analysis of variance were employed to study the machining performance characteristics. The results indicate that Be/Cd modification of the alloy and selected cutting parameters significantly affect the machining characteristics. The feed rate, cutting speed, and Cd as an iron corrector have more effect on the machining behavior of the alloys under study.

  16. The Comparison of the Microstructure and Corrosion Resistance of Sand Cast Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Dobkowska A.

    2016-03-01

    Full Text Available The influence of different types of precipitation on the corrosion behavior was investigated in three aluminum-siliconmagnesium alloys. The microstructures of the alloys were studied through optical (OM and scanning electron microscopy (SEM. The structures consisted of an α-Al solid solution matrix, Si eutectic crystals, secondary phases AlFeSi and AlMgFeSi (Chinese script, as well as Mg2Si. The corrosion behavior was examined with the use of a potentiodynamic polarization test followed by a SEM surface analysis. The results indicate that all the analyzed samples were in the passive state and AlSi10Mg was less reactive in the corrosive environment.

  17. EFFECT OF LOW-FREQUENCY ELECTROMAGNETIC FIELD ON THE AS-CASTING MICROSTRUCTURES AND MECHANICAL PROPERTIES OF HDC 2024 ALUMINUM ALLOY

    Institute of Scientific and Technical Information of China (English)

    Q.F.Zhu; Z.H.Zhao; J.Z.Cui; Y.B.Zuo; F.Qu

    2008-01-01

    The influences of the low frequency electromagnetic field on the horizontal direct chill casting process were investigated experimentally. Ingots of 2024 aluminum alloy with a cross size of 40 mm×200 mm were produced by the conventional horizontal chill casting process and low frequency electromagnetic horizontal chill casting processrespectively. The as-cast structures and the mechanical property of the ingots were examined. The results showed that the low frequency electromagnetic field could substantially refine the microstructures and pronouncedly reduce the macrosegregation in the horizontal direct chill casting process. Moreover, the surface quality of the ingot was prominently improved by the low frequency electromagnetic field. The fracture strength and elongation percentage of the ingot was increased with the low frequency electromagnetic field.

  18. CHIP MORPHOLOGY AND HOLE SURFACE TEXTURE IN THE DRILLING OF CAST ALUMINUM ALLOYS. (R825370C057)

    Science.gov (United States)

    The effects of cutting fluid and other process variables on chip morphology when drilling cast aluminium alloys are investigated. The effects of workpiece material, speed, feed, hole depth, cutting-fluid presence and percentage oil concentration, workpiece temperature, drill t...

  19. Effect of hot and cold deformation on the P {0 1 1} recrystallization texture in a continuous cast Al-Mn-Mg aluminum alloy

    International Nuclear Information System (INIS)

    The effect of different relative amounts of hot and cold deformation on the P {0 1 1} recrystallization texture in a continuous cast Al-Mn-Mg aluminum alloy was investigated by X-ray diffraction. The results show that at a given total rolling strain the sheet with a high hot rolling strain exhibits a significantly stronger P texture than the sheet with a low hot rolling strain. Hot deformation strongly promotes the formation of the P texture during recrystallization annealing

  20. Casting of aluminum alloy strip using an unequal diameter twin roll caster

    Directory of Open Access Journals (Sweden)

    T. Haga

    2008-02-01

    Full Text Available Purpose: of this paper is to clear the property and ability of an unequal diameter twin roll caster to castcommercial size strip. Therefore, 400mm-width strip was cast as first step. Surface-condition, microstructure andmechanical property of the strip was investigated.Design/methodology/approach: Method used in the present study was an unequal diameter twin roll caster.This method was devised to realize easy operation of the twin roll casting and increase of casting speed.Findings: are that 400-width-strip of 3084, 5182 and 6022 could be cast at speed of 20 m/min. This strip wasabout 4 mm-thick. There were some defects on the surface. As cast strip could be cold-rolled down to sheetof 1 mm-thick. 180 degrees bending test was operated on the 6022 sheet after T4 heat treatment. Crack did notoccurred at the outer surface when strip was bent at width-direction.Research limitations/implications: is that the quantity of the melt was 21kg and investigation of theproperties was not enough for practical use. The larger weight of melt must be cast for production.Practical implications: are as below. The 400mm-width strip can be cast easily by the unequal diameter twinroll caster. This caster can be adapted to 3083, 5182 and 6022.Originality/value: as below. The economy sheet with 400mm width can be produced by the unequal diameter twinroll caster. 3083, 5182 and 6022 can be cast at the speed of 20m/min. The thickness of the strip was about 4mm.

  1. Development of a 3D Filling Model of Low-Pressure Die-Cast Aluminum Alloy Wheels

    Science.gov (United States)

    Duan, Jianglan; Maijer, Daan; Cockcroft, Steve; Reilly, Carl

    2013-12-01

    A two-phase computational fluid dynamics model of the low-pressure die-cast process for the production of A356 aluminum alloy wheels has been developed to predict the flow conditions during die filling. The filling model represents a 36-deg section of a production wheel, and was developed within the commercial finite-volume package, ANSYS CFX, assuming isothermal conditions. To fully understand the behavior of the free surface, a novel technique was developed to approximate the vent resistances as they impact on the development of a backpressure within the die cavity. The filling model was first validated against experimental data, and then was used to investigate the effects of venting conditions and pressure curves during die filling. It was found that vent resistance and vent location strongly affected die filling time, free surface topography, and air entrainment for a given pressure fill-curve. With regard to the pressure curve, the model revealed a strong relation between the pressure curve and the flow behavior in the hub, which is an area prone to defect formation.

  2. A comparison of the aging kinetics of a cast alumina-6061 aluminum composite and a monolithic 6061 aluminum alloy.

    OpenAIRE

    Hafley, Johanna L.

    1989-01-01

    Electrical resistivity and hardness measurements were conducted during isothermal aging treatments of an alumina particulate reinforced 6061 aluminum metal matrix composite and a monolithic 6061 aluminum control material. Transmission electron microscopy was utilized to examine the microstructural changes accompanying the changes in the resistivity of the monolithic during aging. In addition, differential scanning calorimetry was used to investigate the growth kinetics and thermal stability o...

  3. Numerical simulation for mold-filling of thin-walled aluminum alloy castings in traveling magnetic field

    OpenAIRE

    Wu, Shiping; Bangsheng LI; Guo, Jingjie

    2004-01-01

    The numeical simulation for mold-filling of thin-walled aluminum alloy castins in horizontal traveling magnetic field is performed. A force model of Al alloy melt in the traveling magnetic field is founded by analyzing traveling magnetic field carefully. Numerical model of Al alloy mold-filling is founded based on N-S equation, which was suitable for traveling magnetic field. By using acryl glass mold with indium as alloy melt, the experiment testiied the filling state of alloy in traveling m...

  4. Low-aluminum content iron-aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Goodwin, G.M.; Alexander, D.J. [and others

    1995-06-01

    The low-aluminum-content iron-aluminum program deals with the development of a Fe-Al alloy with aluminum content such as a produce the minimum environmental effect at room temperature. The FAPY is an Fe-16 at. % Al-based alloy developed at the Oak Ridge National Laboratory as the highest aluminum-containing alloy with essentially no environmental effect. The chemical composition for FAPY in weight percent is: aluminum = 8.46, chromium = 5.50, zirconium = 0.20, carbon = 0.03, molybdenum = 2.00, yttrium = 0.10 and iron = 83.71. The ignots of the alloy can be hot worked by extrusion, forging, and rolling processes. The hot-worked cast structure can be cold worked with intermediate anneals at 800{degrees}C. Typical room-temperature ductility of the fine-grained wrought structure is 20 to 25% for this alloy. In contrast to the wrought structure, the cast ductility at room temperature is approximately 1% with a transition temperature of approximately 100 to 150{degrees}C, above which ductility values exceed 20%. The alloy has been melted and processed into bar, sheet, and foil. The alloy has also been cast into slabs, step-blocks of varying thicknesses, and shapes. The purpose of this section is to describe the welding response of cast slabs of three different thicknesses of FAPY alloy. Tensile, creep, and Charpy-impact data of the welded plates are also presented.

  5. Aluminum-zinc alloy squeeze casting technological parameters optimization based on PSO and ANN

    Directory of Open Access Journals (Sweden)

    SHU Fu-hua

    2007-08-01

    Full Text Available This paper presents a kind of ZA27 squeeze casting process parameter optimization method using artificial neural network (ANN combined with the particle swarm optimizer (PSO. Regarding the test data as samples and using neural network create ZA27 squeeze casting process parameters and mechanical properties of nonlinear mapping model. Using PSO optimize the model and obtain the optimum value of the process parameters. Make full use of the non-neural network mapping capabilities and PSO global optimization capability. The network uses the radial direction primary function neural network, using the clustering and gradient method to make use of network learning, in order to enhance the generalization ability of the network. PSO takes dynamic changing inertia weights to accelerate the convergence speed and avoid a local minimum.

  6. Aluminum-zinc alloy squeeze casting technological parameters optimization based on PSO and ANN

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper presents a kind of ZA27 squeeze casting process parameter optimization method using artificial neural network (ANN) combined with the particle swarm optimizer (PSO). Regarding the test data as samples and using neural network create ZA27 squeeze casting process parameters and mechanical properties of nonlinear mapping model. Using PSO optimize the model and obtain the optimum value of the process parameters. Make full use of the non-neural network mapping capabilities and PSO global optimization capability. The network uses the radial direction primary function neural network, using the clustering and gradient method to make use of network learning, in order to enhance the generalization ability of the network. PSO takes dynamic changing inertia weights to accelerate the convergence speed and avoid a local minimum.

  7. Plunger Kinematic Parameters Affecting Quality of High-Pressure Die-Cast Aluminum Alloys

    Science.gov (United States)

    Fiorese, Elena; Bonollo, Franco

    2016-07-01

    The selection of the optimal process parameters in high-pressure die casting has been long recognized as a complex problem due to the involvement of a large number of interconnected variables. Among these variables, the effect of the plunger motion has been proved to play a prominent role, even if a thorough and exhaustive study is still missing in the literature. To overcome this gap, this work aims at identifying the most relevant plunger kinematic parameters and estimates their correlation with the casting quality, by means of a statistically significant sample manufactured with different plunger motion profiles. In particular, slow and fast shot velocities and switching position between two stages have been varied randomly in accordance with design of experiment methodology. The quality has been assessed through the static mechanical properties and porosity percentage. As a further proof, the percentage of oxides has been estimated on the fracture surfaces. These measurements have been correlated to novel parameters, representing the mechanical energy and the inertial force related to the plunger motion, that have been extracted from the time-history of the displacement curves. The application of statistical methods demonstrates that these novel parameters accurately explain and predict the overall quality of castings.

  8. Manufacturing of Aluminum Composite Material Using Stir Casting Process

    OpenAIRE

    Jokhio, Muhammad Hayat; Panhwer, Muhammad Ibrahim; Unar, Mukhtiar Ali

    2016-01-01

    Manufacturing of aluminum alloy based casting composite materials via stir casting is one of the prominent and economical route for development and processing of metal matrix composites materials. Properties of these materials depend upon many processing parameters and selection of matrix and reinforcements. Literature reveals that most of the researchers are using 2, 6 and 7xxx aluminum matrix reinforced with SiC particles for high strength properties whereas, insufficient information is ava...

  9. Manufacturing of Aluminum Composite Material Using Stir Casting Process

    OpenAIRE

    Muhammad Hayat Jokhio; Muhammad Ibrahim Panhwar; Mukhtiar Ali Unar

    2011-01-01

    Manufacturing of aluminum alloy based casting composite materials via stir casting is one of the prominent and economical route for development and processing of metal matrix composites materials. Properties of these materials depend upon many processing parameters and selection of matrix and reinforcements. Literature reveals that most of the researchers are using 2, 6 and 7xxx aluminum matrix reinforced with SiC particles for high strength properties whereas, insufficient inf...

  10. Microstructure-properties correlation of pressure die cast eutectic aluminum-silicon alloys for escalator steps (Part I)

    International Nuclear Information System (INIS)

    This paper is a study of the roles of strontium as a modifier and titanium as a refiner of the Al-12%Si commercial alloy for escalator steps processed by a hot-chamber pressure-die casting method. Specifically, two objectives were pursued. First, the detection of the level at which the modifier and the refiner become effective in altering the relevant microstructural parameters, namely, the volume fraction, grain size and shape of proeutectic phases. Second, investigation of the morphology of the eutectic matrix

  11. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  12. Synthesis and characterization of in situ formed titanium diboride particulate reinforced AA7075 aluminum alloy cast composites

    International Nuclear Information System (INIS)

    Highlights: ► Fabrication of AA7075/TiB2 AMC by in situ reaction K2TiF6 and KBF4 salts. ► Most of the TiB2 particles were located in inter granular regions. ► Uniform distribution of TiB2 particles having clear interface and good bonding. ► TiB2 particles displayed various shapes such as cubic, spherical and hexagonal. ► TiB2 particles enhanced the mechanical properties of the AMC. -- Abstract: In situ fabrication of aluminum matrix composites (AMCs) has gathered widespread attention of researchers due to inherent advantages over ex situ methods. Aluminum alloy AA7075 reinforced with various amounts (0, 3, 6 and 9 wt.%) of TiB2 particles were prepared by the in situ reaction of inorganic salts such as K2TiF6 and KBF4 to molten aluminum. X-ray diffraction patterns of the prepared AMCs clearly revealed the formation of TiB2 particles without the presence of any other intermetallic compounds. The microstructures of the AMCs were studied using optical and scanning electron microscopy. The in situ formed TiB2 particles were characterized with uniform distribution, clear interface, good bonding and various shapes such as cubic, spherical and hexagonal. The formation of TiB2 particles enhanced the microhardness and ultimate tensile strength (UTS) of the AMCs.

  13. Effects of deformation temperature and rate on compressive deformation behaviour of Y 112 die cast aluminum alloy in semi-solid state

    Institute of Scientific and Technical Information of China (English)

    YANG Ming-bo; HU Hong-jun; TANG Li-wen; DAI Bing

    2006-01-01

    The semi-solid compression deformation behaviour of Y112 die casting aluminum alloy with nondendritic structure obtained under the semi-solid isothermal treatment condition of 570 ℃ and 120 min, was investigated by means of Gleeble-1500 thermal-mechanical simulator. The results show that, when the strain is lower than 0.8, along with the compression strain increasing,the compression stress firstly increases rapidly, then decreases gradually. Under the condition of different deformation temperatures and deformation rates, the maximium compression stress is obtained simultaneously when the strain is 0.07 approximately.Furthermore, when the deformation rate keeps a constant, the compression stress decreases along with the deformation temperature increasing, and when the deformation temperature keeps a constant, the compression stress increases along with the deformation rate increasing.

  14. Mechanical properties and constitutive behaviors of as-cast 7050 aluminum alloy from room temperature to above the solidus temperature

    Science.gov (United States)

    Bai, Qing-ling; Li, Hong-xiang; Du, Qiang; Zhang, Ji-shan; Zhuang, Lin-zhong

    2016-08-01

    The mechanical properties and constitutive behaviors of as-cast AA7050 in both the solid and semi-solid states were determined using the on-cooling and in situ solidification approaches, respectively. The results show that the strength in the solid state tends to increase with decreasing temperature. The strain rate plays an important role in the stress-strain behaviors at higher temperatures, whereas the influence becomes less pronounced and irregular when the temperature is less than 250°C. The experimental data were fitted to the extended Ludwik equation, which is suitable to describe the mechanical behavior of the materials in the as-cast state. In the semi-solid state, both the strength and ductility of the alloy are high near the solidus temperature and decrease drastically with decreasing solid fraction. As the solid fraction is less than 0.97, the maximum strength only slightly decreases, whereas the post-peak ductility begins to increase. The experimental data were fitted to the modified creep law, which is used to describe the mechanical behavior of semi-solid materials, to determine the equivalent parameter f GBWL, i.e., the fraction of grain boundaries covered by liquid phase.

  15. High speed twin roll casting of 6061 alloy strips

    OpenAIRE

    T. Haga; H. Sakaguchi; Watari, H; S. Kumai

    2008-01-01

    Purpose: of this paper is to clear the possibility of high speed roll casting of thin strips of two aluminum alloys:6061 and recycled 6061. Mechanical properties of the roll cast 6061 and recycled 6061 strips were investigated inthe frame of this purpose.Design/methodology/approach: Methods used in the present study were high speed twin roll caster and lowtemperature casting. These methods were used to realize rapid solidification and increase the casting speed.Findings: are that 6061 and rec...

  16. 铝合金砂型低压铸造浇注系统的选择与设计%Choice and Design of Gating System of Sand Mold Low-pressure Casting for Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    佘瑞平; 赵拴勃; 千斌; 段昭; 曲媛

    2013-01-01

    低压铸造是目前获得优质铝合金铸件的有力手段之一.本文立足于低压铸造生产实践经验,结合低压铸造原理,对不同结构、材质(糊状凝固或顺序凝固模式)类型的铝合金铸件砂型低压铸造浇注系统的选择与设计进行了系统的归纳和总结.实践证明,所归纳总结的结果对铝合金低压铸造工艺设计具有一定参考作用.%The low-pressure foundry is one of the emollient means for acquiring a high-quality aluminum alloy castings currently. Based on fulfillment experience of casting production at die low pressure and combining low pressure casting principle. The choice and design of the aluminum alloy castings with different structures, and different material (paste form solidify or in proper order solidify mode) structure and sand type for the low-pressure foundry system were summaried. The research results have singificant effects on the design of aluminum alloy low-pressure casting process

  17. Aluminum alloy impact sparkling

    Directory of Open Access Journals (Sweden)

    M. Dudyk

    2008-08-01

    Full Text Available The cast machine parts are widely used in many branches of industry. A very important issue is gaining the appropriate knowledge relating to the application of castings in places of explosion risks including but not limited to mining, chemical industry and rescue works. A possibility of explosion risks occurrence following the impact sparkling of the cast metal parts is still not solved problem in scientific research. In relation to this issue, in this article, the results of the study are presented, and relating to the tendency to impact sparkling of the aluminium alloys used in machine building. On the grounds of the results obtained, it was demonstrated that the registered impact sparkles bunches of feathers from the analyzed alloys: AlSi7Mg, (AK7; AlSi9Mg, (AK9; AlSi6Cu4, (AK64 and AlSi11, (AK11 show significant differences between each other. The quantitative analysis of the temperature distribution and nuclei surface area performed on the example of the alloy AK9 (subjected to defined period of corrosion allows for the statement that they are dangerous in conditions of explosion risk. Following this fact, designers and users of machine parts made from these materials should not use them in conditions where the explosive mixtures occur.

  18. ''Heat Transfer at the Mold-Metal Interface in Permanent Mold Casting of Aluminum Alloys'' Final Project Report; FINAL

    International Nuclear Information System (INIS)

    This project on heat transfer coefficients in metal permanent mold casting has been conducted in three areas. They are the theoretical study at the University of Michigan, the experimental investigation of squeeze casting at CMI-Tech Center (Now Hayes-Lemmerz Technical Center) and the experimental investigation of low pressure permanent mold casting at Amcast Automotive

  19. Standard digital reference images for inspection of aluminum castings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 These digital reference images illustrate the types and degrees of discontinuities that may be found in aluminum-alloy castings. The castings illustrated are in thicknesses of 1/ 4 in. [6.35 mm] and 3/4 in. [19.1mm]. 1.2 All areas of this standard may be open to agreement between the cognizant engineering organization and the supplier, or specific direction from the cognizant engineering organization. These items should be addressed in the purchase order or the contract. 1.3 The values stated in inch-pound units are to be regarded as standard. 1.4 These digital reference images are not intended to illustrate the types and degrees of discontinuities found in aluminum-alloy castings when performing film radiography. If performing film radiography of aluminum-alloy castings, refer to Reference Radiographs E 155. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and he...

  20. Effects of low-frequency magnetic field on grain boundary segregation in horizontal direct chill casting of 2024 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Effects of low frequency electromagnetic field on grain boundary segregation in horizontal direct chill (HDC)casting process was investigated experimentally. The grain boundary segregation and microstructures of the ingots,which manufactured by conventional HDC casting and low frequency electromagnetic HDC casting were compared.Results show that low frequency electromagnetic field significantly refines the microstructures and reduces grain boundary segregation. Decreasing electromagnetic frequency or increasing electromagnetic intensity has great effects in reducing grain boundary segregation. Meanwhile, the governing mechanisms were discussed.

  1. Effect of low frequency electromagnetic field on microstructures and macrosegregation of horizontal direct chill casting aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    赵志浩; 崔建忠; 董杰; 张海涛; 张北江

    2004-01-01

    The influences of low frequency electromagnetic field on cast surface, microstructures and macrosegregation in horizontal direct chill(HDC) casting process were investigated experimentally. The cast surfaces, microstructures and macrosegregation of the ingots manufactured by conventional HDC and low frequency electromagnetic HDC casting were compared. The results show that low frequency electromagnetic field significantly improves the surface quality, refines the microstructures and reduces macrosegregation. Further more, increasing electromagnetic intensity or decreasing frequency is beneficial to the improvement. In the range of ampere-turns and frequency employed in the experiments, the optimum ampere-turns is found to be 10 000 A · turn and the frequency to be 30 Hz.

  2. Analysis of chemical composition of cast aluminum alloy by spark source atomic emission spectrometry%火花源原子发射光谱法分析铸铝合金的化学成分

    Institute of Scientific and Technical Information of China (English)

    刘博涛; 谢宝强; 于洋

    2009-01-01

    The chemical composition of ZAL cast-aluminum alloy was comprehensively analyzed by spark source atomic emission spectrometry.The working conditions of instrument such as the precombustion time, integration time and cleaning time of electrode were optimized.The appropriate two-spot standardized samples were used to find the calibration method for the simultaneous determination of chemical composition in ZAL cast-aluminum alloy.The proposed method was applied to the determination of Cu, Mn, Zn, Pb, Mg, Sn, Fe, Cr, Ni, Ti and Si in cast-aluminum alloy.The results were in good agreement with the certified values.%用火花源原子发射光谱仪对ZAL铸铝合金的化学成分进行全分析.通过实验确定了予燃时间、积分时间、对电极清理时间等最佳的仪器工作条件,并在最佳工作条件下,选取了适宜的两点标准化试样,给出了适合ZAL铸铝合金中化学成分同时测定的校准方案.所建立的方法应用于铸铝合金中Cu,Mn,Zn,Pb,Mg,Sn,Fe,Cr,Ni,Ti,Si等元素的测定,测得结果与认定值一致.

  3. Laminate squeeze casting of carbon fiber reinforced aluminum matrix composites

    International Nuclear Information System (INIS)

    Highlights: • Laminate squeeze casting shortens infiltration distance to half the fabric thickness. • Oxide scale on aluminum sheets serves as initial carbon–aluminum diffusion barrier. • Liquid infiltrates fiber fabrics from their respective neighboring aluminum layers. • Hydrostatic pressure in molten aluminum preserves the laminate configuration. • A good carbon fiber–aluminum matrix interface bond is achieved. - Abstract: Carbon fiber reinforced aluminum matrix composites show an excellent combination of lightweight, mechanical properties, ease of processing and low costs. However, standard liquid infiltration squeeze casting often requires complex preforms in order to control fiber configuration and distribution. It also requires relatively high pressures to overcome the pressure drop across the preform, which can lead to preform compaction and damage and can limit the maximum component thickness that can be thoroughly infiltrated. Therefore, a laminate squeeze casting process is investigated as alternative whereby alternate layers of fiber fabrics and aluminum sheets are hot consolidated. Liquid infiltrates the fiber fabrics from their two respective neighboring aluminum layers, thereby reducing the infiltration distance from the entire component height to only half the thickness of individual fiber layers. This results in a rapid and thorough infiltration. Composites with fiber contents between 7 and 14 vol% are successfully fabricated. Despite complete melting of the aluminum layers at 850 °C, optical and scanning electron microscopy investigations show that hydrostatic pressure practically preserves the laminate configuration during fabrication and no fiber agglomeration occurs. The composites show good fiber–matrix bonding. No noticeable fiber damage is observed despite some carbide formation primarily at interfaces. A composite hardness over 50% higher compared to the reference 6061 matrix alloy is achieved at a carbon fiber content of 7

  4. Effect of Ablation Casting on Microstructure and Casting Properties of A356 Aluminium Casting Alloy

    Institute of Scientific and Technical Information of China (English)

    V.Bohlooli; M.Shabani Mahalli; S.M.A.Boutorabi

    2013-01-01

    Recently the Ablation Casting Technology was invented as a new casting process to improve foundry products quality.In this study,the effects of processing variables on the porosity content,microstructure and feedability of A356 casting alloy were investigated.Secondary dendrite arm spacing (SDAS) and eutectic silicon morphologies were studied to evaluate the influence of Ablation Casting on the microstructure.Casting density was measured in order to identify porosity content and feedability of ablated and non-ablated specimens.In addition,solidification behavior of the samples was investigated by using thermal analysis technique.The cooling curves and the first derivative curves were plotted and compared with each other.Results showed the ablation process could increase solidification rate significantly.In addition,the microstructural evidences revealed that Ablation Casting process results in more fine and homogeneous structure compared to the nonablated casting.The feedability improved,SDAS reduced to 35% and porosity content decreased to 3.84 vol.% by implementing this process.It concluded the Ablation Casting is an effective process to gain higher quality in aluminum foundry.

  5. 高压开关设备中铝合金铸造工艺发展综述%General Description of the Technological Development of Aluminum Alloy Casting in High-voltage Switchgear

    Institute of Scientific and Technical Information of China (English)

    张猛; 陈丽芬

    2011-01-01

    笔者通过高压开关设备产品中铸造工艺几十年的发展过程,叙述了中国高压开关行业的铸造专业发展史,体现了中国的改革开放给企业及技术人员带来的挑战及机遇,并使铸造专业技术人员有了对高压开关设备产品中铸造铝合金零件的铸造工艺设计开始了从无到有、逐步发展、壮大的一种探索过程.总结了铸造铝硅合金不同类型零件的铸造工艺设计要点、发展应用过程,同时指出了其以后的发展方向.%Through the several decades of development of casting technology in high-voltage switchgear, this paper narrated the developing history of casting industry of Chinese high-voltage switchgear field, indicated the challenge and opportunities China's reform had brought to Chinese enterprises and technicians. Furthermore, it made the casting professional technicians starting the exploration for the casting technology of casting aluminum alloy components in high-voltage switchgear industry from preliminary stage to mature stage. Moreover, it summarized the key points of the casting technological design and developing application process of different types of components of casting aluminum silicon alloy, and also pointed out the future development trends.

  6. Mensuration and simulation of mold filling process in semi-solid die-cast of aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    YANG Yi-tao; WANG Jian-fu; ZHANG Heng-hua; SHAO Guang-jie

    2006-01-01

    To understand the flow trace of semi-solid slurry in mold cavity, some thermocouples were inserted in mold cavity, and the reaction timing of thermocouples showed the arrival of fluid. The filling time and rate were estimated by comparison between the experiment and calculation. The introduction of computer simulation technique based on ADSTEFAN was to predict injectionforming process and to prevent defects during trial manufacture of various parts. By comparing the formed appearance of parts in experiment and in simulation, and observing the relationship between internal defects inspected by X-ray or microscope and the flow field obtained in simulation, it was indicated that both have quite good agreement in simulation and experiment. Right predictions for cast defects resulted from mold filling can be carried out and proper direction was also proposed. The realization of numerical visualization for filling process during semi-solid die-cast process will play an important role in optimizing technology plan.

  7. A study on the effect of coating's sorption capacity on the porosity in lost foam aluminum alloy casting

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Effects of coating constituent, coating density, coating layer thickness and temperature on coating sorption capacity for polystyrene decomposition products have been studied systematically. It has been found that the effect of attapulgite clay on sorption capacity is the largest among coating constituents. The sorption capacity of the coating with 2 %attapulgite clay is elevated by 81%. The relationship between casting porosity and coating sorption capacity has been studied. It has been pointed out that higher coating sorption capacity for polystyrene decomposition products is helpful to decrease the casting porosity. Results also show that the sorption capacity of self- developed HW- 1 coating for polystyrene decomposition products is as good as that of Ashland coating from America.

  8. High speed twin roll casting of 6061 alloy strips

    Directory of Open Access Journals (Sweden)

    T. Haga

    2008-05-01

    Full Text Available Purpose: of this paper is to clear the possibility of high speed roll casting of thin strips of two aluminum alloys:6061 and recycled 6061. Mechanical properties of the roll cast 6061 and recycled 6061 strips were investigated inthe frame of this purpose.Design/methodology/approach: Methods used in the present study were high speed twin roll caster and lowtemperature casting. These methods were used to realize rapid solidification and increase the casting speed.Findings: are that 6061 and recycled 6061 could be cast at speed of 60 m/min. Casted strips were about 3 mmthick. As cast strip could be cold-rolled down to sheet of 1 mm thick. 180 degrees bending test was operated on thesheet after T4 heat treatment and crack was not worse than 6022 which is typical aluminum alloy for sheet of theautomobile. This result means the roll cast 6061 can be used as a sheet for body of the automobile instead of 6022.Research limitations/implications: Research limitation is that the width of the strip was 100 mm andinvestigation of the properties were enough for practical use. Wider strip must be cast using the twin roll caster ofthe size for production.Originality/value: The economy sheet of the 6061 for the auto mobile can be produced by the high speed twinroll caster. 6061 is typical wrought aluminum alloy of 6000 series. Therefore, the sheet of 6061 will becomeeconomy. 6061 can be recycled at two times when the 6061 is cast into strip by the high speed roll casting.

  9. Effect of metallurgical parameters on the hardness and microstructural characterization of as-cast and heat-treated 356 and 319 aluminum alloys

    International Nuclear Information System (INIS)

    The present study was undertaken to investigate the effect of metallurgical parameters on the hardness and microstructural characterization of as-cast and heat-treated 356 and 319 alloys, with the aim of adjusting these parameters to produce castings of suitable hardness and Fe-intermetallic volume fractions for subsequent use in studies relating to the machinability of these alloys. By measuring the amount of Fe- and Cu-intermetallics formed and the changes in the eutectic Si particle characteristics resulting from alloying additions (Fe, Mn, Mg), Sr-modification, and heat treatment of the 356 and 319 alloys, and the corresponding hardness values, it was possible to determine which conditions or metallurgical parameters yielded the required Fe-intermetallic volume fractions of 2 and 5% and hardness levels of 85 and 115 BHN. These levels conform to the most common levels observed in the commercial application of these alloys. The 356 and 319 alloys were examined in the as-cast and heat-treated conditions, using different combinations of grain refining, Sr-modification, and alloying additions. Aging treatments were carried out at 155, 180, 200, and 220 deg. C for 4 h, followed by air cooling, as well as at 180 and 220 deg. C for 2, 4, 6, and 8 h to determine conditions under which the specified hardness levels of 85 and 115 HBN could be obtained. Hardness measurements were carried out using a Brinell hardness tester. Peak hardness was observed in the 356 and 319 alloys at different aging conditions, depending upon the Fe-intermetallic type present in the alloy and whether the alloy was modified or not. Aging at 220 deg. C revealed a hardness peak at 2 h aging time in both 356 and 319 alloys. Addition of Mg to 319 alloys produced a remarkable increase in hardness at all aging temperatures. This may be explained on the basis of the combined effect of Cu- and Mg-intermetallics in the 319 alloys, where hardening during aging occurs by the cooperative precipitation of Al

  10. [Microbiological corrosion of aluminum alloys].

    Science.gov (United States)

    Smirnov, V F; Belov, D V; Sokolova, T N; Kuzina, O V; Kartashov, V R

    2008-01-01

    Biological corrosion of ADO quality aluminum and aluminum-based construction materials (alloys V65, D16, and D16T) was studied. Thirteen microscopic fungus species and six bacterial species proved to be able to attack aluminum and its alloys. It was found that biocorrosion of metals by microscopic fungi and bacteria was mediated by certain exometabolites. Experiments on biocorrosion of the materials by the microscopic fungus Alternaria alternata, the most active biodegrader, demonstrated that the micromycete attack started with the appearance of exudate with pH 8-9 on end faces of the samples. PMID:18669265

  11. Impact Toughness and Heat Treatment for Cast Aluminum

    Science.gov (United States)

    Lee, Jonathan A (Inventor)

    2016-01-01

    A method for transforming a cast component made of modified aluminum alloy by increasing the impact toughness coefficient using minimal heat and energy. The aluminum alloy is modified to contain 0.55%-0.60% magnesium, 0.10%-0.15% titanium or zirconium, less than 0.07% iron, a silicon-tomagnesium product ratio of 4.0, and less than 0.15% total impurities. The shortened heat treatment requires an initial heating at 1,000deg F. for up to I hour followed by a water quench and a second heating at 350deg F. to 390deg F. for up to I hour. An optional short bake paint cycle or powder coating process further increase.

  12. Effect of hot and cold deformation on the P {l_brace}0 1 1{r_brace}<4 5 5> recrystallization texture in a continuous cast Al-Mn-Mg aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.C. [Department of Chemical and Materials Engineering, University of Kentucky, 177 Anderson Hall, Lexington, KY 40506 (United States)]. E-mail: wcliu@engr.uky.edu; Morris, J.G. [Department of Chemical and Materials Engineering, University of Kentucky, 177 Anderson Hall, Lexington, KY 40506 (United States)

    2006-06-15

    The effect of different relative amounts of hot and cold deformation on the P {l_brace}0 1 1{r_brace}<4 5 5> recrystallization texture in a continuous cast Al-Mn-Mg aluminum alloy was investigated by X-ray diffraction. The results show that at a given total rolling strain the sheet with a high hot rolling strain exhibits a significantly stronger P texture than sheet with a low hot rolling strain. Hot deformation strongly promotes the formation of the P texture during recrystallization annealing.

  13. Prediction of ALLOY SHRINKAGE FACTORS FOR THE INVESTMENT CASTING PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Sabau, Adrian S [ORNL

    2006-01-01

    This study deals with the experimental measurements and numerical predictions of alloy shrinkage factors (SFs) related to the investment casting process. The dimensions of the A356 aluminum alloy casting were determined from the numerical simulation results of solidification, heat transfer, fluid dynamics, and deformation phenomena. The investment casting process was carried out using wax patterns of unfilled wax and shell molds that were made of fused silica with a zircon prime coat. The dimensions of the die tooling, wax pattern, and casting were measured, in order to determine the actual tooling allowances. Several numerical simulations were carried out, to assess the level of accuracy for the casting shrinkage. The solid fraction threshold, at which the transition from the fluid dynamics to the solid dynamics occurs, was found to be important in predicting shrinkage factors (SFs). It was found that accurate predictions were obtained for all measued dimensions when the shell mold was considered a deformable material.

  14. Die Casting Mold Design of the Thin-walled Aluminum Case by Computational Solidification Simulation

    Institute of Scientific and Technical Information of China (English)

    Young-Chan Kim; Chang-Seog Kang; Jae-Ik Cho; Chang-Yeol Jeong; Se-Weon Choi; Sung-Kil Hong

    2008-01-01

    Recently, demand for the lightweight alloy in electric/electronic housings has been greatly increased. However, among the lightweight alloys, aluminum alloy thin-walled die casting is problematic because it is quite difficult to achieve sufficient fluidity and feedability to fill the thin cavity as the wall thickness becomes less than 1 mm. Therefore, in this study, thin-walled die casting of aluminum (Al-Si-Cu alloy: ALDC 12) in size of notebook computer housing and thickness of 0.8 mm was investigated by solidification simulation (MAGMA soft) and actual casting experiment (Buhler Evolution B 53D). Three different types of gating design, finger, tangential and split type with 6 vertical runners, were simulated and the results showed that sound thin-walled die casting was possible with tangential and split type gating design because those gates allowed aluminum melt to flow into the thin cavity uniformly and split type gating system was preferable gating design comparing to tangential type gating system at the point of view of soundness of casting and distortion generated after solidification. Also, the solidification simulation agreed well with the actual die-casting and the casting showed no casting defects and distortion.

  15. Virtual aluminum castings: An industrial application of ICME

    Science.gov (United States)

    Allison, John; Li, Mei; Wolverton, C.; Su, Xuming

    2006-11-01

    The automotive product design and manufacturing community is continually besieged by Hercule an engineering, timing, and cost challenges. Nowhere is this more evident than in the development of designs and manufacturing processes for cast aluminum engine blocks and cylinder heads. Increasing engine performance requirements coupled with stringent weight and packaging constraints are pushing aluminum alloys to the limits of their capabilities. To provide high-quality blocks and heads at the lowest possible cost, manufacturing process engineers are required to find increasingly innovative ways to cast and heat treat components. Additionally, to remain competitive, products and manufacturing methods must be developed and implemented in record time. To bridge the gaps between program needs and engineering reality, the use of robust computational models in up-front analysis will take on an increasingly important role. This article describes just such a computational approach, the Virtual Aluminum Castings methodology, which was developed and implemented at Ford Motor Company and demonstrates the feasibility and benefits of integrated computational materials engineering.

  16. Low Cost Al-Si Casting Alloy As In-Situ Composite for High Temperature Applications

    Science.gov (United States)

    Lee, Jonathan A.

    2000-01-01

    A new aluminum-silicon (Al-Si) alloy has been successfully developed at NASA- Marshall Space Flight Center (MSFC) that has significant improvement in tensile and fatigue strength at elevated temperatures (500 F-700 F). The alloy offers a number of benefits such as light weight, high hardness, low thermal expansion and high surface wear resistance. In hypereutectic form, this alloy is considered as an in-situ Al-Si composite with tensile strength of about 90% higher than the auto industry 390 alloy at 600 F. This composite is very economically produced by using either conventional permanent steel molds or die casting. The projected material cost is less than $0.90 per pound, and automotive components such as pistons can be cast for high production rate using conventional casting techniques with a low and fully accounted cost. Key Words: Metal matrix composites, In-situ composite, aluminum-silicon alloy, hypereutectic alloy, permanent mold casting, die casting.

  17. Combining Aluminum Heat Treat with Hot Isostatic Pressing:A Comparison of Structure, Properties, and Processing Routes for a Cast Al-Si-Mg Alloy

    Institute of Scientific and Technical Information of China (English)

    Stephen J. Mashl

    2004-01-01

    Bodycote researchers have successfully demonstrated that a T6 heat treatment can be integrated with Densal(R), a proprietary, aluminum specific, hot isostatic pressing (HIP) process. In this combined operation, at least a portion of the solution heat treatment is conducted at elevated pressure. During development, two issues, adiabatic cooling during depressurization and a possible variation in the kinetics of homogenization resulting from conducting the solution heat treat at elevated pressure were perceived as factors which could alter the heat treat response fiom that seen in conventional processing.This paper reviews the results of experiments performed to A1-Si-Mg (A356.0) castings subjected to both combined and conventional processing routes. Results indicate that the combined HIP and heat treat process is an efficient means of achieving a microstructure characteristic of a conventionally T6 processed material while eliminating porosity within the casting. Further, the fatigue life of an A356.0 casting processed using the combined cycle can be improved by more than an order of magnitude over the as-cast and T6 treated component.

  18. Comparison of recrystallization and recrystallization textures in cold-rolled DC and CC AA 5182 aluminum alloys

    International Nuclear Information System (INIS)

    The recrystallization and recrystallization textures in cold-rolled direct chill cast (DC) and continuous cast (CC) AA 5182 aluminum alloys were investigated. The recrystallization behavior of cold-rolled DC and CC AA 5182 aluminum alloys was evaluated by tensile properties. The evolution of recrystallization textures in cold-rolled DC and CC AA 5182 aluminum alloys was determined by X-ray diffraction. The results showed that the recrystallization temperature of cold-rolled DC AA 5182 aluminum alloy was somewhat lower than that of cold-rolled CC AA 5182 aluminum alloy. The resulting recrystallization textures of cold-rolled AA 5182 aluminum alloy were characterized by the strong R orientation and the cube orientation with strong scattering about the rolling direction towards the Goss orientation. CC AA 5182 aluminum alloy showed slightly weaker recrystallization textures than DC AA 5182 aluminum alloy

  19. Advanced metrology of surface defects measurement for aluminum die casting

    Directory of Open Access Journals (Sweden)

    D. Myszka

    2011-07-01

    Full Text Available The scientific objective of the research is to develop a strategy to build computer based vision systems for inspection of surface defects inproducts, especially discontinuities which appear in castings after machining. In addition to the proposed vision inspection method theauthors demonstrates the development of the advanced computer techniques based on the methods of scanning to measure topography ofsurface defect in offline process control. This method allow to identify a mechanism responsible for the formation of casting defects. Also,the method allow investigating if the, developed vision inspection system for identification of surface defects have been correctlyimplemented for an online inspection. Finally, in order to make casting samples with gas and shrinkage porosity defects type, the LGT gas meter was used . For this task a special camera for a semi-quantitative assessment of the gas content in aluminum alloy melts, using a Straube-Pfeiffer method was used. The results demonstrate that applied solution is excellent tool in preparing for various aluminum alloysthe reference porosity samples, identified next by the computer inspection system.

  20. Gating of Permanent Molds for Aluminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-01-01

    This report summarizes a two-year project, DE-FC07-011D13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was to determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings. Equipment and procedure for real time X-Ray radiography of molten aluminum flow into permanent molds have been developed. Other studies have been conducted using water flow and behavior of liquid aluminum in sand mold using real time photography. This investigation utilizes graphite molds transparent to X-Rays making it possible to observe the flow pattern through a number of vertically oriented grating systems. These have included systems that are choked at the base of a rounded vertical sprue and vertical gating systems with a variety of different ingates into the bottom of a mold cavity. These systems have also been changed to include gating systems with vertical and horizontal gate configurations. Several conclusions can be derived from this study. A sprue-well, as designed in these experiments, does not eliminate the vena contracta. Because of the swirling at the sprue-base, the circulating metal begins to push the entering metal stream toward the open runner mitigating the intended effect of the sprue-well. Improved designs of

  1. Welding and mechanical properties of cast FAPY (Fe-16 at. % Al-based) alloy slabs

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Goodwin, G.M.; Alexander, D.J.; Howell, C.R.

    1995-08-01

    The low-aluminum-content iron-aluminum program deals with the development of a Fe-Al alloy with aluminum content such as a produce the minimum environmental effect at room temperature. The FAPY is an Fe-16 at. % Al-based alloy developed at the Oak Ridge National Laboratory as the highest aluminum-containing alloy with essentially no environmental effect. The chemical composition for FAPY in weight percent is: aluminum = 8.46, chromium = 5.50, zirconium = 0.20, carbon = 0.03, molybdenum = 2.00, yttrium = 0.10, and iron = 83.71. The cast ingots of the alloy can be hot worked by extrusion, forging, and rolling processes. The hot- worked cast structure can be cold worked with intermediate anneals at 800{degrees}C. Typical room-temperature ductility of the fine-grained wrought structure is 20 to 25% for this alloy. In contrast to the wrought structure, the cast ductility at room temperature is approximately 1% with a transition temperature of approximately 100 to 150{degrees}C, above which ductility values exceed 20%. The alloy has been melted and processed into bar, sheet, and foil. The alloy has also been cast into slabs, step-blocks of varying thicknesses, and shapes. The purpose of this section is to describe the welding response of cast slabs of three different thicknesses of FAPY alloy. Tensile, creep, and Charpy-impact data of the welded plates are also presented.

  2. A New Method for Evaluating Fatigue Property of A713 Cast Aluminum Alloy%评价铸造A713铝合金疲劳性能的新方法

    Institute of Scientific and Technical Information of China (English)

    张元彬; 罗辉; 霍玉双; 刘鹏; 翟同广

    2012-01-01

    在材料试验机上对铸造A713铝合金进行四点弯曲疲劳试验,并通过一种评价疲劳性能的新方法获得了该合金的疲劳弱点密度和强度曲线。结果表明:试验获得的铸造A713铝合金的疲劳强度为94.5MPa;该合金的疲劳弱点密度符合Weibull分布方程,疲劳弱点强度在应力水平为65%时最大;与气孔尺寸分布相比,疲劳弱点密度和强度的分布更适合作为材料疲劳性能的评价指标。%The four points bending fatigue test was applied to A713 cast aluminum alloy by a material tester,and the curves of the density and strength of fatigue weakest link of the alloy were obtained by a new method of evaluating fatigue property.The results show that the fatigue strength of A713 cast aluminum alloy obtained by this method was 94.5 MPa.The fatigue weakest link density corresponded with Weibull distribution equation,and the fatigue weakest link strength was maximum when the stress level was 65%.Compared with pore size distribution,the distribution of density and strength of fatigue weakest link was more suitable to be used as the evaluation index of fatigue property of materials.

  3. Microstructure and interface reaction of investment casting TiAl alloys

    Institute of Scientific and Technical Information of China (English)

    CHEN Yu-yong; XIAO Shu-long; KONG Fan-tao; WANG Xue

    2006-01-01

    In order to research the microstructure of TiAl alloy and TiAl-mould reaction between TiAl and ceramic mould shells prepared with the low cost binder in investment casting, the ceramic mould shells were prepared with low cost binder and refractory materials. Using two kinds of casting methods (gravity casting and centrifugal casting), the titanium aluminum alloys with rare earth element (Ti-47.5Al-2Cr-2Nb-0.3Y and Ti-45Al-5Nb-0.3Y) were cast into the mould shells. The microstructures of investment casting titanium aluminum alloys were observed by optical microscope (OM). The distributions of elements of topping investment on the surfaces of titanium aluminum alloys castings were analyzed by the means of electron probe micro-analysis (EPMA), and the mechanical properties were studied. The results show that the microstructures of two kinds of titanium aluminum alloys are both lamella shape, and lamella is thin. The thickness of reaction and diffusing layer of Ti-47.5Al-2Cr-2Nb-0.3Y alloy is about 80 μm, and that of Ti-45Al-5Nb-0.3Y is less than 30 μm.

  4. Evaluation of Cracking Causes of AlSi5Cu3 Alloy Castings

    Directory of Open Access Journals (Sweden)

    Eperješi Š.

    2014-10-01

    Full Text Available Recently, the castings made from aluminum-silicon alloys by pressure die casting are increasingly used in the automotive industry. In practice, on these castings are high demands, mainly demands on quality of their structure, operating life and safety ensuring of their utilization. The AlSi5Cu3 alloy castings are widely used for production of car components. After the prescribed tests, the cracks and low mechanical properties have been identified for several castings of this alloy, which were produced by low pressure casting into a metal mould and subsequent they were heat treated. Therefore, analyses of the castings were realized to determine the causes of these defects. Evaluation of structure of the AlSi5Cu3 alloy and causes of failure were the subjects of investigation presented in this article.

  5. Development and application of titanium alloy casting technology in China

    Institute of Scientific and Technical Information of China (English)

    NAN Hai; XIE Cheng-mu; ZHAO Jia-qi

    2005-01-01

    The development and research of titanium cast alloy and its casting technology, especially its application inaeronautical industry in China are presented. The technology of molding, melting and casting of titanium alloy, casting quality control are introduced. The existing problems and development trend in titanium alloy casting technology are also discussed.

  6. Investigating aluminum alloy reinforced by graphene nanoflakes

    Energy Technology Data Exchange (ETDEWEB)

    Yan, S.J., E-mail: shaojiuyan@126.com [Beijing Institute of Aeronautical Materials, Beijing 100095 (China); Dai, S.L.; Zhang, X.Y.; Yang, C.; Hong, Q.H.; Chen, J.Z. [Beijing Institute of Aeronautical Materials, Beijing 100095 (China); Lin, Z.M. [Aviation Industry Corporation of China, Beijing 100022 (China)

    2014-08-26

    As one of the most important engineering materials, aluminum alloys have been widely applied in many fields. However, the requirement of enhancing their mechanical properties without sacrificing the ductility is always a challenge in the development of aluminum alloys. Thanks to the excellent physical and mechanical properties, graphene nanoflakes (GNFs) have been applied as promising reinforcing elements in various engineering materials, including polymers and ceramics. However, the investigation of GNFs as reinforcement phase in metals or alloys, especially in aluminum alloys, is still very limited. In this study, the aluminum alloy reinforced by GNFs was successfully prepared via powder metallurgy approach. The GNFs were mixed with aluminum alloy powders through ball milling and followed by hot isostatic pressing. The green body was then hot extruded to obtain the final GNFs reinforced aluminum alloy nanocomposite. The scanning electron microscopy and transmission electron microscope analysis show that GNFs were well dispersed in the aluminum alloy matrix and no chemical reactions were observed at the interfaces between the GNFs and aluminum alloy matrix. The mechanical properties' testing results show that with increasing filling content of GNFs, both tensile and yield strengths were remarkably increased without losing the ductility performance. These results not only provided a pathway to achieve the goal of preparing high strength aluminum alloys with excellent ductilitybut they also shed light on the development of other metal alloys reinforced by GNFs.

  7. Investigating aluminum alloy reinforced by graphene nanoflakes

    International Nuclear Information System (INIS)

    As one of the most important engineering materials, aluminum alloys have been widely applied in many fields. However, the requirement of enhancing their mechanical properties without sacrificing the ductility is always a challenge in the development of aluminum alloys. Thanks to the excellent physical and mechanical properties, graphene nanoflakes (GNFs) have been applied as promising reinforcing elements in various engineering materials, including polymers and ceramics. However, the investigation of GNFs as reinforcement phase in metals or alloys, especially in aluminum alloys, is still very limited. In this study, the aluminum alloy reinforced by GNFs was successfully prepared via powder metallurgy approach. The GNFs were mixed with aluminum alloy powders through ball milling and followed by hot isostatic pressing. The green body was then hot extruded to obtain the final GNFs reinforced aluminum alloy nanocomposite. The scanning electron microscopy and transmission electron microscope analysis show that GNFs were well dispersed in the aluminum alloy matrix and no chemical reactions were observed at the interfaces between the GNFs and aluminum alloy matrix. The mechanical properties' testing results show that with increasing filling content of GNFs, both tensile and yield strengths were remarkably increased without losing the ductility performance. These results not only provided a pathway to achieve the goal of preparing high strength aluminum alloys with excellent ductilitybut they also shed light on the development of other metal alloys reinforced by GNFs

  8. Hydrogen effects in aluminum alloys

    International Nuclear Information System (INIS)

    The permeability of six commercial aluminum alloys to deuterium and tritium was determined by several techniques. Surface films inhibited permeation under most conditions; however, contact with lithium deuteride during the tests minimized the surface effects. Under these conditions phi/sub D2/ = 1.9 x 10-2 exp (--22,400/RT) cc (NTP)atm/sup --1/2/ s-1cm-1. The six alloys were also tested before, during, and after exposure to high pressure hydrogen, and no hydrogen-induced effects on the tensile properties were observed

  9. [Casting faults and structural studies on bonded alloys comparing centrifugal castings and vacuum pressure castings].

    Science.gov (United States)

    Fuchs, P; Küfmann, W

    1978-07-01

    The casting processes in use today such as centrifugal casting and vacuum pressure casting were compared with one another. An effort was made to answer the question whether the occurrence of shrink cavities and the mean diameter of the grain of the alloy is dependent on the method of casting. 80 crowns were made by both processes from the baked alloys Degudent Universal, Degudent N and the trial alloy 4437 of the firm Degusa. Slice sections were examined for macro and micro-porosity and the structural appearance was evaluated by linear analysis. Statistical analysis showed that casting faults and casting structure is independent of the method used and their causes must be found in the conditions of casting and the composition of the alloy. PMID:352670

  10. Solidification Conditions and Microstructure in Continuously Cast Aluminum

    Science.gov (United States)

    Buxmann, K.; Gold, E.

    1982-04-01

    The well-known relationship between cell size or dendrite spacing and local solidification time gives the possibility of calculating the thermal parameters of solidification from the microstructure of the as-cast product. As a basis for such calculations, the dendrite spacing of different aluminum castings (DC cast ingots of different diameters, cast in conventional and electromagnetic molds; cast strip from roll casters, belt casters, and block casters; and Properzi cast rod) has been measured through their cross sections. Based on these measurements, a qualitative discussion of the thermal conditions during the solidification of these products is given, and the influence of a variation in the casting conditions discussed.

  11. Investigation of microporosity in die-cast AlSi12(Cu) alloys by neutron- and X-ray radiography

    International Nuclear Information System (INIS)

    The porosity of the casting can dramatically reduce the solidity and reliability of the objects made from aluminum alloys. The X-ray radiography is able to find the placement of the porosity of the aluminum devices. After a special 'water saturation' process the dynamic neutron radiography is available to discover the 'dangerous' surface nearporosity in the aluminum samples. The X-ray and neutron radiography were used as complementary examination techniques to study the porosity of the aluminum castings.(author)

  12. Microstructure of AM50 die casting magnesium alloy

    Directory of Open Access Journals (Sweden)

    A. Kiełbus

    2006-08-01

    Full Text Available Purpose: AM50 magnesium alloy allows high-energy absorption and elongation at high strength and has goodcastability. It contains aluminum and manganese. Typically, it is used in automotive industry for steering wheels,dashboards and seat frames. The aim of this paper is to present the results of investigations on the microstructureof the AM50 magnesium alloy in an ingot condition and after hot chamber die casting.Design/methodology/approach: Die casting was carried out on 280 tone locking force hot-chamber die castingmachine. For the microstructure observation, a Olympus GX+70 metallographic microscope and a HITACHIS-3400N scanning electron microscope with a Thermo Noran EDS spectrometer equipped with SYSTEM SIXwere used.Findings: Based on the investigation carried out it was found that the AM50 magnesium alloy in as ingotcondition is characterized by a solid solution structure a with partially divorced eutectic (a + Mg17Al12 andprecipitates of Mn5Al8 phase. After hot chamber die casting is characterized by a solid solution structure awith fully divorced eutectic a + Mg17Al12. Moreover, the occurrence of Mn5Al8 phase and some shrinkageporosity has been proved.Research limitations/implications: Future researches should contain investigations of the influence of the diecasting process parameters on the microstructure and mechanical properties of AM50 magnesium.Practical implications: AM50 magnesium alloy can be cast with cold- and hot-chamber die casting machine.Results of investigation may be useful for preparing die casting technology of this alloy.Originality/value: The results of the researches make up a basis for the investigations of new magnesium alloysfor hot chamber die casting with addition of RE elements designed to exploitation in temperature to 175°C.

  13. Microbial corrosion of aluminum alloy.

    Science.gov (United States)

    Yang, S S; Chen, C Y; Wei, C B; Lin, Y T

    1996-11-01

    Several microbes were isolated from the contaminated fuel-oil in Taiwan and the microbial corrosion of aluminum alloy A356-T6 was tested by MIL-STD-810E test method. Penicillium sp. AM-F5 and Cladosporium resinac ATCC 22712 had significant adsorption and pitting on the surface of aluminum alloy, Pseudomonas acruginosa AM-B5 had weak adsorption and some precipitation in the bottom, and Candida sp. AM-Y1 had the less adsorption and few cavities formation on the surface. pH of the aqueous phase decreased 0.3 to 0.7 unit for 4 months of incubation. The corrosion of aluminum alloy was very significant in the cultures of Penicillium sp. AM-F2, Penicillium sp. AM-F5 and C. resinac ATCC 22712. The major metabolites in the aqueous phase with the inoculation of C. resinac were citric acid and oxalic acid, while succinic acid and fumaric acid were the minors. PMID:10592801

  14. Casting behavior of titanium alloys in a centrifugal casting machine.

    Science.gov (United States)

    Watanabe, K; Miyakawa, O; Takada, Y; Okuno, O; Okabe, T

    2003-05-01

    Since dental casting requires replication of complex shapes with great accuracy, this study examined how well some commercial titanium alloys and experimental titanium-copper alloys filled a mold cavity. The metals examined were three types of commercial dental titanium [commercially pure titanium (hereinafter noted as CP-Ti), Ti-6Al-4V (T64) and Ti-6Al-7Nb (T67)], and experimental titanium-copper alloys [3%, 5% and 10% Cu (mass %)]. The volume percentage filling the cavity was evaluated in castings prepared in a very thin perforated sheet pattern and cast in a centrifugal casting machine. The flow behavior of the molten metal was also examined using a so-called "tracer element technique." The amounts of CP-Ti and all the Ti-Cu alloys filling the cavity were similar; less T64 and T67 filled the cavity. However, the Ti-Cu alloys failed to reach the end of the cavities due to a lower fluidity compared to the other metals. A mold prepared with specially designed perforated sheets was effective at differentiating the flow behavior of the metals tested. The present technique also revealed that the more viscous Ti-Cu alloys with a wide freezing range failed to sequentially flow to the end of the cavity. PMID:12593955

  15. Effect of electromagnetic field on macrosegregation of continuous casting 7075 alloy

    Institute of Scientific and Technical Information of China (English)

    张北江; 崔建忠; 路贵民; 张勤; 班春燕

    2003-01-01

    The effect of electromagnetic field on macrosegregation of continuous casting aluminum alloy was stud-ied. 7075 aluminum alloy ingot with diameter of 200 mm was produced by electromagnetic casting. Magnitude of coilcurrent was varied from 100 A to 600 A, and frequency from 10 Hz to 100 Hz. Variation of element content along theradius of ingot was examined by means of chemical analysis. The results show that electromagnetic casting processcan effectively reduce the macrosegregation, and electromagnetic frequency has a great influence on element distribu-tion along the radius of ingot. When frequency is 30 Hz, macrosegregation is eliminated completely.

  16. Microstructural features of intergranular brittle fracture and cold cracking in high strength aluminum alloys

    NARCIS (Netherlands)

    Lalpoor, M.; Eskin, D. G.; ten Brink, Gert; Katgerman, L.

    2010-01-01

    Intergranular brittle fracture has been mainly observed and reported in steel alloys and precipitation hardened At-alloys where intergranular precipitates cover a major fraction of the grain boundary area. 7xxx series aluminum alloys suffer from this problem in the as-cast condition when brittle int

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

    OpenAIRE

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

    2013-01-01

    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 shrin...

  18. Casting of Titanium and its Alloys

    OpenAIRE

    R. L. Saha; K. T. Jacob

    1986-01-01

    Titaniuni and its alloys have many applications in aerospace, marine and other engineering industries. Titanium requires special melting techniques because of its high reactivity at elevated temperatures and needs special mould materials and methods for castings. This paper reviews the development of titanium casting technology.

  19. Casting of Titanium and its Alloys

    Directory of Open Access Journals (Sweden)

    R. L. Saha

    1986-04-01

    Full Text Available Titaniuni and its alloys have many applications in aerospace, marine and other engineering industries. Titanium requires special melting techniques because of its high reactivity at elevated temperatures and needs special mould materials and methods for castings. This paper reviews the development of titanium casting technology.

  20. Interfacial Heat Transfer during Die Casting of an Al-Si-Cu Alloy

    Science.gov (United States)

    Hamasaiid, A.; Wang, G.; Davidson, C.; Dour, G.; Dargusch, M. S.

    2009-12-01

    The relationship between in-cavity pressure, heat flux, and heat-transfer coefficient during high-pressure die casting of an Al-9 pct Si-3 pct Cu alloy was investigated. Detailed measurements were performed using infrared probes and thermocouple arrays that accurately determine both casting and die surface temperatures during the pressure die casting of an aluminum A380 alloy. Concurrent in-cavity pressure measurements were also performed. These measurements enabled the correlation between in-cavity pressure and accurate heat-transfer coefficients in high-pressure die-casting operations.

  1. Low-alloy constructional cast steel

    Directory of Open Access Journals (Sweden)

    D. Bartocha

    2011-07-01

    Full Text Available Production of constructional casting competitive for welded structure of high-strength steel first of all required high metallurgical quality of cast steel. Assumptions, methodology and results of investigation which the aim was determination of the most advantageous: configuration and parameters of metallurgical treatments and ways to modify, in aspects of reach the low-alloy cast steel of the highest quality as possible, are presented. A series of low-alloy cast steel melts modeled on cast steel L20HGSNM was performed, the way of argoning in laboratory induction furnace with a capacity of 50kg was worked out, modifications with additions of FeNb, FeV and master alloy MgCe were performed. During each melts samples of cast steel direct from metal bath were get and series of experimental casting was made. Chemical compositions of melted cast steel, contents of O, N and H were determined as well as influence of additions on structure and nature of impact strength samples fracture were estimated.

  2. Aluminium Alloy Cast Shell Development for Torpedoes

    Directory of Open Access Journals (Sweden)

    Vijaya Singh

    2005-01-01

    Full Text Available The sand-cast aluminium alloy cylindrical shells were developed for the advanced experimental torpedo applications. The components had intricate geometry, thin-walled sections, and stringent property requirements. The casting defects, such as shrinkage, porosity, incomplete filling of thin sections, cold shuts, inclusions and dimensional eccentricity, etc were found inthe initial castings trials. improvements in casting quality were achieved through modified methodology, selective chilling, risering, and by introducing ceramic-foam filters in the gatingsystem. The heat-treated and machined components met radiographic class I grade C/E standards, mechanical properties to BS1490 specifications, and leakage and hydraulic pressure testrequirements relevant for such applications.

  3. Alloying and Casting Furnace for Shape Memory Alloys Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The concept in the proposed project is to create a melting, alloying and casting furnace for the processing titanium based SMA using cold crucible techniques. The...

  4. ''Heat Transfer at the Mold-Metal Interface in Permanent Mold Casting of Aluminum Alloys'' Final Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Professor R. D. Pehlke, Principal Investigator, Dr. John M. Cookson, Dr. Shouwei Hao, Dr. Prasad Krishna, Kevin T. Bilkey

    2001-12-14

    This project on heat transfer coefficients in metal permanent mold casting has been conducted in three areas. They are the theoretical study at the University of Michigan, the experimental investigation of squeeze casting at CMI-Tech Center (Now Hayes-Lemmerz Technical Center) and the experimental investigation of low pressure permanent mold casting at Amcast Automotive.

  5. Structure analysis of Al cast alloy

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2008-03-01

    Full Text Available Purpose: The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all - to reduce the amount of the waste products.Design/methodology/approach: Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the “Cosworth” technological process. In this work the AC-AlSi7Cu3Mg alloy structure was investigated, of this alloy samples were cut of for structure analysis of the cylinder part as well of crankshaft of a fuel engine. The investigation show a difference in the (phase structure morphology as a result of cast cooling rate.Findings: On the quality of casting has influence the walls thickness of car engine elements’.Practical implications: In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters.Originality/value: The value of the applied methodology was to correct identify the casting effects that occurred during the casting process.

  6. Laser surface treatment of cast magnesium alloys

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2009-02-01

    Full Text Available Purpose: The goal of this work was to investigate influence of laser treatment on structure and properties MCMgAl3Zn1, MCMgAl6Zn1, MCMgAl9Zn1 and MCMgAl12Zn1 cast magnesium alloys.Design/methodology/approach: Tests were made on the experimental MCMgAl3Zn1 MCMgAl6Zn1 MCMgAl9Zn1 and MCMgAl12Zn1 casting magnesium alloys. Laser treatment was made using the Rofin DL020 HPDL high power diode laser in the argon shield gas cover with the technique of the continuous powder supply to the remelted pool area.Findings: Investigations of the surface layers carried out confirm that laser treatment of the surface layer of the Mg-Al-Zn casting magnesium alloys is feasible using the HPDL high power diode laser ensuring better properties compared to alloys properties after the regular heat treatment after employing the relevant process parameters. Occurrences were found based on the metallographic examinations of the remelted zone (RZ and the heat affected zone (HAZ in alloyed surface layer of the investigated casting magnesium alloy.Research limitations/implications: This investigation presents different laser power and in this research was used two powders, namely tungsten-, and titanium carbide.Practical implications: Reinforcing the surface of cast magnesium alloys by adding TiC and WC particles is such a possible way to achieve the possibilities of the laser melt injection process, which is a potential technique to produce a Metal-Matrix Composite (MMC layer in the top layer of a metal workpiece.Originality/value: The originality of this work is applying of High Power Diode Laser for alloying of magnesium alloy using hard particles like tungsten- and titanium carbide.

  7. Analysis and Preventive Measures of Causes of Cracks of 5A06 Aluminum Alloy Casting Ingot%5A06 铝合金铸锭裂纹原因分析及预防措施

    Institute of Scientific and Technical Information of China (English)

    高新宇; 王海彬; 孙婧彧; 谭树栋

    2015-01-01

    The reasons of 5A06 aluminum alloy casting ingot crack were analyzed through optical mi-croscope, SEM and EA.Through analyses of the casting crack, cracks are intergranular fracture that is belonging to hot cracking, and many micro -cracks were found in the crack region, and these cracks is associated with second phase.The large intragranular dispersion gathered near the cracks. The cracks were found in the end of the ingot solidification.The causes of crack of the 5A06 were an-alyzed based on formation mechanism, and the solutions are proposed in the respect of casting process.%通过显微组织、扫描电镜观察及能谱分析等手段,分析了5 A06铝合金铸锭裂纹的产生原因. 通过组织分析,该裂纹为沿晶断裂,属于热裂纹,在主裂纹区域发现很多微裂纹,并且裂纹与第二相伴生,存在大量晶内弥散相聚集于裂纹附近,裂纹发生时间为铸锭凝固末端. 并从形成机理上对5A06铝合金铸锭裂纹的成因进行了分析,从铸造工艺等方面提出了解决措施.

  8. Rheo-diecasting Process for Semi-solid Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel one-step semisolid processing technique, the rheo-diecasting (RDC) process, was developed, which adapts in situ creation of semisolid metal slurry with fine and spherical solid particles followed by direct shaping of the slurry into a near-net shape component using the existing cold chamber diecasting process. The RDC process was applied to process A356 and A380 aluminum alloys. The resulting microstructures and mechanical properties of RDC products under as-cast and various heat treatment conditions were analyzed. The experimental results show that the RDC samples have an extremely low porosity, a fine and uniform microstructure throughout entire casting, and consequently much improved strength and ductility in the as-cast condition. The strength of RDC A356 alloy can be substantially improved under T5 and T6 heat treatments without loss of ductility.

  9. Fabrication of a Zinc Aluminum Oxide Nanowire Array Photoelectrode for a Solar Cell Using a High Vacuum Die Casting Technique

    OpenAIRE

    Chin-Guo Kuo; Jung-Hsuan Chen; Yueh-Han Liu

    2014-01-01

    Zinc aluminum alloy nanowire was fabricated by the vacuum die casting. Zinc aluminum alloy was melted, injected into nanomold under a hydraulic pressure, and solidified as nanowire shape. Nanomold was prepared by etching aluminum sheet with a purity of 99.7 wt.% in oxalic acid solution. A nanochannel within nanomold had a pore diameter of 80 nm and a thickness of 40 μm. Microstructure and characteristic analysis of the alumina nanomold and zinc-aluminum nanowire were performed by scanning ele...

  10. 大型复杂铝合金汽车动力部件的压铸技术开发%Development of Aluminum Alloy Large Complicated Vehicle Power Parts by Die Casting

    Institute of Scientific and Technical Information of China (English)

    张百在; 陈亮; 万里; 黄志垣; 涂云松; 常移迁; 徐飞跃; 黄明军; 张孝水; 廖伟平

    2009-01-01

    Aiming at a die casting large complicated aluminum alloy power parts, some technological ways including improving flow types and optimizing vacuum exhausting structure are employed to significantly reduce the gas-entrapment defects in the parts on the basis of understanding flow and filling process of liquid aluminum alloy by numerical simulation and physical examination. Meanwhile, shrinkage porosity (hole) in the parts is eliminated by adopting movable insert, local pressurization and exact control for die temperature. Through above technological ways, both the appearance and quality of the parts can meet the designing requirements, realizing volumetric-production in a short time.%针对某大型复杂铝合金动力部件的压铸成形,应用数值模拟和物理模拟方法,在准确把握铝合金液体流动充型状态的基础上,提出了改善铝液流动形态,优化真空排气结构的技术措施,大大减少了铸件内部的卷气缺陷.同时还采用活块、局部加压、模温精确控制等技术手段消除了内部缩孔/缩松缺陷,使铸件外观及内部品质均达到了设计要求,在短期内即实现了批量生产.

  11. Spatial Bimetallic Castings Manufactured from Iron Alloys

    Directory of Open Access Journals (Sweden)

    M. Cholewa

    2007-07-01

    Full Text Available In this paper a conception for manufacturing method of skeleton castings with composite features was shown. Main application of such castings are the working organs of machines subjected to intensive abrasive and erosive wear. Skeleton geometry was based on three-dimensional cubic net consisting of circular connectors and nodes joining 6 connectors according to Cartesian co-ordinate system. Dimension of an elementary cell was equal to 10 mm and diameter of single connector was equal to 5 mm. For bimetallic castings preparation two Fe based alloys were used: L25SHMN cast steel for skeleton substrate and ZlCr15NiMo cast iron for working part of the casting. In presented work obtained structure was analyzed with indication of characteristic regions. Authors described phenomena occurring at the alloys interface and phases in transition zone. A thesis was formulated concerning localization of transition zone at the cast iron matrix – cast steel reinforcement interface. Direction of further studies were indicated.

  12. Advanced powder metallurgy aluminum alloys and composites

    Science.gov (United States)

    Lisagor, W. B.; Stein, B. A.

    1982-01-01

    The differences between powder and ingot metallurgy processing of aluminum alloys are outlined. The potential payoff in the use of advanced powder metallurgy (PM) aluminum alloys in future transport aircraft is indicated. The national program to bring this technology to commercial fruition and the NASA Langley Research Center role in this program are briefly outlined. Some initial results of research in 2000-series PM alloys and composites that highlight the property improvements possible are given.

  13. Materials data handbook, aluminum alloy 6061

    Science.gov (United States)

    Sessler, J.; Weiss, V.

    1969-01-01

    Comprehensive compilation of technical data on aluminum alloy 6061 is presented in handbook form. The text includes data on the properties of the alloy at cryogenic, ambient, and elevated temperatures and other pertinent information required for the design and fabrication of components and equipment utilizing this alloy.

  14. Roll casting of 5182 aluminium alloy

    OpenAIRE

    Haga, T; M. Mtsuo; D. Kunigo; Hatanaka, Y; R. Nakamuta; H. Watari; S. Kumai

    2009-01-01

    Purpose: of this paper is investigation of the ability of the high speed roll casting of 5182 aluminium alloy. Appropriate twin roll caster to cast the 5182 strip was researched.Design/methodology/approach: Method used in the present study was an unequal diameter twin roll caster and a vertical type high speed twin roll caster equipped with mild steel rolls without parting material.Findings: are that the vertical type high speed twin roll caster was effective to cast 5182 strip at high speed....

  15. Numerical determination of heat distribution and castability simulations of as cast Mg-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Shehzad Saleem; Hort, Norbert [Institute for Materials Research, GKSS Forschungszentrum GmbH, Geesthacht (Germany); Eiken, Janin; Steinbach, Ingo [RWTH Aachen, ACCESS e.V., Aachen (Germany); Schmauder, Siegfried [Institut fuer Materialpruefung, Werkstoffkunde und Festigkeitslehre (IMWF), University Stuttgart (Germany)

    2009-03-15

    Magnesium alloys offer a large potential as lightweight structures especially in the automotive industry. Research and development of magnesium alloys depend largely on the metallurgist's understanding and ability to control the microstructure of the as cast part. This research work comprises the determination of experimental parameters to simulate fluidity and microstructure of magnesium/aluminum binary alloys. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  16. Evaluation and Characterization of In-Line Annealed Continuous Cast Aluminum Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Dr Subodh K. Das

    2006-01-17

    This R&D program will develop optimized, energy-efficient thermo-mechanical processing procedures for in-line annealing of continuously cast hot bands of two 5000 series aluminum alloys (5754 and 5052). The implementation of the R&D will result in the production of sheet with improved formability at high levels of productivity consistency and quality. The proposed R&D involves the following efforts: (1) Design and build continuous in-line annealing equipment for plant-scale trials; (2) Carry out plant-scale trials at Commonwealth Aluminum Corp.'s (CAC) plant in Carson; (3) Optimize the processing variables utilizing a metallurgical model for the kinetics of microstructure and texture evolution during thermo-mechanical processing; (4) Determine the effects of processing variables on the microstructure, texture, mechanical properties, and formability of aluminum sheet; (5) Develop design parameters for commercial implementation; and (6) Conduct techno-economic studies of the recommended process equipment to identify impacts on production costs. The research and development is appropriate for the domestic industry as it will result in improved aluminum processing capabilities and thus lead to greater application of aluminum in various industries including the automotive market. A teaming approach is critical to the success of this effort as no single company alone possesses the breadth of technical and financial resources for successfully carrying out the effort. This program will enable more energy efficient aluminum sheet production technology, produce consistent high quality product, and have The proposal addresses the needs of the aluminum industry as stated in the aluminum industry roadmap by developing new and improved aluminum processes utilizing energy efficient techniques. The effort is primarily related to the subsection on Rolling and Extrusion with the R&D to address energy and environmental efficiencies in aluminum manufacturing and will provide

  17. Mechanical properties of magnesium casting alloys

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2007-10-01

    Full Text Available Purpose: In the following paper there have been the properties of the MCMgAl12Zn1, MCMgAl9Zn1, MCMgAl6Zn1, MCMgAl3Zn1 magnesium cast alloy as-cast state and after a heat treatment presented.Design/methodology/approach: A casting cycle of alloys has been carried out in an induction crucible furnace using a protective salt bath Flux 12 equipped with two ceramic filters at the melting temperature of 750±10ºC, suitable for the manufactured material. The following results concern sliding friction, mechanical properties, scanning microscopy.Findings: The different heat treatment kinds employed contributed to the improvement of mechanical properties of the alloy with the slight reduction of its plastic properties.Research limitations/implications: According to the alloys characteristic, the applied cooling rate and alloy additions seems to be a good compromise for mechanical properties and microstructures, nevertheless further tests should be carried out in order to examine different cooling rates and parameters of solution treatment process and aging process.Practical implications: The concrete examples of the employment of castings from magnesium alloys in the automotive industry are elements of the suspension of the front and rear axes of cars, propeller shaft tunnel, pedals, dashboards, elements of seats, steering wheels, elements of timer-distributors, air filters, wheel bands, oil sumps, elements and housings of the gearbox, framing of doors and sunroofs, and others, etc.Originality/value: Contemporary materials should possess high mechanical properties, physical and chemical, as well as technological ones, to ensure long and reliable use. The above mentioned requirements and expectations regarding the contemporary materials are met by the non-ferrous metals alloys used nowadays, including the magnesium alloys.

  18. Analysis of influence of chemical composition of Al-Si-Cu casting alloy on formation of casting defects

    Directory of Open Access Journals (Sweden)

    R. Maniara

    2007-04-01

    Full Text Available Purpose: A methodology of the computer-aided determining relationship between chemical composition of aluminum alloy and castings quality was presented in the paper.Design/methodology/approach: To resolve the problem artificial neural networks were used. Classification problems were evaluated by the consideration mainly the values of mistakes and correct answers of networks for test data. On the basis of data analyzed by the neural network, which has the best quality classification of chemical composition of tested material, the concentration of alloying elements range, which have an effect on formation casting defects, were developed to eliminate them in the future.Findings: Combining of all methods making use of chemical composition of aluminium alloy and neural networks will make it possible to achieve a better casting quality.Research limitations/implications: The presented issues may be use, among others, for manufacturers of car subassemblies from light alloys, where meeting the stringent quality requirements ensures the demanded service life of the manufactured products.Originality/value: The correctly specified number of chemical composition of aluminum alloy enables such technological process control where the number of castings defects can be reduced by means of the proper correction of the process.

  19. Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Elevated Temperature Aluminum Metal Matrix Composite (MMC) Alloy and Its Processing Technology

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, David C. [Eck Industreis, Inc.; Gegal, Gerald A.

    2014-04-15

    The objective of this project was to provide a production capable cast aluminum metal matrix composite (MMC) alloy with an operating temperature capability of 250-300°C. Important industrial sectors as well as the military now seek lightweight aluminum alloy castings that can operate in temperature ranges of 250-300°C. Current needs in this temperature range are being satisfied by the use of titanium alloy castings. These have the desired strength properties but the end components are heavier and significantly more costly. Also, the energy requirements for production of titanium alloy castings are significantly higher than those required for production of aluminum alloys and aluminum alloy castings.

  20. Development of cast ferrous alloys for Stirling engine application

    International Nuclear Information System (INIS)

    Low cost cast ferrous base alloys that can be used for cylinder and regenerator housing components of the Stirling engine were investigated. The alloys must meet the requirements of high strength and thermal fatigue resistance to approximately 1500 F, compatibility and low permeability with hydrogen, good elevated temperature oxidation/corrosion resistance, and contain a minimum of strategic elements. The phase constituents of over twenty alloy iterations were examined by X-ray diffraction. These alloy candidates were further screened for their tensile and stress rupture strength and surface stability in air at 1450 and 1600 F, respectively. Two alloys, NASAUT 1G (Fe-10Mn-20Cr-1.5C-1.0Si) and NASAUT 4G (Fe-15Mn-12Cr-3Mo-1.5C-1.0Si-1.0Nb), were chosen for more extensive elevated temperature testing. These alloys were found to exhibit nearly equivalent elevated temperature creep strength and oxidation resistance. Silicon present in these alloys at the 1 w/o level permitted the achievement of oxide scale adherence to 1600 F without loss of strength (or ductility) as was noted for equivalent additions of aluminum

  1. Microstructural and superplastic characteristics of friction stir processed aluminum alloys

    Science.gov (United States)

    Charit, Indrajit

    Friction stir processing (FSP) is an adapted version of friction stir welding (FSW), which was invented at The Welding Institute (TWI), 1991. It is a promising solid state processing tool for microstructural modification at localized scale. Dynamic recrystallization occurs during FSP resulting in fine grained microstructure. The main goal of this research was to establish microstructure/superplasticity relationships in FSP aluminum alloys. Different aluminum alloys (5083 Al, 2024 Al, and Al-8.9Zn-2.6Mg-0.09Sc) were friction stir processed for investigating the effect of alloy chemistry on resulting superplasticity. Tool rotation rate and traverse speeds were controlled as the prime FSP parameters to produce different microstructures. In another study, lap joints of 7475 Al plates were also studied to explore the possibility of developing FSW/superplastic forming route. Microstructures were evaluated using optical, scanning and transmission electron microscopy, orientation imaging microscopy and differential scanning calorimetry. Mechanical properties were evaluated using tensile testing. FSP 2024 Al (3.9 mum grain size) exhibited an optimum ductility of 525% at a strain rate of 10-2 s-1 and 430°C. Grain boundary sliding mechanism was found to be the dominant mode of deformation in this alloy. In 5083 Al alloy, it was found that changing the process parameters, grain sizes in the range of 3.5--8.5 mum grain size could be obtained. Material processed with colder processing parameters showed a decrease in ductility due to microstructural instability, and followed solute drag dislocation glide mechanism. On the other hand, materials processed with hotter parameter combinations showed mode of deformation related to grain boundary sliding mechanism. FSP of as-cast Al-Zn-Mg-Sc alloy resulted in ultrafine grains (0.68 mum) with attractive combination of high strain rate and low temperature superplasticity. This also demonstrated that superplastic microstructures could be

  2. Materials data handbook: Aluminum alloy 2219

    Science.gov (United States)

    Muraca, R. F.; Whittick, J. S.

    1972-01-01

    A summary of the materials property information for aluminum 2219 alloy is presented. The scope of the information includes physical and mechanical properties at cryogenic, ambient, and elevated temperatures. Information on material procurement, metallurgy of the alloy, corrosion, environmental effects, fabrication, and joining techniques is developed.

  3. Friction Stir Welding of Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    FU Zhi-hong; HE Di-qiu; WANG Hong

    2004-01-01

    Friction stir welding(FSW), a new solid-state welding technology invited in the early 1990s,enables us weld aluminum alloys and titanium alloys etc. The processing of FSW, the microstructure in FSW alloysand the factors influencing weld quality are introduced. The complex factors affecting the properties are researched.

  4. Fast LIBS Identification of Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Tawfik W.

    2007-04-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to analysis aluminum alloy targets. The plasma is generated by focusing a 300 mJ pulsed Nd: YAG laser on the target in air at atmospheric pressure. Such plasma emission spectrum was collected using a one-meter length wide band fused-silica optical fiber connected to a portable Echelle spectrometer with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, electron density and electron temperature assuming the LTE and optically thin plasma conditions. The LIBS spectrum was optimized for high S/N ratio especially for trace elements. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of selected aluminum spectral lines. The values of these parameters were found to change with the aluminum alloy matrix, i.e. they could be used as a fingerprint character to distinguish between different aluminum alloy matrices using only one major element (aluminum without needing to analysis the rest of elements in the matrix. Moreover, It was found that the values of T e and N e decrease with increasing the trace elements concentrations in the aluminum alloy samples. The obtained results indicate that it is possible to improve the exploitation of LIBS in the remote on-line industrial monitoring application, by following up only the values of T e and N e for aluminum in aluminum alloys as a marker for the correct alloying using an optical fiber probe.

  5. New Approaches to Aluminum Integral Foam Production with Casting Methods

    Directory of Open Access Journals (Sweden)

    Ahmet Güner

    2015-08-01

    Full Text Available Integral foam has been used in the production of polymer materials for a long time. Metal integral foam casting systems are obtained by transferring and adapting polymer injection technology. Metal integral foam produced by casting has a solid skin at the surface and a foam core. Producing near-net shape reduces production expenses. Insurance companies nowadays want the automotive industry to use metallic foam parts because of their higher impact energy absorption properties. In this paper, manufacturing processes of aluminum integral foam with casting methods will be discussed.

  6. Interface properties and phase formation between surface coated SKD61 and aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    Se-Weon CHOI; Young-Chan KIM; Se-Hun CHANG; Ik-Hyun OH; Joon-Sik PARK; Chang-Seog KANG

    2009-01-01

    The intermediate phase formation and surface protection effects between SKD61 die mold alloys and aluminum alloys were investigated during a simulated die-casting process. The surface coatings of SKD61 alloy were carried out via Si pack cementation coatings at 900 ℃ for 10 h and the e-FeSi phase formed. When the coated SKD61 alloy was dipped in the liquid aluminum alloy (ALDC12), the surface coated SKD61 alloys showed better surface properties compared with uncoated SKD61 alloys, i.e., the intermediate phases (FeSiAl compound) were not produced for the coated SKD61 alloy. The coating layer of e-FeSi served as a diffusion barrier for the formation of FeSiAl compounds.

  7. Fast LIBS Identification of Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Tawfik W.

    2007-04-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to analysis aluminum alloy targets. The plasma is generated by focusing a 300 mJ pulsed Nd: YAG laser on the target in air at atmospheric pressure. Such plasma emission spectrum was collected using a one-meter length wide band fused-silica optical fiber connected to a portable Echelle spectrometer with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, electron density and electron temperature assuming the LTE and optically thin plasma conditions. The LIBS spectrum was optimized for high S/N ratio especially for trace elements. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of selected aluminum spectral lines. The values of these parameters were found to change with the aluminum alloy matrix, i.e. they could be used as a fingerprint character to distinguish between different aluminum alloy matrices using only one major element (aluminum without needing to analysis the rest of elements in the matrix. Moreover, It was found that the values of T(e and N(e decrease with increasing the trace elements concentrations in the aluminum alloy samples. The obtained results indicate that it is possible to improve the exploitation of LIBS in the remote on-line industrial monitoring application, by following up only the values of T(e and N(e for the aluminum in aluminum alloys using an optical fiber probe.

  8. Preferential dissolution behaviour in Ni–Cr dental cast alloy

    Indian Academy of Sciences (India)

    Viswanathan S Saji; Han Cheol Choe

    2010-08-01

    A Ni–Cr–Mo dental alloy was fabricated by three different casting methods, viz. centrifugal casting, high frequency induction casting and vacuum pressure casting. The dependence of cast microstructure on the electrochemical corrosion behaviour was investigated using potentiodynamic cyclic and potentiostatic polarization techniques, impedance spectroscopy and scanning electron microscopy. The experimental results were compared and discussed with those obtained for a Co–Cr–Mo counterpart. The results of the study showed that the variation in casting morphologies with casting methods has only marginal influence in the overall corrosion resistance of Ni–Cr and Co–Cr dental alloys. There was severe preferential dissolution of Ni rich, Cr and Mo depleted zones from the Ni–Cr–Mo alloy. The overall corrosion resistance property of the Co–Cr base alloy was better than that of the Ni–Cr base alloy.

  9. Effect of Cold Rolling on the Recrystallization Texture of Continuous Cast AA 5005 Aluminum Alloy%冷轧变形对连铸连轧5005铝合金再结晶织构的影响

    Institute of Scientific and Technical Information of China (English)

    李敬; 孙秀伟; 刘文昌

    2012-01-01

    采用X射线衍射仪研究了冷轧变形对连铸连轧5005铝合金再结晶织构的影响。结果表明:5005铝合金热轧带材具有强的B纤维轧制织构,随着冷轧变形量的增加,口纤维轧制织构的强度增大。经399℃保温3h再结晶退火处理后,5005铝合金热轧带材获得强的cube织构和弱的R织构,随着变形量的增加,cube织构强度降低,而R织构强度增加,当冷轧变形量达到93.1%时,再结晶织构由强的R织构组分及弱的cube和P织构组分构成。%The effect of cold rolling on the recrystallization texture of the hot band of continuous cast AA 5005 aluminum alloy is investigated by X-ray diffraction. The results show that the hot band possesses a strong fiber rolling texture. The strength of the fiber rolling texture increases with increasing roiling reduction. After annealing at 3990C for 3h, the recrystallization texture of AA 5005 hot band is characterized by a major cube component and a minor R component. The in- tensity of the cube orientation decreases with increasing rolling reduction,whereas the intensity of the R orientation increases. When the reduction reaches 93.1% ,the recrystallization texture con- sists of strong R component and weak cube and P components.

  10. CFD modelling of DC casting of aluminium alloys

    International Nuclear Information System (INIS)

    casting of an Al-4.5 wt% Cu alloy. The occurrence of oxides in the form of films and inclusions can give major problems during aluminum casting and processing. Inclusions and films move together with the main flow in the metal distribution system and can cause problems when trapped in the solidifying aluminum. The level of oxides and inclusions in standard DC casting practices is controlled with the use of in-line filter boxes and degassing units. However, during the transfer from these metal treatment systems to the casting station pick up of inclusions and oxides can occur. In our simulations we try to assess quantitatively some of the upstream fluid flow effects in relation to the filling behavior of the DC mould cavity and the number of inclusions trapped in the launder system. Placing baffles in the launder therefore modifies the fluid flow. The location of these baffles is an important parameter in modifying the fluid flow behavior. Both the controlled filling of the mould as well as entrapment of inclusions can be achieved. Results of numerical simulations of fluid flow with discrete particles of different mass and distribution are given. The results show that relatively subtle changes in the flow control can change the flow of inclusions drastically. Refs. 2 (author)

  11. Effect of Substrate Movement Speed by Synchronous Rolling-casting Freeform Manufacturing for Metal on Microstructure and Mechanical Property of ZLl04 Aluminum Alloy Slurry

    Institute of Scientific and Technical Information of China (English)

    LUO Xiaoqiang; LI Zhengyang; CHEN Guangnan; XU Wanli; YAN Qingzhi

    2015-01-01

    Synchronous rolling-casting freeform manufacturing for Metal (SRCFMM) means that the refined liquid metal is continuously pressed out from the bottom of crucible. There is a horizontal movable plate beneath the outlet. The clearance between the outlet and the plate is about several hundred micrometers. SRCFMM, similar to additive manufacturing, implies layer by layer shaping and consolidation of feedstock to arbitrary conifgurations, normally using a computer controlled movable plate. The primary dendritic crystal is easily crushed by movement of substrate in the rolling-casting area. ZL104 was used as the test materials, determi-ning the control temperature by differential scanning thermal analysis (DSC), preparing a kind of samples by SR CFMM, then analyzing microstructures and mechanical property of the samples. Characteristics and distribution of the primary particles were assessed by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrum (EDS) and image analysis software. Mechanical property of the samples was assessed by vickers hardness. The results show that the samples fabricated by SRCFMM have uniform structures and good performances with the velocity of the substrate controlled about 10 cm/s and temperature at about 580℃.

  12. Heat transfer at the mold-metal interface in permanent mold casting of aluminum alloys project. Quarterly project status report, January 1, 1998--March 31, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Pehlke, R.D.; Hao, Shouwei; Cookson, J.M.

    1998-03-31

    There have been numerous developments in the current project over the last three months. The most appropriate geometries for performing the interfacial heat transfer studies have been discussed with both of our Industrial Partners. Both companies have molds which may be available for adaptation to record the thermal history during casting required for determining interfacial heat transfer coefficients. The details of what instrumentation would be the most appropriate remain to be worked out, but the instrumentation would likely include thermocoupling in the mold cavity as well as in the mold wall, as well as pressure sensors in the squeeze casting geometry molds and ultrasonic gap monitoring in the low pressure and gravity fed permanent mold geometry molds. The first advisory committee meeting was held on February 6th, and the steering committee was apprised of the objectives of the program. The capabilities of the Industrial Partners were reviewed, as well as the need for the project to make use of resources from other CMC projects. The second full Advisory Committee Meeting will be held in early May.

  13. Evaluation of porosity in Al alloy die castings

    Directory of Open Access Journals (Sweden)

    M. Říhová

    2012-01-01

    Full Text Available Mechanical properties of an Al-alloy die casting depend significantly on its structural properties. Porosity in Al-alloy castings is one of the most frequent causes of waste castings. Gas pores are responsible for impaired mechanical-technological properties of cast materials. On the basis of a complex evaluation of experiments conducted on AlSi9Cu3 alloy samples taken from the upper engine block which was die- cast with and without local squeeze casting it can be said that castings manufactured without squeeze casting exhibit maximum porosity in the longitudinal section. The area without local squeeze casting exhibits a certain reduction in mechanical properties and porosity increased to as much as 5%. However, this still meets the norms set by SKODA AUTO a.s.

  14. Microstructural refinement of hyper-eutectic Al?Si?Fe?Mn cast alloys to produce a recyclable wrought material

    OpenAIRE

    Umezawa, Osamu; Nakamoto, Munefumi; Osawa, Yoshiaki; Suzuki, Kenta; Kumai, Shinji

    2005-01-01

    Although the cascade of material flow is presently suitable for the aluminum recycling, a better utilization of secondary alloys is required. In order to establish an upgradeable recycling design for developing wrought products from secondary aluminum alloys, a fine distribution of the primary phases in hyper-eutectic Al?Si?Fe?Mn cast materials has been achieved. Two novel processes were adopted. One was repeated thermomechanical treatment (RTMT), which involves a repetition of a multi-step c...

  15. Filtration of aluminum alloys and its influence on mechanical properties and shape of eutectical silicium

    Directory of Open Access Journals (Sweden)

    M. Brůna

    2008-07-01

    Full Text Available Filtration during casting of high quality aluminum alloys belongs to main refining methods. Even when there are many years of experiences and experimental works on this subject, there are still some specific anomalies. While using ceramic filtration media during casting of aluminum alloys, almost in all experiments occurred increase of strength limit and atypical increase of extension. This anomaly was not explained with classical metallurgical methods, black-white contrast after surface etching neither with color surface etching. For that reason was used deep etching on REM. By using pressed ceramic filters, by studying morphology eutectical silicon was observed modification morphology of eutectical silicon, this explains increase extension after filtration. Pressed ceramic filters were used on experimental works. Casting was executed on hardenable alloy AlSi10MgMn.

  16. Susceptibility of Aluminum Alloys to Corrosion in Simulated Fuel Blends Containing Ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, Jeffery K [ORNL; Pawel, Steven J [ORNL; Wilson, Dane F [ORNL

    2013-01-01

    The compatibility of aluminum and aluminum alloys with synthetic fuel blends comprised of ethanol and reference fuel C (a 50/50 mix of toluene and iso-octane) was examined as a function of water content and temperature. Commercially pure wrought aluminum and several cast aluminum alloys were observed to be similarly susceptible to substantial corrosion in dry (< 50 ppm water) ethanol. Corrosion rates of all the aluminum materials examined was accelerated by increased temperature and ethanol content in the fuel mixture, but inhibited by increased water content. Pretreatments designed to stabilize passive films on aluminum increased the incubation time for onset of corrosion, suggesting film stability is a significant factor in the mechanism of corrosion.

  17. Size Effect on Magnesium Alloy Castings

    Science.gov (United States)

    Li, Zhenming; Wang, Qigui; Luo, Alan A.; Zhang, Peng; Peng, Liming

    2016-06-01

    The effect of grain size on tensile and fatigue properties has been investigated in cast Mg alloys of Mg-2.98Nd-0.19Zn (1530 μm) and Mg-2.99Nd-0.2Zn-0.51Zr (41 μm). The difference between RB and push-pull fatigue testing was also evaluated in both alloys. The NZ30K05-T6 alloy shows much better tensile strengths (increased by 246 pct in YS and 159 pct in UTS) and fatigue strength (improved by ~80 pct) in comparison with NZ30-T6 alloy. RB fatigue testing results in higher fatigue strength compared with push-pull fatigue testing, mainly due to the stress/strain gradient in the RB specimen cross section. The material with coarse grains could be hardened more in the cyclic loading condition than in the monotonic loading condition, corresponding to the lower σ f and the higher σ f/ σ b or σ f/ σ 0.2 ratio compared to the materials with fine grains. The fatigue crack initiation sites and failure mechanism are mainly determined by the applied stress/strain amplitude. In LCF, fatigue failure mainly originates from the PSBs within the surface or subsurface grains of the samples. In HCF, cyclic deformation and damage irreversibly caused by environment-assisted cyclic slip is the crucial factor to influence the fatigue crack. The Coffin-Manson law and Basquin equation, and the developed MSF models and fatigue strength models can be used to predict fatigue lives and fatigue strengths of cast magnesium alloys.

  18. The effect of cast Al-Si-Cu alloy solidification rate on alloy thermal characteristics

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2006-04-01

    Full Text Available Purpose: In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters. Thus, a thermal analysis cooling curve of the alloy is used for process control in the aluminum casting industry. In this work effect of cooling rate on the size of the grains, SDAS, size of the β precipitation and thermal characteristic results of AC AlSi9Cu cast alloy have been described. The solidification process was studied using the cooling curve and crystallization curve at solidification rate ranging from 0,16 ºCs-1 up to 1,04 ºCs-1Design/methodology/approach: The experimental alloy used in this investigation was prepared by mixing the ACAlSi5Cu commercial alloys and two master alloys AlSi49 and AlCu55. Thermal analysis tests were conducted using the UMSA Technology Platform. Cooling curve thermal analysis was performed on all samples using high sensitivity thermocouples of K type. Data were acquired by a high speed data acquisition system linked to a PC computer. Each chilled sample was sectioned horizontally where the tip of the thermocouple was located and it was prepared by standard grinding and polishing procedures. Optical microscopy was used to characterize the microstructure and intermetallic phases. Secondary Dendrite Arm Spacing measurements were carried out using an Leica Q-WinTM image analyzer.Findings: Increasing the cooling rate increases significantly the liquidus temperature, nucleation undercooling temperature, solidification range and decreases the recalescence undercooling temperature. Increasing cooling rate refines all microstructural features.Research limitations/implications: This paper presents results for one alloy - AC AlSi9Cu only, for the assessment of the Silicon Modification Level didn’t include the arrangement of a Si crystal in a matrix.Originality/value: Original value of the work is applied the artificial intelligence for the assessment of the Silicon

  19. A High-Fe Aluminum Matrix Welding Filler Metal for Hardfacing Aluminum-Silicon Alloys

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A high-Fe containing aluminum matrix filler metal for hardfacing aluminum-silicon alloys has been developed by using iron,nickel,and silicon as the major strengthening elements,and by measuring mechanical properties,room temperature and high temperature wear tests,and microstructural analysis.The filler metal,which contains 3.0%-5.0% Fe and 11.0%-13.0% Si,exhibits an excellent weldability.The as-cast and as-welded microstructures for the filler metal are of uniformly distribution and its dispersed network of hard phase is enriched with Al-Si-Fe-Ni.The filler metal shows high mechanical properties and wear resistance at both room temperature and high temperatures.The deposited metal has a better resistance to impact wear at 220℃ than that of substrate Al-Si-Mg-Cu piston alloy;at room temperature,the deposited metal has an equivalent resistance to slide wear with lubrication as that of a hyper-eutectic aluminum-silicon alloy with 27% Si and 1% Ni.

  20. [The corrosion resistance of aluminum and aluminum-based alloys studied in artificial model media].

    Science.gov (United States)

    Zhakhangirov, A Zh; Doĭnikov, A I; Aboev, V G; Iankovskaia, T A; Karamnova, V S; Sharipov, S M

    1991-01-01

    Samples of aluminum and its alloys, designed for orthodontic employment, were exposed to 4 media simulating the properties of biologic media. The corrosion resistance of the tested alloys was assessed from the degree of aluminum migration to simulation media solutions, which was measured by the neutron activation technique. Aluminum alloy with magnesium and titanium has shown the best corrosion resistance. PMID:1799002

  1. Newly developed vacuum differential pressure casting of thin-walled complicated Al-alloy castings

    Directory of Open Access Journals (Sweden)

    Xuanpu DONG

    2005-05-01

    Full Text Available The newly designed vacuum differential pressure casting (VDPC unit was introduced, by which the capability of the VDPC process to produce thin-walled complicated Al-alloy castings, that are free from oxides, gas pore and shrinkage cavity and thus enhance overall part quality, was studied. Experimental results were compared with those of traditional gravity pouring and vacuum suction casting. The first series of experiments were focused on investigating thecastability of thin section Al-alloy casting. In the second series of experiments the metallographic evidence, casting strength and soundness were examined. Finally, case studies of very interesting thin walled complicated casting applications were described. The advantages of the described technique have made possible to produce thin walled complicated Al-alloy casting (up to a section thickness of 1 mm, which is not practical for gravity pouring and vacuum suction casting.

  2. and Carbon Fiber Reinforced 2024 Aluminum Alloy Composites

    Science.gov (United States)

    Kaczmar, Jacek W.; Naplocha, Krzysztof; Morgiel, Jerzy

    2014-08-01

    The microstructure and mechanical properties of 2024 aluminum alloy composite materials strengthened with Al2O3 Saffil fibers or together with addition of carbon fibers were investigated. The fibers were stabilized in the preform with silica binder strengthened by further heat treatment. The preforms with 80-90% porosity were infiltrated by direct squeeze casting method. The microstructure of the as-cast specimens consisted mainly of α-dendrites with intermetallic compounds precipitated at their boundaries. The homogenization treatment of the composite materials substituted silica binder with a mixture of the Θ phase and silicon precipitates distributed in the remnants of SiO2 amorphous phase. Outside of this area at the binder/matrix interface, fine MgO precipitates were also present. At surface of C fibers, a small amount of fine Al3C4 carbides were formed. During pressure infiltration of preforms containing carbon fibers under oxygen carrying atmosphere, C fibers can burn releasing gasses and causing cracks initiated by thermal stress. The examination of tensile and bending strength showed that reinforcing of aluminum matrix with 10-20% fibers improved investigated properties in the entire temperature range. The largest increase in relation to unreinforced alloy was observed for composite materials examined at the temperature of 300 °C. Substituting Al2O3 Saffil fibers with carbon fibers leads to better wear resistance at dry condition with no relevant effect on strength properties.

  3. Corrosion of aluminum alloys as a function of alloy composition

    International Nuclear Information System (INIS)

    A study was initiated which included nineteen aluminum alloys. Tests were conducted in high purity water at 3600C and flow tests (approx. 20 ft/sec) in reactor process water at 1300C (TF-18 loop tests). High-silicon alloys and AlSi failed completely in the 3600C tests. However, coupling of AlSi to 8001 aluminum suppressed the failure. The alloy compositions containing iron and nickel survived tht 3600C autoclave exposures. Corrosion rates varied widely as a function of alloy composition, but in directions which were predictable from previous high-temperature autoclave experience. In the TF-18 loop flow tests, corrosion penetrations were similar on all of the alloys and on high-purity aluminum after 105 days. However, certain alloys established relatively low linear corrosion rates: Al-0.9 Ni-0.5 Fe-0.1 Zr, Al-1.0 Ni-0.15 Fe-11.5 Si-0.8 Mg, Al-1.2 Ni-1.8 Fe, and Al-7.0 Ni-4.8 Fe. Electrical polarity measurements between AlSi and 8001 alloys in reactor process water at temperatures up to 1500C indicated that AlSi was anodic to 8001 in the static autoclave system above approx. 500C

  4. Effect of flask vibration time on casting integrity, Surface Penetration and Coating Inclusion in lost foam casting of Al-Si Alloy

    International Nuclear Information System (INIS)

    The paper presents the result of an experimental investigation conducted on medium aluminum silicon alloy casting- LM6, using no-vacuum assisted lost foam casting process. The study is directed for establishing the relationship between the flask vibrations times developed for molded sample on the casting integrity, surface penetration and coating inclusion defects of the casting. Four different flask vibration times namely 180, 120, 90 and 60 sec. were investigated. The casting integrity was investigated in terms of fulfilling in all portions and edges. The surface penetration was measured using optical microscope whilst image analyzer was used to quantify the percentage of coating inclusion in the casting. The results show that vibration time has significant influence on the fulfilling as well as the internal integrity of the lost foam casting. It was found that the lower vibration time produced comparatively sound casing.

  5. The influence of casting temperature on castability and structure of AJ62 alloy

    Directory of Open Access Journals (Sweden)

    A. Kiełbus

    2007-06-01

    Full Text Available Purpose: The AJ62 magnesium alloy exhibit good elevated-temperature tensile properties, excellent creep resistance and good castability. This alloy contains approximately 6% aluminum and about 2.5% strontium. Typically, it is used in automotive industry for the engine crankcase and power-train components. The aim of this paper is to present the results of the influence of pouring temperature on the fluidity and microstructure of the AJ62 magnesium alloy.Design/methodology/approach: The study was conducted on AJ62 magnesium alloys. Sand casting was performed at 695-755°C temperatures. The spiral test of fluidity was used. The microstructure was characterized by optical microscopy (Olympus GX-70 and a scanning electron microscopy (Hitachi S3400 equipped with an X-radiation detector EDS (VOYAGER of NORAN INSTRUMENTS. The phase identification of these alloys was identified by X-ray diffraction (JDX-75. Quantitative examination was conducted using the “MET-ILO” automatic image analysis programme.Findings: In as cast condition AJ62 alloy consisted of α-Mg grains with some types of intermetallic phases: (Al,Mg4Sr , Al8Mn5 and Al3Mg13Sr. The flow length and the intermetallicphases area fraction increase with increase the pouring temperature.Research limitations/implications: Future researches should contain investigations of the influence of casting temperature and heat treatment parameters on mechanical properties of AJ62 magnesium alloy.Practical implications: The established casting parameters (mainly temperature can be useful for preparing sand and die casting technology of the AJ62 magnesium alloy.Originality/value: The relationship between the initial structure, casting temperature, castability and phase composition in AJ62 magnesium alloy was specified.

  6. Modeling Mechanical Properties of Aluminum Composite Produced Using Stir Casting Method

    Directory of Open Access Journals (Sweden)

    Muhammad Hayat Jokhio

    2011-01-01

    Full Text Available ANN (Artificial Neural Networks modeling methodology was adopted for predicting mechanical properties of aluminum cast composite materials. For this purpose aluminum alloy were developed using conventional foundry method. The composite materials have complex nature which posses the nonlinear relationship among heat treatment, processing parameters, and composition and affects their mechanical properties. These nonlinear relation ships with properties can more efficiently be modeled by ANNs. Neural networks modeling needs sufficient data base consisting of mechanical properties, chemical composition and processing parameters. Such data base is not available for modeling. Therefore, a large range of experimental work was carried out for the development of aluminum composite materials. Alloys containing Cu, Mg and Zn as matrix were reinforced with 1- 15% Al2O3 particles using stir casting method. Alloys composites were cast in a metal mold. More than eighty standard samples were prepared for tensile tests. Sixty samples were given solution treatments at 580oC for half an hour and tempered at 120oC for 24 hours. The samples were characterized to investigate mechanical properties using Scanning Electron Microscope, X-Ray Spectrometer, Optical Metallurgical Microscope, Vickers Hardness, Universal Testing Machine and Abrasive Wear Testing Machine. A MLP (Multilayer Perceptron feedforward was developed and used for modeling purpose. Training, testing and validation of the model were carried out using back propagation learning algorithm. The modeling results show that an architecture of 14 inputs with 9 hidden neurons and 4 outputs which includes the tensile strength, elongation, hardness and abrasive wear resistance gives reasonably accurate results with an error within the range of 2-7 % in training, testing and validation.

  7. Microstructure modification by La2O3 and its effect on wear resistance properties of as-cast ZL107 alloy

    Institute of Scientific and Technical Information of China (English)

    WAN Diqing

    2010-01-01

    Modification of ZL107 aluminum alloy has been successfully achieved by using La2O3. The different casting parameters, including casting temperature as well as holding time and modifier content, were carried out to investigate the modification effects. The results show that the best modifier content is 1.0 wt.%, and the casting temperature has little effect. In addition, the wear behavior of modified and unmodified ZL107 has been compared. The wear resistance of as-cast ZL107 aluminum alloy can be significantly improved after modification.

  8. Calculation of Liquidus Temperature for Aluminum and Magnesium Alloys Applying Method of Equivalency

    OpenAIRE

    Mile B. Djurdjević; Srećko Manasijević; Zoran Odanović; Natalija Dolić

    2013-01-01

    The purpose of this paper is to develop a mathematical equation, which will be able to accurately predict the liquidus temperature of various aluminum and magnesium cast alloys on the basis of their known chemical compositions. An accurate knowledge of liquidus temperature permits a researcher to predict a variety of physical parameters pertaining to a given alloy. The analytical expressions presented in this paper are based on the “method of equivalency.” According to this concept, the influ...

  9. Numerical simulation of low pressure die-casting aluminum wheel

    Institute of Scientific and Technical Information of China (English)

    Mi Guofa; Liu Xiangyu; Wang Kuangfei; Fu Hengzhi

    2009-01-01

    The FDM numerical simulation software, ViewCast system, was employed to simulate the low pressure die casting (LPDC) of an aluminum wheel. By analyzing the mold-filling and solidification stage of the LPDC process, the distribution of liquid fraction, temperature field and solidification pattern of castings were studied. The potential shrinkage defects were predicted to be formed at the rim/spoke junctions, which is in consistence with the X-ray detection result. The distribution pattern of the defects has also been studied. A solution towards reducing such defects has been presented. The cooling capacity of the mold was improved by installing water pipes both in the side mold and the top mold. Analysis on the shrinkage defects under forced cooling mode proved that adding the cooling system in the mold is an effective method for reduction of shrinkage defects.

  10. Numerical simulation of low pressure die-casting aluminum wheel

    Directory of Open Access Journals (Sweden)

    Mi Guofa

    2009-02-01

    Full Text Available The FDM numerical simulation software, ViewCast system, was employed to simulate the low pressure die casting (LPDC of an aluminum wheel. By analyzing the mold-fi lling and solidifi cation stage of the LPDC process, the distribution of liquid fraction, temperature field and solidification pattern of castings were studied. The potential shrinkage defects were predicted to be formed at the rim/spoke junctions, which is in consistence with the X-ray detection result. The distribution pattern of the defects has also been studied. A solution towards reducing such defects has been presented. The cooling capacity of the mold was improved by installing water pipes both in the side mold and the top mold. Analysis on the shrinkage defects under forced cooling mode proved that adding the cooling system in the mold is an effective method for reduction of shrinkage defects.

  11. Twin-roll strip casting of magnesium alloys in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The development status of twin-roll strip casting for magnesium alloys in China was summarized as well as the new progress when several kinds of twin-roll strip casting technologies were developed and used.Horizontal twin-roll casting (HTRC) of magnesium alloys has attracted much attention and has been industrialized in China.Vertical twin roll casting(VTRC) of the magnesium alloys can reach a speed of higher than 30 m/min and its research and development are just beginning and exhibit exciting potential.By comparing the process characteristics of the two technologies,the process stability of HTRC for the magnesium alloys is better,and the casting speed and the cooling rate of VTRC for the magnesium alloys are higher.The quality of the products by the two technologies needs to be improved and further investigated.

  12. Preparation of composite aluminum automobile radiator by inversion casting

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The inversion casting technics of producing three-ply Al-Mn/Al-Si composite strap used in automobile radiator was studied. The physical processes of inversion casting, including the flux-supporting reacting and volatilizing at high temperature, the melting and solidification when the elements of solid and liquid fresh alloys meet with each other, the mutual diffusion of elements in solid and liquid, the crystallization and forming of metallurgical combination and the following rolling process, were analyzed. At the same time, the composite mechanism of this technique was also discussed.

  13. Galvanic aspects of aluminum sacrificial anode alloys in seawater.

    OpenAIRE

    Cummings, Jon Richard

    2012-01-01

    Galvanic aspects of aluminum sacrificial anode alloys in artificial seawater were investigated. Specifically, two mercury-bearing alloys and one tin-bearing alloy were studied. The polarization behavior of the aluminum sacrificial anode alloys coupled to HY-80 steel is discussed. Current versus time curves were obtained for aluminum/steel galvanic couples immersed in artificial seawater for specific intervals. Scanning elecron microscopy was used to characterize the anode dissolution patt...

  14. Quantification of Microsegregation in Cast Al-Si-Cu Alloys

    Science.gov (United States)

    Ganesan, M.; Thuinet, L.; Dye, D.; Lee, P. D.

    2007-08-01

    The random sampling approach offers an elegant yet accurate way of validating microsegregation models. However, both instrumental errors and interference from secondary phases complicate the treatment of randomly sampled microprobe data. This study demonstrates that the normal procedure of sorting the data for each element independently can lead to inaccurate estimation of segregation profiles within multicomponent, multiphase, aluminum alloys. A recently proposed alloy-independent approach is shown to more reliably isolate these interferences, allowing more accurate validation of microsegregation models. Application of this approach to examine solidification segregation of a 319-type alloy demonstrated that, for these slowly cooled castings, neither Sr or TiB2 additions significantly affected coring of Cu within the primary α-Al dendrites. Comparison against predictions of CALPHAD-type Gulliver-Scheil models was less satisfactory. Consideration of back-diffusion and morphology effects through a one-dimensional (1-D) numerical model do not improve the agreement. Possible reasons for the lack of agreement are hypothesized.

  15. Electric pulse treatment of welded joint of aluminum alloy

    Directory of Open Access Journals (Sweden)

    A.A. Mitiaev

    2013-08-01

    Full Text Available Purpose. Explanation of the redistribution effect of residual strengthes after electric pulse treatment of ark welding seam of the aluminum alloy. Methodology. Alloy on the basis of aluminium of АК8М3 type served as the research material. As a result of mechanical treatment of the ingots after alloy crystallization the plates with 10 mm thickness were obtained. After edge preparation the elements, which are being connected were butt welded using the technology of semiautomatic argon arc welding by the electrode with a diameter of 3 mm of AK-5 alloy. Metal structure of the welded joint was examined under the light microscope at a magnification of 200 and under the scanning electronic microscope «JSM-6360 LA». The Rockwell hardness (HRF was used as a strength characteristic of alloy. Hardness measuring of the phase constituents (microhardness was carried out using the device PМТ-3, with the indenter loadings 5 and 10 g. The crystalline structure parameters of alloy (dislocation density, second kind of the crystalline grid distortion and the scale of coherent scattering regions were determined using the methods of X-ray structural analysis. Electric pulse treatment (ET was carried out on the special equipment in the conditions of the DS enterprise using two modes A and В. Findings. On the basis of researches the previously obtained microhardness redistribution effect in the area of welded connection after ET was confirmed. As a result of use of the indicated treatment it was determined not only the reduction of microhardness gradient but also the simultaneous hardening effect in the certain thermal affected areas near the welding seam. During study of chemical composition of phase constituents it was discovered, that the structural changes of alloy as a result of ET first of all are caused by the redistribution of chemical elements, which form the connections themselves. By the nature of the influence the indicated treatment can be

  16. Mg-Al Alloys Manufactured by Casting and Hot Working Process

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Mechanical properties of Mg-Al based alloys at different fabrication state, namely as-cast, hot rolled, and annealed, were investigated to develop the alloys that are suitable for the casting/hot working process. Experimental results indicated that the castability such as hot cracking resistance tends to improve with increasing the aluminum content. However, the elongation at elevated temperatures was observed to decrease as the Al content increases, implying difficulties in hot forming. A small amount of Zr additions could significantly enhance the room temperature mechanical properties of hot-rolled Mg-6%Al-1%Zn alloy. The tendency of remarkable grain coarsening at high temperatures was effectively reduced by the Zr additions. TEM analyses suggested that very fine Al3Zr precipitates formed in the Zr-added alloy are responsible for the obtained results.

  17. Microstructure of AE44 magnesium alloy before and after hot-chamber die casting

    Directory of Open Access Journals (Sweden)

    A. Kiełbus

    2007-01-01

    Full Text Available Purpose: AE44 magnesium alloy allows attractive high temperature mechanical properties, as well as diecastabilityand good corrosion resistance. It contains magnesium, aluminum, cerium and lanthanum. Typically,it is used in automotive industry for structural components working at elevated temperature (150÷175°C. Theaim of this paper is to present the results of investigations on the microstructure of the AE44 magnesium alloybefore and after hot chamber die casting.Design/methodology/approach: Die casting was carried out on 280 tone locking force hot-chamber die castingmachine. For the microstructure observation, a Olympus GX+70 metallographic microscope and a HITACHIS-3400N scanning electron microscope with a Thermo Noran EDS spectrometer equipped with SYSTEM SIXwere used.Findings: Based on the investigation carried out it was found that the AE44 magnesium alloy before diecasting is characterized by α-Mg solid solution with globular, lamellar and acicular precipitations of Al11RE3and Al3RE phases. Moreover, there was found globular Mn-rich phase existence (probably Al8CeMn4 phase.After hot-chamber die casting the microstructure of AE44 alloys consist of equiaxed dendrites of α-Mg withprecipitates of Al11RE3 and probably Al2RE phase.Research limitations/implications: Future researches should contain investigations of the influence of the hotchamber die casting process parameters on the microstructure and mechanical properties of AE44 magnesiumalloy.Practical implications: AE44 magnesium alloy can be cast with cold- and hot-chamber die casting machine.Results of investigation may be useful for preparing die casting technology of this alloy.Originality/value: The results of the researches make up a basis for the investigations of new magnesium alloyscontaining rare earth elements for hot chamber die casting designed to service in elevated temperature.

  18. Influence of melting and filtration processes on the structure and mechanical properties of aluminum alloys

    Directory of Open Access Journals (Sweden)

    M. Dudyk

    2008-10-01

    Full Text Available In the article are presented the results of the study on the applied upgrading processes such as refining, modification and filtration of thenear eutectics alloy EN AC- 44000, AlSi11, (AK11, cast into the chill. The upgrading processes applied to the said alloy caused, incomparison to the alloy which was not upgraded, significant differences in the shape of the crystallization curves, obtained in the graphicrecord of the ATD-AED method. It was demonstrated the existence of connections between the thermal and electric phenomena duringsolidification and crystallization of the studied silumin. The obtained results of the metallographic analysis showed the occurrence of theimpurities within the alloy structure in the form of porosity and oxides following the metallurgical processing (in pig sows. The primarystudies on microstructure of the cast ceramic filters have demonstrated the purposefulness of introduction of the filtration process to thetechnology of aluminum alloys manufacturing. The microstructures of the filters cast with the studied alloys illustrate the extent anddeployment of the impurities retained (in the filter during the process of samples casting for measurement of the mechanical strengthproperties. On the example of the near eutectics alloy AK11, it has been demonstrated, that in comparison to the refined alloy there isa possibility to obtain significant improvement of mechanical properties, and especially elongation A5 and impact strength KCV.

  19. 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.

  20. Torsional Stability of Aluminum Alloy Seamless Tubing

    Science.gov (United States)

    Moore, R L; Paul, D A

    1939-01-01

    Torsion tests were made on 51ST aluminum-alloy seamless tubes having diameter-to-thickness ratios of from 77 to 139 and length-to-diameter ratios of from 1 to 60. The torsional strengths developed in the tubes which failed elastically (all tubes having lengths greater than 2 to 6 times the diameter) were in most cases within 10 percent of the value indicated by the theories of Donnel, Timoshenko, and Sturm, assuming a condition of simply supported ends.

  1. Aluminum alloy nanosecond vs femtosecond laser marking

    Indian Academy of Sciences (India)

    S Rusu; A Buzaianu; D G Galusca; L Ionel; D Ursescu

    2013-11-01

    Based on the lack of consistent literature publications that analyse the effects of laser marking for traceability on various materials, the present paper proposes a study of the influence of such radiation processing on an aluminum alloy, a vastly used material base within several industry fields. For the novelty impact, femtolaser marking has been carried out, besides the standard commercial nanosecond engraving. All the marks have been analysed using profilometry, overhead and cross-section SEM microscopy, respectively and EDAX measurements.

  2. Deuterium transport and trapping in aluminum alloys

    International Nuclear Information System (INIS)

    A simple model of diffusion and evolution of the density of deuterium in metals is presented. A model of the deuterium evolution in the presence of uniform and nonuniform distributions of traps, as well as perfectly reflecting and partially permeable boundary conditions is discussed. Computers are compared with experimental results describe deuterium distribution after fatigue crack growth of 2219 and 7075 aluminum alloys in a D2O water vapor environment and after ion implantation

  3. Roll bonding of 6061 aluminum alloy plates

    International Nuclear Information System (INIS)

    The roll bonding process is an important application of the solid state welding . in principle, two or more slabs of the materials to be bonded are placed in contact and welded around the edges. then, this assembled set is heated and rolled until the required thickness is obtained. this process is applied to clad the nuclear fuel, with high strength aluminum alloys during fabrication of plate type nuclear fuel elements for research reactors, or to produce many new constructions which have special uses in industrial applications. in the present work, the steps of the hot roll bonding of 6061 aluminum alloy plates were studies by using both microscopic examination and mechanical test namely singe lap shear strength test. also the effect of reduction degree in thickness, the sequence of hot rolling , surface roughness, degassing opening length and holding time on roll bonding process were studied. the results obtained due to variations in the above parameters are discussed with respect to their effects on the roll bonding of 6061 aluminum alloy plates as well as their effects on the specifications of the fuel plates

  4. Calculation of Liquidus Temperature for Aluminum and Magnesium Alloys Applying Method of Equivalency

    Directory of Open Access Journals (Sweden)

    Mile B. Djurdjević

    2013-01-01

    Full Text Available The purpose of this paper is to develop a mathematical equation, which will be able to accurately predict the liquidus temperature of various aluminum and magnesium cast alloys on the basis of their known chemical compositions. An accurate knowledge of liquidus temperature permits a researcher to predict a variety of physical parameters pertaining to a given alloy. The analytical expressions presented in this paper are based on the “method of equivalency.” According to this concept, the influence of any alloying element on the liquidus temperature of an aluminum and/or magnesium alloy can be translated into the equivalent influence of a reference element. Silicon as a reference element has been chosen for aluminum alloys and aluminum for magnesium alloys. The sum of the equivalent concentrations for other elements, when added to the influence of the actual reference element is used to calculate the liquidus temperature of the alloy. The calculated liquidus temperatures for wide ranges of alloy chemical compositions show a good correlation with corresponding measured liquidus temperatures.

  5. AI-Si-Cu-Mg(-Er)铸造铝合金的低周疲劳行为%Low-Cycle Fatigue Behavior of Cast AI-Si-Cu-Mg(-Er) Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    车欣; 徐志军; 陈立佳; 徐海健; 李锋

    2011-01-01

    对金属型铸造Al-Si-Cu-Mg和Al-Si-Cu-Mg-Er铝合金进行了疲劳试验,并研究了其室温下的低周疲劳行为.试验结果表明:金属型铸造Al-Si-Cu-Mg和Al-Si-Cu-Mg-Er铝合金表现为循环应变硬化和循环稳定,主要取决于外加总应变的高低;稀土元素Er的加入可提高金属型铸造Al-Si-Cu-Mg合金的循环变形抗力和疲劳寿命;金属型铸造Al-Si-Cu-Mg合金的塑性应变、弹性应变与断裂时的载荷反向次数之间呈直线关系,Al-Si-Cu-Mg-Er合金的弹性应变与疲劳断裂时的载荷反向次数之间也呈直线关系,但其塑性应变与疲劳断裂时的载荷反向次数之间则呈双线性关系.%Through the strain-controlled fatigue experiments, the low-cycle fatigue behavior of permanent-mold cast Al-Si-Cu-Mg and Al-Si-Cu-Mg-Er alloys at room temperature was investigated.The experimental results show that the Al-Si-Cu-Mg and Al-Si-Cu-Mg-Er alloys exhibit the cyclic strain hardening and cyclic stability, mainly depending on the imposed total strain amplitude. For the permanent-mold cast Al-Si-Cu-Mg alloy, the addition of Er can effectively enhance both cyclic deformation resistance and fatigue life of the alloys. A single-slope linear relation between plastic strain amplitude, elastic strain amplitude and reversals to failure is observed for permanent-mold cast Al-Si-Cu-Mg alloy. However, a two-slope linear relation between plastic strain amplitude and reversals to failure is noted for the Al-Si-Cu-Mg-Er alloy, although the corresponding relation between elastic strain amplitude and reversals to failure is linear.

  6. Thermal coatings for titanium-aluminum alloys

    Science.gov (United States)

    Cunnington, George R.; Clark, Ronald K.; Robinson, John C.

    1993-01-01

    Titanium aluminides and titanium alloys are candidate materials for use in hot structure and heat-shield components of hypersonic vehicles because of their good strength-to-weight characteristics at elevated temperature. However, in order to utilize their maximum temperature capability, they must be coated to resist oxidation and to have a high total remittance. Also, surface catalysis for recombination of dissociated species in the aerodynamic boundary layer must be minimized. Very thin chemical vapor deposition (CVD) coatings are attractive candidates for this application because of durability and very light weight. To demonstrate this concept, coatings of boron-silicon and aluminum-boron-silicon compositions were applied to the titanium-aluminides alpha2 (Ti-14Al-21Nb), super-alpha2 (Ti-14Al-23-Nb-2V), and gamma (Ti-33Al-6Nb-1Ta) and to the titanium alloy beta-21S (Ti-15Mo-3Al-3Nb-0.2Si). Coated specimens of each alloy were subjected to a set of simulated hypersonic vehicle environmental tests to determine their properties of oxidation resistance, surface catalysis, radiative emittance, and thermal shock resistance. Surface catalysis results should be viewed as relative performance only of the several coating-alloy combinations tested under the specific environmental conditions of the LaRC Hypersonic Materials Environmental Test System (HYMETS) arc-plasma-heated hypersonic wind tunnel. Tests were also conducted to evaluate the hydrogen transport properties of the coatings and any effects of the coating processing itself on fatigue life of the base alloys. Results are presented for three types of coatings, which are as follows: (1) a single layer boron silicon coating, (2) a single layer aluminum-boron-silicon coating, and (3) a multilayer coating consisting of an aluminum-boron-silicon sublayer with a boron-silicon outer layer.

  7. Evolution of microstructure in centrifugal cast Al-Cu alloy

    Directory of Open Access Journals (Sweden)

    Sui Yanwei

    2010-02-01

    Full Text Available In this research, the effects of centrifugal radius and mould rotation speed on microstructure in centrifugal-cast Al-Cu alloy have been investigated. The results show that, with increase of the centrifugal radius or mould rotation speed, the grain size of centrifugal-cast Al-Cu alloy decreases gradually, while the content of white phases containing the Al2Cu precipitated from α-phase, divorced eutectic and regular eutectic microstructure increases, leading to higher Cu macrosegregation. The variation level of microstructure in centrifugal-cast Al-Cu alloy at 600 rpm of mould rotation speed is greater than that at 300 rpm.

  8. Interplay among solidification, microstructure, residual strain and hot tearing in B206 aluminum alloy

    International Nuclear Information System (INIS)

    Hot tearing is a complex phenomenon attributed to alloy solidification, microstructure and stress/strain development within a casting. In this research, the conditions associated with the formation of hot tears in B206 aluminum alloy were investigated. Neutron diffraction strain mapping was carried out on three B206 castings with varying levels of titanium (i.e. unrefined, 0.02 and 0.05 wt%). Titanium additions effectively reduced grain size and transformed grain morphology from coarse dendrites to fine globular grains. Further, thermal analysis suggested that grain refinement delayed the onset of dendrite coherency in B206 and therefore enhanced the duration of bulk liquid metal feeding for the refined casting conditions. As a result, the interactive effects of such factors resulted in a more uniform distribution of strain, and subsequent higher resistance to hot tearing for the grain refined castings

  9. Casting of microstructured shark skin surfaces and possible applications on aluminum casting parts

    Directory of Open Access Journals (Sweden)

    Todor Ivanov

    2011-02-01

    Full Text Available Within the project Functional Surfaces via Micro- and Nanoscaled Structures?which is part of the Cluster of Excellence 揑ntegrative Production Technology?established and financed by the German Research Foundation (DFG, an investment casting process to produce 3-dimensional functional surfaces down to a structural size of 1 μm on near-net-shape-casting parts has been developed. The common way to realize functional microstructures on metallic surfaces is to use laser ablation, electro discharge machining or micro milling. The handicap of these processes is their limited productivity. The approach of this project to raise the efficiency is to use the investment casting process to replicate microstructured surfaces by moulding from a laser-microstructured grand master pattern. The main research objective deals with the investigation of the single process steps of the investment casting process with regard to the moulding accuracy. Actual results concerning making of the wax pattern, suitability of ceramic mould and core materials for casting of an AlSi7Mg0.3 alloy as well as the knock-out behavior of the shells are presented. By using of the example of an intake manifold of a gasoline race car engine, a technical shark skin surface has been realized to reduce the drag of the intake air. The intake manifold consists of an air-restrictor with a defined inner diameter which is microstructured with technical shark skin riblets. For this reason the inner diameter cannot be drilled after casting and demands a very high accuracy of the casting part. A technology for the fabrication and demoulding of accurate microstructured castings are shown. Shrinkage factors of different moulding steps of the macroscopic casting part as well as the microscopic riblet structure have been examined as well.

  10. The evaluation of dynamic cracking resistance of chosen casting alloys in the aspect of the impact bending test

    Directory of Open Access Journals (Sweden)

    J.Sadowski

    2008-10-01

    Full Text Available The increase of quality and durability of produced casting alloys can be evaluated on the base of material tests performed on a high level. One of such modern test methods are tests of the dynamic damage process of materials and the evaluation on the base of obtained courses F(f, F(t of parameters of dynamic cracking resistance KId, JId, performed with the usage of instrumented Charpy pendulums. In the paper there was presented the evaluation of dynamic cracking resistance parameters of casting alloys such as: AK12 aluminum alloy, L20G cast steel and spheroid cast iron. The methodology of the evaluation of that parameters was described and their change as well, for the AK12 alloy with the cold work different level, L20G cast steel cooled from different temperatures in the range +20oC -60oC, and for the spheroid cast iron in different stages of treatment i.e. raw state, after normalization, spheroid annealing and graphitizing annealing.Obtained parameters of dynamic cracking resistance KId, JId of tested casting alloys enabled to define the critical value of the ad defect that can be tolerated by tested castings in different work conditions with impact loadings.

  11. Non-metallic Inclusions in Continuously Cast Aluminum Killed Steels

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In aluminum killed steels, the size, shape, quantity and formation of non-metallic inclusions in ladle steel (before and after RH vacuum treatment) and in tundish as well as in slabs were studied by EPMA (Electron Probe Microanalysis) and by analyzing the total oxygen. The results showed that in the slabs the total oxygen was quite low and the inclusions discovered were mainly small-sized angular alumina inclusions. This indicates that most inclusions have been removed by floating out during the continuous casting process. In addition, the countermeasures were discussed to decrease the alumina inclusions in the slabs further.

  12. The Technological Improvements of Aluminum Alloy Coloring by Electrolysis

    Institute of Scientific and Technical Information of China (English)

    LI Nai-jun

    2004-01-01

    The technological process of coloring golden-tawny on aluminum alloy by electrolysis was improved in this paper. The optimum composition of electrolyte was found, the conditions of deposition and anodic oxidation by electrolysis were studied. The oxidative membrane on aluminum alloy was satisfying, the colored aluminum alloy by electrolysis is uniformity,bright and beautiful, and the coloring by electrolysis is convenient and no pollution.

  13. The in-situ Ti alloying of aluminum alloys and its application in A356 alloys

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This research has investigated the in-situ Ti alloying of aluminum alloys and its application to A356 alloys and wheels through the evaluation of microstructure and mechanical properties, The results showed that stable titanium content can be obtained by adding a small quantity of TiO2 into electrolyte of pure aluminum. Under this approach, a greater than 95% absorptivity of titanium was achieved, and the microstructure of the specimens was changed to fine equiaxed grains from coarse columnar grains in the pure aluminum. In comparison with the tradition A356 alloys and wheels, the corresponding microstructure in the testing A356 alloys and wheels was finer. Although the tensile strength was similar between the testing and the tradition A356 alloys and wheels, the ductility of the former (testing) is superior to that of the later (tradition), leading to an excellent combination of strength and ductility from the testing alloys and wheels.

  14. Microstructural and Statistical Study of Semisolid Casting of 6061 Alloy Using a Miniature Cooling Slope

    Science.gov (United States)

    Hajihashemi, Mahdi; Niroumand, Behzad; Shamanian, Morteza

    2014-10-01

    Preparation of metallic semisolid slurries using the cooling slope method is increasingly becoming popular because of the simplicity of design and control of the process. Microstructural features of the resultant semisolid castings such as size and sphericity of the primary particles are affected by several processing parameters such as pouring rate, cooling slope surface angle and length as well as the melt superheat. In this work, a miniature cooling slope for semisolid casting of small parts was built and attempts were made to develop an empirical relationship showing the correlation between the sphericity of the microstructure of semisolid cast 6061-aluminum alloy and the processing variables. The relationships were developed by a two-level factorial method. The results showed that the interaction of cooling slope length and pouring rate factors had the most effect on the sphericity of the final semisolid cast microstructure.

  15. Research progress of aluminum alloy automotive sheet and application technology

    Institute of Scientific and Technical Information of China (English)

    Ma Mingtu; You Jianghai; Lu Hongzhou; Wang Zhiwen

    2012-01-01

    Pretrcatment technology is deeply discussed to explain its importance in guaranteeing properties and form- ability of aluminum alloy automotive sheet. Some typical applications of aluminum alloy automotive sheet to automotive industry are listed. Based on the author's knowledge and recognition and research progress presently, the important re- search contents about aluminum alloy automotive sheet are emphasized. Reducing cost and price of sheet and going deeply into application research are the main work for expending the application of aluminum alloy automotive sheet in the automobile.

  16. Microstructure and fluidity of sand cast ZRE1 alloy

    Directory of Open Access Journals (Sweden)

    T. Rzychoń

    2008-02-01

    Full Text Available Purpose: The automotive use of magnesium is currently restricted to low-temperature structural components. Rare earth additions such as Ce, Nd, La and Pr are known to improve the creep performance. The aim of the research was to determine the effect of pouring temperature on the as-cast microstructure of ZRE1 magnesium alloy.Design/methodology/approach: The study was conducted on Mg-3Zn-3RE-0.5Zr (ZRE1 alloy after cast in different conditions. The microstructure was characterized by optical microscopy (Olympus GX-70 and a scanning electron microscopy (Hitachi S3400 equipped with an X-radiation detector EDS (VOYAGER of NORAN INSTRUMENTS. The phase composition of these alloys was identified by X-ray diffraction (JDX-75. A program for image analysis Met-ilo was used for determination of area fraction of intermetallic phases.Findings: The microstructure of ZRE1 alloy consists of α-Mg solid solution with Mg12RE phase. Pouring temperature has an influence on the fluidity and microstructure.Research limitations/implications: The future research will contain creep tests and microstructural investigations of cast and die-cast alloys using TEM microscopy.Practical implications: Results of investigation may be useful for preparation of sand casting technology of the Mg-Zn-RE-Zr alloys.Originality/value: This paper includes the results of microstructural investigations and effects of pouring temperature on the fluidity of ZRE1 magnesium alloy for gravity casting technology.

  17. Manufacture of centrifugal Castings

    OpenAIRE

    Minář, Martin

    2015-01-01

    The main goal of this bachelor thesis is to collect basic information related to the production of castings by centrifugal casting. It is focused on horizontal and vertical centrigugal casting, casting of various metals and their alloys, such as zinc, aluminum, iron, steel and silumin. This technology is compared with other casting methods in terms of specific characteristics, amount of usage, production economics, advantages, disadvantages, the resulting quality of castings and other factors.

  18. Solid-particle erosion behavior of cast alloys used in the mining industry

    Institute of Scientific and Technical Information of China (English)

    Hakan Atapek; Sinan Fidan

    2015-01-01

    The erosive-wear response of five commercial ferrous-based cast alloys used for crushing was examined in this study. The micro-structures of the alloys were modified to elucidate the effect of microstructural features on wear. Erosion tests were conducted using alumi-num oxide particles (90–125 µm) at 70 m/s and a normal impact angle (90°). The worn surfaces were characterized by scanning electron mi-croscopy and 3D non-contact laser profilometry. It is found that (i) a pearlitic structure exhibiting a greater plastic deformation than both bainitic and martensitic structures shows the greatest resistance to erosive wear at normal impact and (ii) the fracture characteristics of car-bide and graphite particles plays an important role in determining the erosion wear behavior of the cast alloy matrices.

  19. Numerical simulation of residual thermal stresses in AA7050 alloy during DC-casting using ALSIM5

    NARCIS (Netherlands)

    Lalpoor, M.; Eskin, D.G.; Katgerman, L.

    2010-01-01

    Non-homogenous cooling rates and solidification conditions during DC-casting of high strength aluminum alloys result in the formation and accumulation of residual thermal stresses with different signs and magnitudes in different locations of the billet. Rapid propagation of microcracks in the presen

  20. THE FATIGUE CRACK PROPAGATION BEHAVIOR AND CRACK DEFLECTION OF A357 CASTING ALUMINUM ALLOYS%A357铸造铝合金疲劳裂纹扩展行为以及裂纹偏折

    Institute of Scientific and Technical Information of China (English)

    徐芳; 陈振中

    2011-01-01

    The fatigue crack propagation behavior of A357 casting aluminum alloys at stress ratios of 0.05 and 0.7 under T5 and T6 heat treatments were studied and crack propagation curves were modified by a crack deflection model. The research results show that the fatigue crack grows along the boundary of dendrite cells to cause a remarkable crack deflection. The fatigue crack propagation rate at r=0.05 is smaller than that at r=0.7 for both T5 and T6 heat treatments. The effect of heat treatment on the fatigue crack propagation rates cannot be seen. The fatigue crack propagation rates modified by the crack deflection model predict no change at r=0.7, while a remarkable increase of the fatigue crack propagation rates can be seen at r=0.05. It is more reasonable and accurate to use the effective stress intensity factors for Mode Ⅰand Ⅱ to describe the fatigue crack propagation rates when a crack deflection occurs.%该文研究了A357铸造铝合金在T5/T6两种热处理条件、应力比为0.05和0.7时的疲劳裂纹扩展行为,并用裂纹偏折模型对裂纹扩展速率曲线进行修正。研究结果表明,裂纹沿着树状晶边界扩展导致显著的裂纹偏折。在T5/T6两种热处理条件下,应力比r=0.05时的裂纹扩展速率均远小于应力比为0.7时的裂纹扩展速率,热处理方式对裂纹扩展速率没有影响。应力比r=0.7时,偏折裂纹模型修正后的裂纹扩展速率没有明显变化;而应力比r=0.05时,偏折裂纹模型修正后的裂纹扩展速率较修正前有显著增加。裂纹发生偏折时,采用同时考虑Ⅰ型和Ⅱ型裂纹的裂纹尖端有效应力强度因子描述裂纹扩展速率更合理也更准确。

  1. Casting Porosity-Free Grain Refined Magnesium Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Schwam, David [Case Western Reserve University

    2013-08-12

    The objective of this project was to identify the root causes for micro-porosity in magnesium alloy castings and recommend remedies that can be implemented in production. The findings confirm the key role played by utilizing optimal gating and risering practices in minimizing porosity in magnesium castings. 

  2. Evaluation of Cast Al-Si-Fe alloy/Coconut Shell Ash Particulate Composites

    OpenAIRE

    S.Y. Aku; D.S. Yawas; ADOKMA, Apasi

    2013-01-01

    Al-7wt%Si-2wt%Fe alloy/Coconut shell ash(CSAp) composites having 3-15wt%coconut shell ash were fabricated by double stir-casting method.  The microstructure, hardness values and density of the composites were evaluated. The density of the composites decreased as the percentage of coconut shell ash increases in the aluminum alloy. This means that composites of lower weight component can be produced by adding CSAp.  Microstructural analysis showed fairy distribution of coconut shell a...

  3. Effect of substituting cerium-rich mischmetal with lanthanum on high temperature properties of die-cast Mg-Zn-Al-Ca-RE alloys

    International Nuclear Information System (INIS)

    Mg-Zn-Al-Ca-RE alloys have been found to be promising materials for substituting aluminum alloys used for automatic transmission case applications in the automobile industry. Particularly, Mg-0.5%Zn-6%Al-1%Ca-3%RE (ZAXE05613) alloy exhibits comparable creep resistance as ADC12 die-casting aluminum alloy that is currently used for automatic transmission case applications. Changing the rare earth (RE) content of the alloy from mischmetal to lanthanum gives a further improvement in the creep properties of the alloy. Lanthanum addition results in the crystallization of a large amount of acicular Al11RE3 (Al11La3) compound along the grain boundaries as well as across the grain boundaries and this effectively controls grain boundary sliding and dislocation motion in the vicinity of the grain boundaries. As a result, die-cast ZAXLa05613 alloy exhibits a higher creep resistance than that of ZAXE05613 alloy

  4. 76 FR 5840 - The Basic Aluminum Castings Co., Cleveland, OH; Notice of Revised Determination on Reconsideration

    Science.gov (United States)

    2011-02-02

    ... was published in the Federal Register on November 3, 2010 (75 FR 67773). Workers at the subject firm... Employment and Training Administration The Basic Aluminum Castings Co., Cleveland, OH; Notice of Revised... Assistance (TAA) applicable to workers and former workers of The Basic Aluminum Castings Co., Cleveland,...

  5. Laser perforation of aluminum alloy sheet

    Science.gov (United States)

    Migliore, Leonard; Nazary, George

    2010-02-01

    Recent advances in the design of gain modules for diode-pumped solid-state lasers have allowed the manufacture of high-powered Q-switched products. The high available pulse energy and good mode quality enable highly efficient harmonic conversion, enabling the generation of several hundred watts of average power at a wavelength of 532nm. Among the applications for which this class of product may be suited is the rapid drilling of small-diameter holes in aluminum sheet. To investigate this application, plates of several aluminum alloys were drilled under a variety of conditions. The drilled plates were sectioned and subjected to analysis by optical metallography. The initial results indicate ways in which the process may be optimized.

  6. Interaction between alloying and hardening of cast iron surface

    Institute of Scientific and Technical Information of China (English)

    刘政军; 郝雪枫; 傅迎庆; 牟力军

    2002-01-01

    To improve wear resistance of surface will increase the service life of gray cast iron directly. This paper presents that gray cast iron surface coated with alloy powder is locally remelted by TIG arc to increase the wear resistance. The influences of arc current and scanning rate etc on surface properties are found. Under different conditions, the microstructure, hardness and wear resistance of remelted layer are analyzed and measured. The results indicate that the gray cast iron surface can be strengthened by TIG arc local remelting treatment. Especially, surface alloying hardening effect is best and surface properties are improved remarkably.

  7. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  8. The quality of the joint between alloy steel and unalloyed cast steel in bimetallic layered castings

    Directory of Open Access Journals (Sweden)

    T. Wróbel

    2012-01-01

    Full Text Available In paper is presented technology of bimetallic layered castings based on founding method of layer coating directly in cast process so-called method of mould cavity preparation. Prepared castings consist two fundamental parts i.e. bearing part and working part (layer. The bearing part of bimetallic layered casting is typical foundry material i.e. ferritic-pearlitic unalloyed cast steel, whereas working part (layer is plate of austenitic alloy steel sort X2CrNi 18-9. The ratio of thickness between bearing and working part is 8:1. The aim of paper was assessed the quality of the joint between bearing and working part in dependence of pouring temperature and carbon concentration in cast steel. The quality of the joint in bimetallic layered castings was evaluated on the basis of ultrasonic non-destructive testing, structure and microhardness researches.

  9. Hydrogen solubility in aluminum-copper alloys

    International Nuclear Information System (INIS)

    Hydrogen solubility(S (10-2 cm3g-1atm-0.5)) in Al-(0-50mass%) Cu alloys were measured by a desorption technique for the thermally gas-charged cylindrical samples which were solidified unidirectionally in the pure nitrogen gas flow (sample ND). The solubility was compared with that in samples melted and cast in vacuum (sample VM) and with that in samples melted in air and cast into a metal mould (sample AM). Since the solubility S (ND) was almost equal to S (VM), samples ND were found to have no voids of gas defects such as porosity and cavity. In the region of α-solid solution (Cuθ) and got to the higher hydrogen solubility in the θ-phase (Sθ), according to the equation S (ND) = Sα (1-fθ) + Sθfθ. S (AM) was greater than S (ND) due to the trapped hydrogen gas in the voids. In the alloy of the eutectic composition (33 mass%Cu) which had little voids, S (33AM) was smaller than S (33ND). This was attributed to anon-equilibrium or suppressed charging of hydrogen due to the trapping of hydrogen in a finer metallic structure of a sample AM. (author)

  10. SOLUBILITY OF SILICON IN CAST ALUMINIUM ALLOY AFTER ELECTROHYDROPULSE TREATMENT

    OpenAIRE

    Dyachenko, S.; Fedchenko, N.

    2006-01-01

    The structure of cast aluminium alloy AЛ9 exposed to electrohydropulse treatment (EHPT) was studied. It has been shown that after EHPT solubility of silicon in alloy matrix was increased. With the help of thermodynemic analysis the structural changes in metal after EHPT were explained.

  11. Thixo forging process of wrought aluminum alloy fabricated by rotational helical shape stirrer

    International Nuclear Information System (INIS)

    The manufacture of rheology materials from wrought and casting aluminum alloys using controlling solid fraction and crystal grain is demonstrated in this paper. The equipment to form the rheology material was designed so that shear force and applied pressure could be carefully and simultaneously applied using a mechanical stirrer. The problems caused by using this method with the thixo forging process were studied by investigating the mechanical properties of a sample that had a controlled solid fraction of 45-50 %

  12. NBS: Nondestructive evaluation of nonuniformities in 2219 aluminum alloy plate: Relationship to processing

    Science.gov (United States)

    Swartzendruber, L.; Boettinger, W.; Ives, L.; Coriell, S.; Ballard, D.; Laughlin, D.; Clough, R.; Biancanieilo, F.; Blau, P.; Cahn, J.

    1980-01-01

    The compositional homogeneity, microstructure, hardness, electrical conductivity and mechanical properties of 2219 aluminum alloy plates are influenced by the process variables during casting, rolling and thermomechanical treatment. The details of these relationships wre investigated for correctly processed 2219 plate as well as for deviations caused by improper quenching after solution heat treatment. Primary emphasis was been placed on the reliability of eddy current electrical conductivity and hardness as NDE tools to detect variations in mechanical properties.

  13. Impurity control and corrosion resistance of magnesium-aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, M. [GM China Lab; Song, GuangLing [ORNL

    2013-01-01

    The corrosion resistance of magnesium alloys is very sensitive to the contents of impurity elements such as iron. In this study, a series of diecast AXJ530 magnesium alloy samples were prepared with additions of Mn and Fe. Through a comprehensive phase diagram calculation and corrosion evaluation, the mechanisms for the tolerance limit of Fe in magnesium alloy are discussed. This adds a new dimension to control the alloying impurity in terms of alloying composition design and casting conditions.

  14. Impression creep properties of a semi-solid processed magnesium-aluminum alloy containing calcium and rare earth elements

    International Nuclear Information System (INIS)

    The creep properties of a thixoformed magnesium-aluminum alloy containing calcium and rare earth elements were studied under shear modulus-normalized stresses ranging from 0.0225 to 0.035 at temperatures of 150-212 oC using the impression creep technique. Analysis of the creep mechanism based on a power-law equation indicated that pipe diffusion-controlled dislocation climb is the dominant mechanism during creep. The alloy has a better creep resistance than high-pressure die-cast magnesium-aluminum alloy.

  15. Precipitate-Accommodated Plasma Nitriding for Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    Patama Visittipitukul; Tatsuhiko Aizawa; Hideyuki Kuwahara

    2004-01-01

    Reliable surface treatment has been explored to improve the strength and wear resistance of aluminum alloy parts in automotives. Long duration time as well as long pre-sputtering time are required for plasma nitriding of aluminum or its alloys only with the thickness of a few micrometers. New plasma inner nitriding is proposed to realize the fast-rate nitriding of aluminum alloys. Al-6Cu alloy is employed as a targeting material in order to demonstrate the effectiveness of this plasma nitriding. Mechanism of fast-rate nitriding process is discussed with consideration of the role of Al2Cu precipitates.

  16. Using Neural Networks to Predict the Hardness of Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    B. Zahran

    2015-02-01

    Full Text Available Aluminum alloys have gained significant industrial importance being involved in many of the light and heavy industries and especially in aerospace engineering. The mechanical properties of aluminum alloys are defined by a number of principal microstructural features. Conventional mathematical models of these properties are sometimes very complex to be analytically calculated. In this paper, a neural network model is used to predict the correlations between the hardness of aluminum alloys in relation to certain alloying elements. A backpropagation neural network is trained using a thorough dataset. The impact of certain elements is documented and an optimum structure is proposed.

  17. Market Opportunity of Some Aluminium Silicon Alloys Materials through Changing the Casting Process

    Directory of Open Access Journals (Sweden)

    Delfim SOARES

    2012-08-01

    Full Text Available Fatigue is considered to be the most common mechanism by which engineering components fail, and it accounts for at least 90% of all service failures attributed to mechanical causes. Mechanical properties (tensile strength, tensile strain, Young modulus, etc as well as fatigue properties (fatigue life are very dependent on casting method. The most direct effects of casting techniques are on the metallurgical microstructure that bounds the mechanical properties. One of the important variables affected by the casting technique is the cooling rate which is well known to strongly restrict the microstructure. In the present research has been done a comparison of fatigue properties of two aluminum silicon alloys obtained by two casting techniques. It was observed that the fatigue life is increasing with 24% for Al12Si and 31% for AL18Si by using centrifugal casting process instead of gravity casting. This increasing in fatigue life means that a component tailored from materials obtained by centrifugal casting will stay longer in service. It was made an estimation of the time required to recover the costs of technology in order to use the centrifuge process that will allow to obtain materials with improved properties. The amortization can be achieved by using two different marketing techniques: through the release of the product at the old price and with much longer life of the component which means "same price - longer life", or increasing price, by highlighting new product performance which means "higher price - higher properties".

  18. Influence of Al addition on structure of magnesium casting alloys

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2006-04-01

    Full Text Available Purpose: In the following paper there have been the structure and properties of the MCMgAl9Zn1 magnesium cast alloy as-cast state and after a heat treatment presented.Design/methodology/approach: A casting cycle of alloys has been carried out in an induction crucible furnace using a protective salt bath Flux 12 equipped with two ceramic filters at the melting temperature of 750±10ºC, suitable for the manufactured material. The following results concern transmission and scanning microscopy, X-ray qualitative and quantitative microanalysis.Findings: The analysis of the thin foils after the ageing process has confirmed that the structure of the magnesium cast alloy consists of the solid solution α – Mg (matrix of the secondary phase β – Mg17Al12 evenly located in the structure. The structure creates agglomerates in the form of needle precipitations, partially coherent with the matrix placed mostly at the grain boundaries.Research limitations/implications: According to the alloys characteristic, the applied cooling rate and alloy additions seems to be a good compromise for mechanical properties and microstructures, nevertheless further tests should be carried out in order to examine different cooling rates and parameters of solution treatment process and aging process.Practical implications: A desire to create as light vehicle constructions as possible and connected with it low fuel consumption have made it possible to make use of magnesium alloys as a constructional material in automotive industry.Originality/value: The undertaken examinations aim at defining the influence of a chemical composition and precipitation processes on the structure and casting magnesium alloy properties in its as-cast state and after heat treatment with a different content of alloy components.

  19. Processing of Aluminum Alloys Containing Displacement Reaction Products

    OpenAIRE

    Stawovy, Michael Thomas

    1998-01-01

    Aluminum and metal-oxide powders were mixed using mechanical alloying. Exothermic displacement reactions could be initiated in the powders either by mechanical alloying alone or by heat treating the mechanically alloyed powders. Exponential relationships developed between the initiation time of the reaction and the mechanical alloying charge ratio. The exponential relationships were the result of changes in the intensity and quantity of collisions occurring during mechanical alloying. Di...

  20. The Effect of Aluminum Content on the Microstructure and Cavitation Wear of Feal Intermetallic Alloys

    Directory of Open Access Journals (Sweden)

    Jasionowski Robert

    2014-03-01

    Full Text Available Intermetallic-based alloys (so called intermetallics of the Fe-Al binary system are modern construction materials, which in recent decades have found application in many branches of the power, chemical and automotive industries. High resistance of FeAl based alloys to cavitational erosion results first of all from their high hardness in the as-cast state, large compressive stresses in the material, as well as homogeneous structure. In the present paper, the effect of aluminum content on the microstructure, texture and strain implemented upon cavitation wear of FeAl intermetallic alloys, have been analyzed by field emission gun scanning electron microscopy (FEG SEM and electron backscatter diffraction (EBSD analysis. Obtained results of structural characterization indicates that with increasing aluminium content effects of orientation randomization (weakening of //ND casting texture, grain refinement and rising of mechanical strenght (and so cavitational resistance take place.

  1. Quality analysis of the Al-Si-Cu alloy castings

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2007-04-01

    Full Text Available The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all - to reduce the amount of the waste products. Method was developed for analysis of the casting defects images obtained with the X-ray detector analysis of the elements made from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type as well as the method for classification of casting defects using the artificial intelligence tools, including the neural networks; the developed method was implemented as software programs for quality control. Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the “Cosworth” technological process. The computer system, in which the artificial neural networks as well as the automatic image analysis methods were used makes automatic classification possible of defects occurring in castings from the Al-Si-Cu alloys, assisting and automating in this way the decisions about rejection of castings which do not meet the defined quality requirements, and therefore ensuring simultaneously the repeatability and objectivity of assessment of the metallurgical quality of these alloys.

  2. Analysis and Evaluation of Novel Al-Mg-Sc-Zr Aerospace Alloy Strip Produced Using the Horizontal Single Belt Casting (HSBC) Process

    Science.gov (United States)

    Ge, Sa; Celikin, Mert; Isac, Mihaiela; Guthrie, Roderick I. L.

    2015-04-01

    Horizontal single belt casting (HSBC) is a near net shape casting process in which molten metal is directly cast into thin strips, at high cooling rates (order of several 100 °C/s), with the potential for high volume, friction free, continuous production of metal strips. This casting process was used in the present work to produce strips of Al-Mg alloys in the AA5000 series, with additions of Sc and Zr. Such aluminum alloys show exceptional potential as a structural material for transportation/aerospace applications. To demonstrate the suitability of the HSBC process to manufacture competitive strip products of Al-Mg-Sc-Zr, the mechanical properties and microstructures of the strips produced using the HSBC process were compared with conventionally cast products. The effects of annealing on the mechanical properties of the strip-cast Al-Mg-Sc-Zr alloys were also investigated.

  3. Microstructure and properties of 2618-Ti heat resistant aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    王建华; 易丹青; 王斌

    2003-01-01

    The mechanical properties of alloy 2618 with 0.5%(mass fraction) titanium and its microstructures in different states such as as-cast and quenching-aging were investigated. Titanium was added into the alloy with Al-5%Ti master alloy that was extruded severely. Al3Ti particles in the microstructure of cast alloy 2618-Ti are very small because those of master alloy are also small. When titanium is used as an alloying element, it does not affect the morphology of Al9FeNi phase in cast alloy, but decreases the grain size of as-cast alloy remarkably. The grain size of quenching-aging alloy 2618 decreases apparently due to the existence of a great deal of dispersive Al3Ti particles. Adding 0.5%Ti has no effect on the room temperature tensile properties of alloy 2618, but apparently increases the elevated temperature instantaneous tensile properties and that of the alloy which is exposed at 250 ℃ for 100 h.

  4. Microstructure, tensile properties and fracture behavior of high temperature Al–Si–Mg–Cu cast alloys

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, A.M.A., E-mail: madel@uqac.ca [Center for Advanced Materials, Qatar University, Doha (Qatar); Department of Metallurgical and Materials Engineering, Faculty of Petroleum and Mining Engineering, Suez Canal University, Box 43721, Suez (Egypt); Samuel, F.H. [Université du Québec à Chicoutimi, Chicoutimi, QC, Canada G7H 2B1 (Canada); Al Kahtani, Saleh [Industrial Engineering Program, Mechanical Engineering Department, College of Engineering, Salman bin Abdulaziz University, Al Kharj (Saudi Arabia)

    2013-08-10

    The high temperature tensile behavior of 354 aluminum cast alloy was investigated in the presence of Zr and Ni. The cast alloys were given a solutionizing treatment followed by artificial aging at 190 °C for 2 h. High temperature tensile tests were conducted at various temperatures from 25 °C to 300 °C. Optical microscopy and electron probe micro-analyzer were used to study the microstructure of different intermetallic phases formed. The fractographic observations of fracture surface were analyzed by scanning electron microscopy to understand the fracture mechanism. The results revealed that the intermetallics phases of (Al, Si){sub 3}(Zr, Ti), Al{sub 3}CuNi and Al{sub 9}NiFe are the main feature in the microstructures of alloys with Zr and Ni additions. The results also indicated that the tensile strength of alloy decreases with an increase in temperature. The combined addition of 0.2 wt% Zr and 0.2 wt% Ni leads to a 30% increase in the tensile properties at 300 °C compared to the base alloy. Zr and Ni bearing phases played a vital role in the fracture mechanism of the alloys studied.

  5. Microstructure, tensile properties and fracture behavior of high temperature Al–Si–Mg–Cu cast alloys

    International Nuclear Information System (INIS)

    The high temperature tensile behavior of 354 aluminum cast alloy was investigated in the presence of Zr and Ni. The cast alloys were given a solutionizing treatment followed by artificial aging at 190 °C for 2 h. High temperature tensile tests were conducted at various temperatures from 25 °C to 300 °C. Optical microscopy and electron probe micro-analyzer were used to study the microstructure of different intermetallic phases formed. The fractographic observations of fracture surface were analyzed by scanning electron microscopy to understand the fracture mechanism. The results revealed that the intermetallics phases of (Al, Si)3(Zr, Ti), Al3CuNi and Al9NiFe are the main feature in the microstructures of alloys with Zr and Ni additions. The results also indicated that the tensile strength of alloy decreases with an increase in temperature. The combined addition of 0.2 wt% Zr and 0.2 wt% Ni leads to a 30% increase in the tensile properties at 300 °C compared to the base alloy. Zr and Ni bearing phases played a vital role in the fracture mechanism of the alloys studied

  6. Effect of Yb additions on microstructures and properties of 7A60 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    FANG Hua-chan; CHEN Kang-hua; ZHANG Zhuo; ZHU Chang-jun

    2008-01-01

    Al-Zn-Mg-Cu-Zr alloys containing Yb were prepared by cast metallurgy. Effect of 0.30% Yb additions on the microstructure and properties of 7A60 aluminum alloys with T6 and T77 aging treatments was investigated by TEM, optical microscopy, hardness and electric conductivity measurement, tensile test and stress corrosion cracking test. The results show that the Yb additions to high strength Al-Zn-Mg-Cu-Zr aluminum alloys can produce fine coherent dispersoids. Those dispersoids can strongly pin dislocation and subgrain boundaries, which can significantly retard the recrystallization by inhibiting the nucleation of recrystallization and the growth of subgrains and keeping low-angle subgrain boundaries. Yb additions can obviously enhance the resistance to stress corrosion cracking and the fracture toughness property, and mildly increase the strength and ductility with T6 and T77 treatments.

  7. Effect and kinetic mechanism of ultrasonic vibration on solidification of 7050 aluminum alloy

    Directory of Open Access Journals (Sweden)

    Ripeng Jiang

    2014-07-01

    Full Text Available The work described in this paper dealt with the effect of ultrasonic vibration on the solidification of 7050 aluminum alloy. Two experiments were carried out through introducing ultrasound into the semi-continuous direct-chill (DC casting of aluminum alloy and into alloy solidifying in a crucible, respectively. Results show that ultrasonic vibration can refine grains in the whole cross-section of a billet in the first experiment and is able to increase the cooling rate within the temperature range from 625 °C to 590 °C in the other one. The mechanism of particle resonance caused by ultrasonic vibration was illustrated on the basis of theoretical analysis of the kinetics and energy conversion during the solidification. It is demonstrated that the kinetic energy of resonant particles are mainly from the latent heat energy of solidification, which can shorten the cooling time, inhibit the crystal growth and then lead to the grain refinement.

  8. A method to study the history of a double oxide film defect in liquid aluminum alloys

    Science.gov (United States)

    Raiszadeh, R.; Griffiths, W. D.

    2006-12-01

    Entrained double oxide films have been held responsible for reductions in mechanical properties in aluminum casting alloys. However, their behavior in the liquid metal, once formed, has not been studied directly. It has been proposed that the atmosphere entrapped in the double oxide film defect will continue to react with the liquid metal surrounding it, perhaps leading to its elimination as a significant defect. A silicon-nitride rod with a hole in one end was plunged into liquid aluminum to hold a known volume of air in contact with the liquid metal at a constant temperature. The change in the air volume with time was recorded by real-time X-ray radiography to determine the reaction rates of the trapped atmosphere with the liquid aluminum, creating a model for the behavior of an entrained double oxide film defect. The results from this experiment showed that first oxygen, and then nitrogen, was consumed by the aluminum alloy, to form aluminum oxide and aluminum nitride, respectively. The effect of adding different elements to the liquid aluminum and the effect of different hydrogen contents were also studied.

  9. Heat treatment impact on the structure of die-cast magnesium alloys

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2007-01-01

    Full Text Available Purpose: In the following paper there have been the structure and properties of the MCMgAl6Zn1 magnesiumcast alloy as-cast state and after a heat treatment presented.Design/methodology/approach: A casting cycle of alloys has been carried out in an induction crucible furnaceusing a protective salt bath Flux 12 equipped with two ceramic filters at the melting temperature of 750±10ºC,suitable for the manufactured material. The following results concern light and scanning microscopy, X-rayqualitative and quantitative microanalysis.Findings: The results of the EDS chemical composition analysis confirm the presence of magnesium, aluminum,manganese, and zinc, constituting the structure of α solid solution with the Mg17Al12 placed mainly on the grainorder in the form of plates, also the phase AlMnFe with irregular shape, occurred often in the shape of blocksor needles and the Laves phase Mg2Si.Research limitations/implications: According to the alloys characteristic, the applied cooling rate and alloyadditions seems to be a good compromise for mechanical properties and microstructures, nevertheless furthertests should be carried out in order to examine different cooling rates and parameters of solution treatmentprocess and aging process.Practical implications: A desire to create as light vehicle constructions as possible and connected with itlow fuel consumption have made it possible to make use of magnesium alloys as a constructional material inautomotive industry.Originality/value: The undertaken examinations aim at defining the influence of a chemical composition andprecipitation processes on the structure and casting magnesium alloy properties in its as-cast state and after heattreatment with a different content of alloy components.

  10. Fabrication of Aluminum Tubes Filled with Aluminum Alloy Foam by Friction Welding

    Directory of Open Access Journals (Sweden)

    Yoshihiko Hangai

    2015-10-01

    Full Text Available Aluminum foam is usually used as the core of composite materials by combining it with dense materials, such as in Al foam core sandwich panels and Al-foam-filled tubes, owing to its low tensile and bending strengths. In this study, all-Al foam-filled tubes consisting of ADC12 Al-Si-Cu die-cast aluminum alloy foam and a dense A1050 commercially pure Al tube with metal bonding were fabricated by friction welding. First, it was found that the ADC12 precursor was firmly bonded throughout the inner wall of the A1050 tube without a gap between the precursor and the tube by friction welding. No deformation of the tube or foaming of the precursor was observed during the friction welding. Next, it was shown that by heat treatment of an ADC12-precursor-bonded A1050 tube, gases generated by the decomposition of the blowing agent expand the softened ADC12 to produce the ADC12 foam interior of the dense A1050 tube. A holding time during the foaming process of approximately tH = 8.5 min with a holding temperature of 948 K was found to be suitable for obtaining a sound ADC12-foam-filled A1050 tube with sufficient foaming, almost uniform pore structures over the entire specimen, and no deformation or reduction in the thickness of the tube.

  11. Microstructural evolution of direct chill cast Al-15.5Si-4Cu-1Mg-1Ni-0.5Cr alloy during solution treatment

    OpenAIRE

    He Kezhun; Yu Fuxiao; Zhao Dazhi

    2011-01-01

    Heat treatment has important influence on the microstructure and mechanical properties of Al-Si alloys. The most common used heat treatment method for these alloys is solution treatment followed by age-hardening. This paper investigates the microstructural evolution of a direct chill (DC) cast Al-15.5Si-4Cu-1Mg-1Ni-0.5Cr alloy after solution treated at 500, 510, 520 and 530℃, respectively for different times. The major phases observed in the as-cast alloy are α-aluminum dendrite, primary Si p...

  12. Microstructure of Cast Ni-Cr-Al-C Alloy

    Directory of Open Access Journals (Sweden)

    Cios G.

    2015-04-01

    Full Text Available Nickel based alloys, especially nickel based superalloys have gained the advantage over other alloys in the field of high temperature applications, and thus become irreplaceable at high temperature creep and aggressive corrosion environments, such as jet engines and steam turbines. However, the wear resistance of these alloys is insufficient at high temperatures. This work describes a microstructure of a new cast alloy. The microstructure consists of γ matrix strengthened by γ’ fine precipitates (dendrites improving the high temperature strength and of Chromium Cr7C3 primary carbides (in interdendritic eutectics which are designed to improve wear resistance as well as the high temperature strength.

  13. Electrodeposition of magnesium and magnesium/aluminum alloys

    Science.gov (United States)

    Mayer, A.

    1988-01-21

    Electrolytes and plating solutions for use in processes for electroplating and electroforming pure magnesium and alloys of aluminum and magnesium and also electrodeposition processes. An electrolyte of this invention is comprised of an alkali metal fluoride or a quaternary ammonium halide, dimethyl magnesium and/or diethyl magnesium, and triethyl aluminum and/or triisobutyl aluminum. An electrolyte may be dissolved in an aromatic hydrocarbon solvent to form a plating solution. The proportions of the component compounds in the electrolyte are varied to produce essentially pure magnesium or magnesium/aluminum alloys having varying selected compositions.

  14. 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.

  15. Feeding and Distribution of Porosity in Cast Al-Si Alloys as Function of Alloy Composition and Modification

    DEFF Research Database (Denmark)

    Tiedje, Niels Skat; Taylor, John A.; Easton, Mark A.

    2012-01-01

    Unmodified, Na-modified, and Sr-modified castings of Al-7 pct Si and Al-12.5 pct Si alloys were cast in molds in which it was possible to create different cooling conditions. It is shown how solidification influences the distribution of porosity at the surface and the center of the castings as a...... casting, while Sr-modified castings solidify in a mushy manner that creates a more homogeneous distribution of porosity in the casting. The amount of porosity was highest in the Sr-modified alloys, lower in the Na-modified alloys, and lowest in the unmodified alloys. The size of the porosity-free layer...

  16. Friction Pull Plug Welding in Aluminum Alloys

    Science.gov (United States)

    Brooke, Shane A.; Bradford, Vann

    2012-01-01

    NASA's Marshall Space Flight Center (MSFC) has recently invested much time and effort into the process development of Friction Pull Plug Welding (FPPW). FPPW, is a welding process similar to Friction Push Plug Welding in that, there is a small rotating part (plug) being spun and simultaneously pulled (forged) into a larger part. These two processes differ, in that push plug welding requires an internal reaction support, while pull plug welding reacts to the load externally. FPPW was originally conceived as a post proof repair technique for the Space Shuttle fs External Tank. FPPW was easily selected as the primary weld process used to close out the termination hole on the Constellation Program's ARES I Upper Stage circumferential Self-Reacting Friction Stir Welds (SR-FSW). The versatility of FPPW allows it to also be used as a repair technique for both SR-FSW and Conventional Friction Stir Welds. To date, all MSFC led development has been concentrated on aluminum alloys (2195, 2219, and 2014). Much work has been done to fully understand and characterize the process's limitations. A heavy emphasis has been spent on plug design, to match the various weldland thicknesses and alloy combinations. This presentation will summarize these development efforts including weld parameter development, process control, parameter sensitivity studies, plug repair techniques, material properties including tensile, fracture and failure analysis.

  17. Predicting fatigue properties of cast aluminum by characterizing small-crack propagation behavior

    Science.gov (United States)

    Caton, Michael John

    2001-07-01

    The increased use of cast aluminum in structural components requires a deeper understanding of the mechanisms controlling fatigue properties in order to enable improved predictive capabilities. Of particular interest is the ability to model the influence of processing variables on the fatigue performance of alloys used in automotive applications such as engine blocks and cylinder heads. This thesis describes the results of a study conducted on cast W319 aluminum, a commercial Al-Si-Cu alloy used in automotive engine components, and presents a model that effectively predicts fatigue properties in this alloy as a function of material condition. The very high cycle fatigue regime (˜109 cycles) was examined using ultrasonic testing equipment (20 kHz) and distinct endurance limits were observed. The initiation and propagation of small fatigue cracks (˜5 mum to 2 mm) were monitored by a standard replication technique. It was observed that cracks initiate almost exclusively from microshrinkage pores and that the initiation life is negligible even at stresses below the endurance limit. The endurance limits result from the arrest of small cracks. Small crack growth rates were determined for a variety of material conditions where the influence of solidification time, heat treatment, and grain refinement were investigated. In addition, the influences of applied stress amplitude, stress ratio, and loading frequency on small crack growth were examined. A significant small crack effect was identified in this alloy and standard correlating parameters such as DeltaK and DeltaJ do not adequately characterize small crack growth. A correlating parameter written as [(epsilonmax sigmaa/sigma yield)s a] is proposed and shown to effectively characterize small crack growth for a wide range of stresses and a wide range of solidification conditions. In this parameter, epsilonmax is the total strain corresponding to the maximum applied stress, sigmaa is the stress amplitude, sigma yield is

  18. Kinetics of carbon distribution in uranium doping elements and its alloys at centrifugal casting

    International Nuclear Information System (INIS)

    The report presents results of the metallic Uranium and its Zirconium and Niobium alloys centrifugal cas-ting influence on the distribution mode of the alloying elements in casts,structure and carbide composition.Distribution mechanism of carbon and alloying elements in Uranium during centrifugal casting is suggested in the report

  19. Modification Mechanism of Rare Earth Elements in ZA27 Casting Alloys

    Institute of Scientific and Technical Information of China (English)

    刘贵立; 李荣德

    2003-01-01

    The model of the liquid-phase ZA27 alloys was set up by molecular dynamics theory. The atomic structure of phase, RE-compounds, and the phase-liquid interface in ZA27 alloys were constructed by computer programming. Electronic structures of phase with rare earth elements dissolved and of phase-liquid interfaces with rare earth elements enrichment in ZA27 casting alloys were investigated by using the Recursion method. The ESE energy of RE elements and the structure energy of RE-compounds, phase, and the liquid-phase ZA27 alloys were calculated. The results show that rare earth elements are more stable to be in the phase interface than in phase, which explains the fact of very small solid so lubility of rare earth elements in phase, and the enrichment in the solid-liquid growth front. This makes dendrite melt and break down, dissociate and propagate. RE-compounds can act as heterogeneous nuclei for phase, leading to phase refinement. All above elucidates the modification mechanism of rare earth elements in zinc-aluminum casting alloys at electronic level.

  20. Ceramic filters for bulk inoculation of nickel alloy castings

    OpenAIRE

    F. Binczyk; J. Śleziona; P. Gradoń

    2011-01-01

    The work includes the results of research on production technology of ceramic filters which, besides the traditional filtering function, playalso the role of an inoculant modifying the macrostructure of cast nickel alloys. To play this additional role, filters should demonstratesufficient compression strength and ensure proper flow rate of liquid alloy. The role of an inoculant is played by cobalt aluminateintroduced to the composition of external coating in an amount from 5 to 10 wt.% . The ...

  1. Mechanical properties and wear resistance of magnesium casting alloys

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2008-11-01

    Full Text Available Purpose: In the following paper there have been the properties of the MCMgAl12Zn1, MCMgAl9Zn1, MCMgAl6Zn1, MCMgAl3Zn1magnesium cast alloy as-cast state and after a heat treatment presented.Design/methodology/approach: A casting cycle of alloys has been carried out in an induction crucible furnace using a protective salt bath Flux 12 equipped with two ceramic filters at the melting temperature of 750±10ºC, suitable for the manufactured material. The following results concern abrasive wear, mechanical properties, light and scanning microscopy.Findings: The different heat treatment kinds employed contributed to the improvement of mechanical properties of the alloy with the slight reduction of its plastic properties.Research limitations/implications: According to the alloys characteristic, the applied cooling rate and alloy additions seems to be a good compromise for mechanical properties and microstructures, nevertheless further tests should be carried out in order to examine different cooling rates and parameters of solution treatment process and aging process.Practical implications: The concrete examples of the employment of castings from magnesium alloys in the automotive industry are elements of the pedals, dashboards, elements of seats, steering wheels, wheel bands, oil sumps, elements and housings of the gearbox, framing of doors and sunroofs, and others, etc.Originality/value: Contemporary materials should possess high mechanical properties, physical and chemical, as well as technological ones, to ensure long and reliable use. The above mentioned requirements and expectations regarding the contemporary materials are met by the non-ferrous metals alloys used nowadays, including the magnesium alloys.

  2. RESEARCH OF INFLUENCE OF LIQUID ALUMINUM ON RESISTANCE OF THE STEEL AND CAST-IRON TOOL

    OpenAIRE

    S. S. Zhizhchenko; I. A. Shpareva; M. A. Turchanin; P. G. Agraval

    2015-01-01

    The study of the interaction of steel and cast iron with aluminum was performed by immersion, and isothermal holding. By optical and electron microscopy, the microstructure of the reaction zone was investigated. The partial enthalpy of dissolution of iron, steel and cast iron in liquid aluminum has been investigated by high-temperature calorimetry at 1773 K. X-ray analysis and microhardness measurements was used to study the phase composition of the reaction zone. The thermodynamic descriptio...

  3. Measurement of Thermodynamic Properties of Titanium Aluminum Alloys

    Science.gov (United States)

    Mehrotra, Gopal

    1995-01-01

    This final report is a summary of the work done by Professor Mehrotra at NASA Lewis Research Center. He has worked extensively on the measurement of thermodynamic properties of titanium aluminum alloys over the past six years.

  4. The development of recycle-friendly automotive aluminum alloys

    Science.gov (United States)

    Das, Subodh K.; Green, J. A. S.; Kaufman, J. Gilbert

    2007-11-01

    The continuing growth of aluminum alloy usage in transportation applications, notably passenger automobiles and minivans, and the demonstrated economic benefits of recycling aluminum-rich vehicles increase the need to seriously consider the desirability of designing recycling-friendly alloys. This article focuses on that aspect of the recycling process for passenger vehicles. The goals are to illustrate the opportunities afforded by identifying and taking full advantage of potential metal streams in guiding the development of new alloys that use those streams. In speculating on several possible aluminum recovery practices and systems that might be used in recycling passenger vehicles, likely compositions are identified and preliminary assessments of their usefulness for direct recycling are made. Specific compositions for possible new recycle-friendly alloys are suggested. In addition, recommendations on how the aluminum enterprise, including industry, academia, and government, can work together to achieve the aggressive but important goals described here are discussed.

  5. Paint-Bonding Improvement for 2219 Aluminum Alloy

    Science.gov (United States)

    Daech, Alfred F.; Cibula, Audrey Y.

    1987-01-01

    Bonding of adhesives and primers to 2219 aluminum alloy improved by delaying rinse step in surface-treatment process. Delaying rinse allows formation of rougher surface for stronger bonding and greater oxide buildup.

  6. Comparison of the texture evolution in cold rolled DC and SC AA 5182 aluminum alloys

    International Nuclear Information System (INIS)

    The hot bands of direct chill cast (DC) and strip cast (SC) AA 5182 aluminum alloys were annealed at 454 deg. C for 3 h, and then cold rolled to different reductions. The ODFs of the cold rolled samples were determined by X-ray diffraction in order to compare the texture evolution of DC and SC AA 5182 aluminum alloys during rolling. The texture volume fractions were computed by a new method, in which the Euler space representing all possible crystallographic orientations in rolling was subdivided into the cube, r-cube, Goss, r-Goss, β fiber, and random orientation regions based on the slip pattern combined with the characteristics of microstructure and texture. Empirical formulae of the texture volume fractions and true strain were constructed to predict the texture of cold rolled DC and SC AA 5182 aluminum alloys. The results show that the processing method (DC vs. SC) strongly affects the texture after annealing at 454 deg. C and the texture evolution during the subsequent rolling

  7. Development of manufacturing process of wrought magnesium alloy sheets by twin roll casting

    Directory of Open Access Journals (Sweden)

    H. Watari

    2007-01-01

    Full Text Available Purpose: The purpose of the work is to development of a strip casting technology for manufacturing magnesiumalloy sheets. The aim of the work is to establish a manufacturing process and technology to facilitate theeconomical manufacture of high-strength magnesium sheet alloys.Design/methodology/approach: A horizontal type twin roll caster was used to manufacture magnesium alloysheets. Pair of copper alloy roll, pure copper roll and steel roll was used for the horizontal type twin roll caster.The diameter of the rolls was 300mm and the width of rolls was 100 and 150mm.Findings: The magnesium alloy sheets could be succcessfully manufactured by the horizontal twin roll caster. Theproduct sheet thickness in the present experiment was 2.0 to 5.0mm. The equiaxed microstrucure was observed incast magnesium alloys when a pair of copper and cupper aolly rolls were used. The mean grain size of the castmagnesium alloys strip was from 30 to 60 micrometers. After hot rolling process, the grain size was reduced to about10 micrometers. The obtained magnesium alloy sheet indicated a good plastic formability by a warm-drawing test.Research limitations/implications: The superheat in the experiment was between 15ºC and 30ºC, also anappropriate hot rolling temperature was 250ºC for AZ31, AZ61 and AM60, 300ºC for AZ91.Practical implications: The proposed manufacturing process was effective from the view point of economicalmanufacturing process as well as of formation of rapid solidification microstructures. Introducing the twin rollcasting technology enable to manufacture magnesium sheet alloys with high aluminum contents, such as AZ61,AM60 and AZ91.Originality/value: AZ31, AM60, AZ61 and AZ91 wrought magnesium alloy sheets can be manufacturedeconomically by twin roll casting. These cast sheet can be hot rolled and the proposed manufacturing processenables manufacturer to manufacure thin magnesium alloy sheets with high aluminum contents such as AM60,AZ61 and AZ

  8. Microstructure And Mechanical Properties Of An Al-Zn-Mg-Cu Alloy Produced By Gravity Casting Process

    Directory of Open Access Journals (Sweden)

    Saikawa S.

    2015-06-01

    Full Text Available High-strength aluminum alloy are widely used for structural components in aerospace, transportation and racing car applications. The objective of this study is to enhance the strength of the Al-Zn-Mg-Cu alloy used for gravity casting process. All alloys cast into stepped-form sand mold (Sand-mold Casting; SC and Y-block shaped metal mold(Permanent mold Casting; PC C and then two –step aged at 398-423 K after solution treated at 743 K for 36 ks. The tensile strength and total elongation of the two-step aged SC alloys were 353-387 MPa and about 0.4% respectively. This low tensile properties of the SC alloys might be caused by remaining of undissolved crystallized phase such as Al2CuM, MgZn2 and Al-Fe-Cu system compounds. However, good tensile properties were obtained from PC alloys, tensile strength and 0.2% proof stress and elongation were 503-537 MPa, 474-519 MPa and 1.3-3.3%.

  9. Geometrical product specifications heat-resistant cobalt cast alloy

    Directory of Open Access Journals (Sweden)

    Lyubimov V.

    2007-01-01

    Full Text Available Geometrical product specification MAR-M509 cast cobalt alloy depend beginning temperature of multilayer ceramic shell moulds (MCS. It has found that go down temperature of MCS from 1000°C to 200°C, the increase surface roughness and its amplitude parameters: Sa, Sz, St, Sq, Sp and Sv.

  10. Geometrical product specifications heat-resistant cobalt cast alloy

    OpenAIRE

    Lyubimov V.; Opiekun Z.; Bonk C.

    2007-01-01

    Geometrical product specification MAR-M509 cast cobalt alloy depend beginning temperature of multilayer ceramic shell moulds (MCS). It has found that go down temperature of MCS from 1000°C to 200°C, the increase surface roughness and its amplitude parameters: Sa, Sz, St, Sq, Sp and Sv.

  11. Comparison of thermodynamic databases for 3xx and 6xxx aluminum alloys

    Science.gov (United States)

    Ravi, C.; Wolverton, C.

    2005-08-01

    Computational thermodynamics, or Calculation of Phase Diagram (CALPHAD) methods have proven useful in applications to modeling a variety of alloy properties. However, the methods are only as accurate as the thermodynamic databases they use, and two commercial thermodynamic databases exist for aluminum alloys: Thermotech and Computherm. In order to provide a critical comparison of these databases, we used both the databases to calculate equilibrium solid-state phase fractions and phase diagram isothermal sections of several industrial aluminum alloys: a 319-type and 356 cast alloys, as well as the wrought alloys 6022 and 6111. All of these alloys may be generically described as being based on the Al-Mg-Si-Cu quaternary with other additions such as Fe, Mn, and Zn. Although many of the results are consistent between the two databases, several qualitative and quantitative differences were observed. Many of these differences are found to be due to the intermetallic compounds involving Fe, Mn, Cr, and Zn. On the other hand, thermodynamics involving only phases from the Al-Mg-Si-Cu quaternary show good agreement between the databases, although some small differences still exist, particularly involving the quaternary Q phase. To understand and assess these differences, formation enthalpies and reaction energies from the databases were compared against density functional first-principles energetics. These comparisons indicate possible avenues for future improvements of Al-alloy thermodynamic databases. Finally, we demonstrate an interesting correlation between the calculated phase fractions and the measured yield strengths across this wide family of 3xx cast and 6xxx wrought alloys.

  12. [Casting of dental alloys with special reference to the bonding capacity of Ni-Cr alloys].

    Science.gov (United States)

    Weber, H

    1979-07-01

    A short review on castability of dental alloys -- for which a definition is proposed -- reflects the different factors influencing the results of a casting. In this case solid sieves and plates are cast by use of one gold-base alloy (Type III) and two base metal alloys used for porcelain veneering. All three alloys filled the sieve pattern to a 100%, whereas they performed differently when cast as thin, solid squares. The most continuous results were achieved with a Ni-Cr-alloy whose melting temperature can be recognized since the ingots flow together when this point is reached. Since the plate pattern is most difficult to cast due to surface to bulk ratio it is assumed that a complete casting can only be achieved when the performance of the alloy is good and all required conditions match. Thus, this type of test seems to be suitable to determine the castability of a dental alloy. The sieve test should be used to investigate and to improve the influence of the different factors as for example burnout time and temperature of the mold and sprue size. PMID:380961

  13. The intermetallic bonding between a ring carrier and aluminum piston alloy

    International Nuclear Information System (INIS)

    This paper presents the results of investigating the formation of intermetallic bond between a ring carrier and aluminum piston alloy. The ring carrier is made of austenitic cast iron (Ni-Resist) in order to increase the wear resistance of the first ring groove and applied in highly loaded diesel engines. Metallographic examination of the quality of al fin bond was done. A metallographic investigation using an optical microscope in combination with the SEM/EDS analysis of the quality of the intermetallic bonding layer was done. The test results show that can be made successfully as well as the formation of metal connection (alfin bond) between the ring carrier and aluminum piston alloy. (Author)

  14. The intermetallic bonding between a ring carrier and aluminum piston alloy

    Energy Technology Data Exchange (ETDEWEB)

    Manasijevie, S.; Dolie, N.; Djurdjevic, M.; Misic, N.; Davitkov, N.

    2015-07-01

    This paper presents the results of investigating the formation of intermetallic bond between a ring carrier and aluminum piston alloy. The ring carrier is made of austenitic cast iron (Ni-Resist) in order to increase the wear resistance of the first ring groove and applied in highly loaded diesel engines. Metallographic examination of the quality of al fin bond was done. A metallographic investigation using an optical microscope in combination with the SEM/EDS analysis of the quality of the intermetallic bonding layer was done. The test results show that can be made successfully as well as the formation of metal connection (alfin bond) between the ring carrier and aluminum piston alloy. (Author)

  15. STABILITY OF THE FAST-QUENCHED ALUMINUM ALLOYS MICROSTRUCTURE

    OpenAIRE

    A. S. Kalinichenko; V. A. Kalinichenko; V. S. Niss; S. V. Grigoryev

    2015-01-01

    The conducted researches of continuous stability of microstructures of the fast-quenched tapes from alloys of aluminum and chrome showed that the natural aging accompanied by discharge of stable phases is observed in copper-bearing alloys. There are no changes in microstructure in the chrome-bearing fast-chilled tapes that confirms their high temporary stability.

  16. Cooling Rate Determination in Additively Manufactured Aluminum Alloy 2219

    Science.gov (United States)

    Brice, Craig A.; Dennis, Noah

    2015-05-01

    Metallic additive manufacturing processes generally utilize a conduction mode, welding-type approach to create beads of deposited material that can be arranged into a three-dimensional structure. As with welding, the cooling rates in the molten pool are relatively rapid compared to traditional casting techniques. Determination of the cooling rate in the molten pool is critical for predicting the solidified microstructure and resultant properties. In this experiment, wire-fed electron beam additive manufacturing was used to melt aluminum alloy 2219 under different thermal boundary conditions. The dendrite arm spacing was measured in the remelted material, and this information was used to estimate cooling rates in the molten pool based on established empirical relationships. The results showed that the thermal boundary conditions have a significant effect on the resulting cooling rate in the molten pool. When thermal conduction is limited due to a small thermal sink, the dendrite arm spacing varies between 15 and 35 µm. When thermal conduction is active, the dendrite arm spacing varies between 6 and 12 µm. This range of dendrite arm spacing implies cooling rates ranging from 5 to 350 K/s. Cooling rates can vary greatly as thermal conditions change during deposition. A cooling rate at the higher end of the range could lead to significant deviation from microstructural equilibrium during solidification.

  17. MICROSTRUCTURE ANALYSIS AND MECHANICAL PROPERTIES OF Zn-Al ALLOY ROD PRODUCED BY HEATED MOLD CONTINUOUS CASTING

    Institute of Scientific and Technical Information of China (English)

    Y. Ma; Y. Hao; F.Y. Yan; H.J.Liu

    2003-01-01

    The new technology of continuous casting by heated mold was used to produce dtirectional solidification ZA alloy lines to eliminate the inter defects of these lines and increase their mechanical properties. The results are as follows: (1) The microstructure of the ZA alloy lines is the parallel directional dendritic columnar crystal. Every dendritic crystal of eutectic alloy ZA5 was composed of many layer eutectic β and η phases. The microstructure of hypereutectic ZA alloys is primary dendritic crystal and interdendritic eutectic structure. The primary phase of ZA8 and ZA12 isβ,among them, but the primary phase of ZA22 and ZA27 is α. (2) Through the test to the as-cast ZA alloy lines made in continuous casting by heated mold, it is found that the tensile strength and hardness increase greatly, but the elongation decreases. With the increase of aluminum amount from ZA 5 to ZA 12, ZA22 and ZA27, the tensile strength increases gradually. ZA27 has the best comprehensive mechanical properties in these four kinds of ZA alloys. (3) Heat treatment can decrease the dendritic segregation and improve the elongation of ZA alloy, but make their strength decrease slightly.

  18. Modification of Magnesium Alloys by Ceramic Particles in Gravity Die Casting

    Directory of Open Access Journals (Sweden)

    Urs Haßlinger

    2014-01-01

    Full Text Available A critical drawback for the application of magnesium wrought alloys is the limited formability of semifinished products that arises from a strong texture formation during thermomechanical treatment. The ability of second phase particles embedded into the metal matrix to alter this texture evolution is of great interest. Therefore, the fabrication of particle modified magnesium alloys (particle content 0.5–1 wt.-% by gravity die casting has been studied. Five different types of micron sized ceramic powders (AlN, MgB2, MgO, SiC, and ZrB2 have been investigated to identify applicable particles for the modification. Agglomeration of the particles is revealed to be the central problem for the fabrication process. The main factors that influence the agglomerate size are the particle size and the intensity of melt stirring. Concerning handling, chemical stability in the Mg-Al-Zn alloy system, settling and wetting in the melt, and formation of the microstructure in most cases, the investigated powders show satisfying properties. However, SiC is chemically unstable in aluminum containing alloys. The high density of ZrB2 causes large particles to settle subsequent to stirring resulting in an inhomogeneous distribution of the particles over the cast billet.

  19. 3D scanning based mold correction for planar and cylindrical parts in aluminum die casting

    Directory of Open Access Journals (Sweden)

    Takashi Seno

    2015-04-01

    Full Text Available Aluminum die casting is an important manufacturing process for mechanical components. Die casting is known to be more accurate than other types of casting; however, post-machining is usually necessary to achieve the required accuracy. The goal of this investigation is to develop machining- free aluminum die casting. Improvement of the accuracy of planar and cylindrical parts is expected by correcting metal molds. In the proposed method, the shape of cast aluminum made with the initial metal molds is measured by 3D scanning. The 3D scan data includes information about deformations that occur during casting. Therefore, it is possible to estimate the deformation and correction amounts by comparing 3D scan data with product computer-aided design (CAD data. We corrected planar and cylindrical parts of the CAD data for the mold. In addition, we corrected the planar part of the metal mold using the corrected mold data. The effectiveness of the proposed method is demonstrated by evaluating the accuracy improvement of the cast aluminum made with the corrected mold.

  20. Age hardening in beryllium-aluminum-silver alloys

    International Nuclear Information System (INIS)

    Three different alloys of beryllium-aluminum-silver were processed to powder by centrifugal atomization in a helium atmosphere. Alloy compositions were, by weight percent, Be-47.5Al-2.5Ag, Be-47Al-3Ag, and Be-46Al-4Ag. Due to the low solubility of both aluminum and silver in beryllium, the silver was concentrated in the aluminum phase, which separates from the beryllium in the liquid phase. A fine, continuous composite beryllium-aluminum microstructure was formed, which did not significantly change after hot isostatic pressing. Samples of hot isostatically pressed material were solution treated at 550 C for 1 h, followed by a water quench. Aging temperatures were 150, 175, 200, and 225 C for times ranging from half an hour to 65 h. Results indicate that peak hardness was reached in 36--40 h at 175 C and 12--16 h at 200 C aging temperature, relatively independent of alloy composition

  1. Multi-wall carbon nanotubes reinforced aluminum composites synthesized by hot press sintering and squeeze casting

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-xi; YANG Li; DENG Chun-feng; WANG De-zun

    2006-01-01

    Multi-wall carbon nanotubes (MWNTs) have high mechanical properties and are considered a kind of realistic reinforcement for polymers, ceramics and metals. The hot press sintering and squeeze casting were adopted to synthesize MWNTs reinforced aluminum composites. In hot press sintered MWNTs/Al composites, MWNTs agglomerates distribute along aluminum powders and have low bonding strength with aluminum. But MWNTs agglomerates distribute evenlyin the squeeze cast MWNTs/Al composites. Some dispersed nanotubes bond well with aluminum matrix and few dislocations can be found in the nanotube areas,which implies little thermal residual stress in squeeze cast MWNTs/Al composites. This indicates that the strengthen mechanisms in nanometer sized MWNTs/Al composites may be different from that in micrometer sized whisker composites.

  2. Controlled Directional Solidification of Aluminum - 7 wt Percent Silicon Alloys: Comparison Between Samples Processed on Earth and in the Microgravity Environment Aboard the International Space Station

    Science.gov (United States)

    Grugel, Richard N.; Tewari, Surendra N.; Erdman, Robert G.; Poirier, David R.

    2012-01-01

    An overview of the international "MIcrostructure Formation in CASTing of Technical Alloys" (MICAST) program is given. Directional solidification processing of metals and alloys is described, and why experiments conducted in the microgravity environment aboard the International Space Station (ISS) are expected to promote our understanding of this commercially relevant practice. Microstructural differences observed when comparing the aluminum - 7 wt% silicon alloys directionally solidified on Earth to those aboard the ISS are presented and discussed.

  3. Microstructure 2007of WE43 casting magnesium alloy

    Directory of Open Access Journals (Sweden)

    A. Kiełbus

    2007-03-01

    Full Text Available Purpose: WE43 is a high-strength magnesium alloy characterized by good mechanical properties both at an ambient and elevated temperature (up to 300°C. It contains mainly yttrium and neodymium. The aim of this paper is to present the results of research on the microstructure of the WE43 magnesium alloy in an as-cast condition.Design/methodology/approach: For the microstructure observation, a Reichert metallographic microscope MeF2 and a HITACHI S-3400N scanning electron microscope with a Thermo Noran EDS equipped with SYSTEM SIX were used. A qualitative phase analysis was performed with a JEOL JDX-7S diffractometer. Microstrucutral examinations were performed JEOL 3010 transmission electron microscope.Findings: Based on the investigation carried out it was found that the microstructure of WE43 alloy after continuous casting consists of α-Mg matrix and irregular precipitates of Mg41Nd5, rectangular particles of MgY phase, particles of Mg24Y5, longitudinal precipitates of β (Mg14Nd2Y compound at grain boundaries and the grain interiors. All of these phases contain yttrium and neodymium. Research limitations/implications: Future researches should contain investigations of the influence of heat treatment parameters on microstructure, corrosion resistance and mechanical properties of WE43 alloy.Practical implications: WE43 magnesium alloy is used in the aircraft industry, for wheels, engine casings, gear box casings and rotor heads in helicopters. Results of investigation may be useful for development casting technology of the Mg-Y-Nd alloys.Originality/value: The results of the researches make up a basis for the next investigations of magnesium alloys with addition of Y and Nd designed to exploitation at temperature to 300°C.

  4. Thermodynamic Modeling as a Strategy for Casting High Alloy Steels

    Institute of Scientific and Technical Information of China (English)

    Peri Reddy V; S Raman Sankaranarayanan

    2009-01-01

    Strategies based on thermodynamic calculations can be used to overcome the problems associated with oxides encountered in steel plant operations, which can lead to certain difficulties in the process such as clogging of submerged entry nozzle during continuous casting. Approaches to producing high alloy steels by continuous casting have been taken. One of the strategies to avoid the oxidation of chromium is to add a small amount of other elements (subject to other constraints), which do not cause subsequent problems. The problem has been studied using the Thermo-CalcR software, with related databases; and the results obtained for different process conditions or generic com-positions have been presented.

  5. In vivo effects of dental casting alloys

    Czech Academy of Sciences Publication Activity Database

    Venclíková, Z.; Benada, Oldřich; Bártová, J.; Joska, L.; Mrklas, L.; Procházková, J.; Stejskal, V.D.M.; Podzimek, Š.

    2006-01-01

    Roč. 27, č. 1 (2006), s. 25-32. ISSN 0172-780X R&D Projects: GA MZd NK7437 Institutional research plan: CEZ:AV0Z50200510 Keywords : dental alloys * metals * gingiva Subject RIV: EE - Microbiology, Virology Impact factor: 0.924, year: 2006

  6. Structure changes and mechanical properties of laser alloyed magnesium cast alloys

    Directory of Open Access Journals (Sweden)

    W. Kwaśny

    2009-02-01

    Full Text Available Purpose: The aim of this work was to investigate structure and mechanical properties of the MCMgAl12Zn1 casting magnesium alloys after laser treatment. The laser treatment was carried out using a high power diode laser (HPDL.Design/methodology/approach: The laser processing of TiC, WC, SiC particles in MCMgAl12Zn1 and the resulted microstructures and properties are discussed in this paper. The resulting microstructure in the modified surface layer was examined. Phase composition was determined by the X-ray diffraction method using XPert device. The measurements of hardness after laser melt injection was also studied.Findings: Structure of the solidyifying material after laser alloying is characteristic with occurrences of areas with the diversified morphology, dependent on solidification rate of the magnesium alloys, is characteristic of structure of the solidified material after laser alloying. The MCMgAl12Zn1 casting magnesium alloys after laser alloying demonstrate similar hardness tests results, in reference to hardness of the alloys before their laser treatment.Research limitations/implications: In this research three powders (titanium carbide, tungsten carbide and silicon carbide were used to reinforcing the surface of the MCMgAl12Zn1 casting magnesium alloys.Practical implications: High power diode laser can be used as an economical substitute for CO2 and Nd:YAG lasers to modify the surface magnesium alloy by feeding the carbide particles.Originality/value: The originality of this work is applying of High Power Diode Laser for laser treatment of cast magnesium alloy consisting in fusion penetration of the hard particles of titanium, tungsten, and silicon carbides into the remelted surface layer of the alloy.

  7. Effects of erbium modification on the microstructure and mechanical properties of A356 aluminum alloys

    International Nuclear Information System (INIS)

    The effects of erbium (Er) modification on the microstructure and mechanical properties of A356 aluminum alloys were investigated using optical microscope, X-ray diffraction, scanning electronic microscope and mechanical testing. Experimental results show that additions of Er refined the α-Al grains and eutectic Si phases in its as-cast state; the addition of 0.3 wt% of Er has the best effects on them. The Fe-containing Al3Er phases were introduced by the modifications; by a T6 treatment, the eutectic Si phases were further sphereodized; the large Al3Er and β-Al5FeSi phases were changed into fine particles and short rods; which enhanced the hardness of the alloys. The highest strength and elongation were obtained for the 0.3 wt% of Er-modified and T6-treated A356 alloy

  8. The Stand of Horizontal Continuous Casting of Al and its Alloys

    Directory of Open Access Journals (Sweden)

    T. Wróbel

    2013-07-01

    Full Text Available In paper is presented idea of construction and influence of selected parts of stand of horizontal continuous casting on quality of pure Al and AlSi2 alloy ingots. The main parts of the made stand belong to induction furnace, which is also tundish, water cooled continuous casting mould, system of recooling, system of continuous ingot drawing and cutting. Mainly was considered influence of electromagnetic stirrer, which was placed in continuous casting mould on refinement of ingots structure. Effect of structure refinement obtained by influence of electromagnetic stirring was compared with refinement obtained by use of traditional inoculation, which consists in introducing of additives i.e. Ti and B to metal bath. The results of studies show possibility of effective refinement of Al and AlSi2 alloy primary structure, only with use of horizontal electromagnetic field and without necessity of application of inoculants. This method of inoculation is important, because inoculants decrease the degree of purity and electrical conductivity of pure aluminum and moreover are reason of point cracks formation during rolling of ingots.

  9. High speed roll casting of Mg alloy strip by a vertical type twin roll caster

    Directory of Open Access Journals (Sweden)

    H. Watari

    2006-02-01

    Full Text Available Purpose: The possibility of high speed roll casting of AZ31, AM60 and AZ91 was investigated. Warm deep drawing of roll cast magnesium alloy was operated. and formability of roll cast magnesium strip was cleared.Design/methodology/approach: A vertical type high speed twin roll caster was used. The roll casting was operated in the air atmosphere. The casting speed was from 60 m/min up to 180 m/min. Low temperature casting was adopted to realize high speed casting.Findings: Strip thinner 3 mm with 100 width could be cast continuously. The casting ability became better with increasing content of Al. Roll cast Mg alloy strips could be hot-rolled down to 0.5 mm. AZ31 as-cast strip could be thinner down to 0.5 mm only by three times of hot rolling. Deep drawing was operated with three kinds of Mg alloy at 250°C, and LDR value was larger than 2.0. It was shown that deep drawing of AZ91 alloy for casting was possible.Research limitations/implications: There was tendency that cracks occurred at the center in the thickness direction as Al content increased.Practical implications: Sheet metal forming of magnesium alloy with high content Al can be realized.Originality/value: It was shown that possibility of high speed roll casting of magnesium alloy, and warm deep drawing of roll cast AZ91 strip.

  10. Thermoelectrical power analysis of precipitation in 6013 aluminum alloy

    International Nuclear Information System (INIS)

    The 6013 aluminum alloy was first developed for application in the aircraft industry and, more recently, as a replacement option for the use of the 6061 alloy in the automotive industry. The present work describes the evolution of the process of formation and dissolution of different kinds of precipitates in 6013 aluminum alloy, subjected to different conditions of heat treatment, using for this purpose measurements of thermoelectrical power, Vickers microhardness and differential scanning calorimeter (DSC). Although in the last years many works have been published on the use of thermoelectrical power (TEP) measurements for the analysis of precipitation process in traditional alloys such as 6061, there is still little information related to 6013 alloy. The results obtained are compared with a previous characterization work on the same alloy using transmission electron microscopy. It was observed that TEP measurements are very sensitive to precipitation phenomena in this alloy, and it has been found that there is an inverse relation between TEP and Vickers microhardness values, which allowed proposing a precipitation sequence for 6013 aluminum alloy

  11. Laser surface treatment of cast Al-Si-Cu alloys

    OpenAIRE

    K. Labisz

    2013-01-01

    Purpose: The test results presented in this chapter concern formation of the quasi-composite MMCs structure on the surface of elements from aluminium cast alloys AC-AlSi9Cu and AC-AlSi9Cu4 by fusion of the carbide or ceramic particles WC, SiC, ZrO2 and Al2O3 in the surface of alloys. In addition, within the scope of the tests the phase transformations and precipitation processes present during laser remelting and fusion at appropriately selected parameters: laser power, the ra...

  12. Laser surface treatment of cast Al-Si-Cu alloys

    Directory of Open Access Journals (Sweden)

    K. Labisz

    2013-12-01

    Full Text Available Purpose: The test results presented in this chapter concern formation of the quasi-composite MMCs structure on the surface of elements from aluminium cast alloys AC-AlSi9Cu and AC-AlSi9Cu4 by fusion of the carbide or ceramic particles WC, SiC, ZrO2 and Al2O3 in the surface of alloys. In addition, within the scope of the tests the phase transformations and precipitation processes present during laser remelting and fusion at appropriately selected parameters: laser power, the rate of fusion and quantity of the ceramic powder fed have been partially examined. Design/methodology/approach: In general, the laser surface processing should result in achievement of the surface layer with the most favourable physical and mechanical properties, in particular enhancement of surface hardness, improvement of abrasion resistance and resistance to corrosion is assumed in relation to the selected aluminium alloys after standard thermal processing. Findings: The presented results of the surface layer include analysis of the mechanisms responsible for formation of the layer, and particularly concern remelting of the substrate and its crystallisation at various parameters of the High Power Diode Laser (HPDL and the technological conditions of the surface processing, remelting and fusion of the particles in the surface of cast alloys ACAlSi9Cu and ACAlSi9Cu4. For the purpose of testing the structure of the obtained surface layers the test methods making use of the light microscopy method supported with computer image analysis, transmission and scanning electron microscopy, X-ray analysis, X-ray microanalysis, as well as methods for testing the mechanical and usable properties have been used. Practical implications: What is more, development of the technology of surface refinement of cast alloys Al-Si-Cu with the laser fusion methods will allow for complex solving of the problem related to enhancement of the surface layer properties, taking into account both economic

  13. The NBS: Processing/Microstructure/Property Relationships in 2024 Aluminum Alloy Plates

    Science.gov (United States)

    Ives, L. K.; Swartzendruber, W. J.; Boettinger, W. J.; Rosen, M.; Ridder, S. D.

    1983-01-01

    As received plates of 2024 aluminum alloy were examined. Topics covered include: solidification segregation studies; microsegregation and macrosegregation in laboratory and commercially cast ingots; C-curves and nondestructive evaluation; time-temperature precipitation diagrams and the relationships between mechanical properties and NDE measurements; transmission electron microscopy studies; the relationship between microstructure and properties; ultrasonic characterization; eddy-current conductivity characterization; the study of aging process by means of dynamic eddy current measurements; and Heat flow-property predictions, property degradations due to improve quench from the solution heat treatment temperature.

  14. Microstructural characterization of as-cast Co-Si alloys

    International Nuclear Information System (INIS)

    This work presents results of microstructural characterization of as-cast Co-Si alloys. The alloys of different compositions were prepared by arc melting Co (min. 99.97%) and Si (min. 99.99%) under argon atmosphere in a water-cooled copper crucible with a nonconsumable tungsten electrode and titanium getter. All samples were characterized by scanning electron microscopy (SEM) using back-scattered electron (BSE) mode and X-ray diffraction (XRD). A good conformity between the currently accepted Co-Si phase diagram and the experimental results from this work was verified. No indication of the βCo2Si was observed in the as-cast microstructures. As in previous investigations, the Co3Si phase has not been observed in the samples at room temperature; however, microstructural evidence suggests its stability at high temperature

  15. Description Of Alloy Layer Formation On A Cast Steel Substrate

    Directory of Open Access Journals (Sweden)

    Szajnar J.

    2015-09-01

    Full Text Available A description of alloy layer formation on a steel substrate is presented. Two types of formation are considered: diffusion of carbon and chromium into the solid from the pad in the direction of the cast steel within the FeCrC (grains and diffusion in a layer of liquid chromium cast iron formed in a preceding step. The influence of silicon in the pad on the pad’s transformation into the liquid is also examined. Solidus and liquidus temperatures of high carbon ferrochromium are determined. The larger the content of Si is used in the experiment, the lower the solidus temperature of the FeCrC alloy is observed. This results from the higher intensity of the elements’ diffusion and faster formation of the liquid.

  16. Replication of specifically microstructured surfaces in A356-alloy via lost wax investment casting

    International Nuclear Information System (INIS)

    A common way of realizing microstructural features on metallic surfaces is to generate the designated pattern on each single part by means of microstructuring technologies such as e.g. laser ablation, electric discharge machining or micromilling. The disadvantage of these process chains is the limited productivity due to the additional processing of each part. The approach of this work is to replicate microstructured surfaces from a master pattern via lost wax investment casting in order to reach a higher productivity. We show that microholes of different sizes ( 15–22 µm at depths of 6–14 µm) can be replicated in AlSi7Mg-alloy from a laser-structured master pattern via investment casting. However, some loss of molding accuracy during the multi-stage molding process occurs. Approximately 50% of the original microfeature's heights are lost during the wax injection step. In the following process step of manufacturing a gypsum-bonded mold, a further loss in the surface quality of the microfeatures can be observed. In the final process step of casting the aluminum melt, the microfeatures are filled without any loss of molding accuracy and replicate the surface quality of the gypsum mold. The contact angle measurements of ultrapure water on the cast surfaces show a decrease in wettability on the microstructured regions (75°) compared to the unstructured region (60°)

  17. Study of morphology of oxide film formed on magnesium alloys in casting conditions (AZ91)

    International Nuclear Information System (INIS)

    Morphology of surface oxide film formed during pouring of molten magnesium alloy has been investigated. Due to surface turbulence during casting, the oxide film necessarily makes folded cause in a dry surface to dry surface mode creating a double oxide film with the volume of air that can be encapsulated between folds of the film and this led to make gas bubbles or shrinkage cavities form. These kinds of oxides called new oxide films that form in a very short time during pouring. It seems to be one of the main reasons for dross-like defects. However, study of characterization and features of oxide film affected on prediction of final mechanical properties. The inner, un wetted surfaces of the doubled film representing an unbounded interface in the liquid and therefore, effectively constitute a crack. Samples for the study were prepared based on a technique in which an oxide metal sandwich was made by the bubble impingement technique, after impingement the contact areas of two adjacent and entrapped bubbles oxide-metal-oxide layer were selected for the study. Features such as thickness, size, morphology and chemical composition of the oxide film were studied using a scanning electron microscope. Energy dispersive X-ray microanalysis was performed for detection of the composition of the oxide layers. Results showed that the morphology of the oxide film in molten of magnesium alloys is folded and quite rough included globally phases of magnesium oxide. Recently, researches showed that the morphology of the oxide film in aluminum alloys is different due to composition of base alloy. Magnesium alloys in liquid state due to high oxidation rate is sensitive to formation of oxide film. Thickness of the oxide film folds in magnesium alloys is 2-4 μm that in comparison to aluminum alloys are ten times higher. However, potential of casting defects is higher in Mg alloys. The contacting interface between impinged bubbles represents an elegant and powerful means for studying

  18. Joint properties of friction welded 6061 aluminum alloy/YSZ–alumina composite at low rotational speed

    International Nuclear Information System (INIS)

    Highlights: • Joint properties of FW for 6061 Al alloy/alumina–YSZ composite were clarified. • Different technique analyses with varying speeds were used in the experiment. • The microstructure, microhardness and bending strength of the joint were evaluated. • The results showed that joint was able to be friction welded in the low speed. • The low speed gave maximum bending strength and lower microhardness values. - Abstract: In this study, a ceramic composite of alumina–yttria stabilized zirconia (YSZ) was friction welded to 6061 aluminum alloy. Alumina rods containing 25 wt.% YSZ were formed using slip casting and subsequently sintered at 1600 °C to form a solid body. The 6061 aluminum alloy sample was cut and polished, and then subjected to friction welding experiments. Both rods were 16 mm in diameter. The results of this study showed that the alumina–25 wt.% YSZ composite was able to be friction welded to 6061 aluminum alloy at a lower rotational speed of 630 rpm compared with high rotational speeds. The friction force was maintained at 5 KN for a frictional time of 30 s. Optical Microscopy (OM) and Field Emission Scanning Electron Microscope (FESEM) were used to analyze the microstructure of the products, particularly at the interface of the joints. The joints were also examined with EDX line and area (energy dispersive X-ray) in order to determine the phases formed during the low speed welding. The mechanical properties including bending strength and Vickers microhardness were measured. The experimental results indicated that the mechanical strength of friction welded alumina–25 wt.% YSZ composite/6061 aluminum alloy components were obviously affected by joining in the low rotational speed (630 rpm), having higher strength as compared to higher rotational speed

  19. Low activation R-tokamak with aluminum alloy

    International Nuclear Information System (INIS)

    An aluminum alloy system is considered as an alternative of the first phase design of the R-tokamak. The 1-D calculation showed that the radiation level outside the vacuum vessel could be reduced by a factor of 30 about half a month after a D-T shot, when the aluminum alloy system is adopted instead of a stainless steel system. The aluminum system has weak mechanical strength, is highly conductive, and shows overaging effect at a certain low temperature. Accordingly, it is necessary to overcome these points. The highly conductive aluminum case leads to considerable increase in power consumption. Various problems on the toroidal coils, the vacuum system, and the limiter were studied. The optimization of the device parameters was investigated. (Kato, T.)

  20. Characterization of 2024-T3: An aerospace aluminum alloy

    International Nuclear Information System (INIS)

    The 2024-T3 aerospace aluminum alloy, reported in this investigation, was acquired from a local aerospace industry: Royal Malaysian Air Force (RMAF). The heat treatable 2024-T3 aluminum alloy has been characterized by use of modern metallographic and material characterization techniques (e.g. EPMA, SEM). The microstructural characterization of the metallographic specimen involved use of an optical microscope linked with a computerized imaging system using MSQ software. The use of EPMA and electron microprobe elemental maps enabled us to detect three types of inclusions: Al-Cu, Al-Cu-Fe-Mn, and Al-Cu-Fe-Si-Mn enriched regions. In particular, the presence of Al2CuMg (S-phase) and the CuAl2 (θ') phases indicated precipitation strengthening in the aluminum alloy

  1. Experimental study on activating welding for aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    Huang Yong; Fan Ding

    2005-01-01

    TIG welding and EB welding for aluminum alloy 3003 were carried out to study the effects of activating flux on weld penetration of activating welding for aluminum alloys. SiO2 was used as the activating flux. It is found that, SiO2 can increase the weld penetration and decrease the weld width of FBTIG when the flux gap is small. For A-TIG welding and EB welding with focused mode, the weld penetrations and the weld widths increase simultaneously. SiO2 has little effect on the weld penetration and weld width of EB welding with defocused mode. It is believed that, change of surface tension temperature gradient is not the main mechanism of SiO2 improving weld penetration of activating welding for aluminum alloys.

  2. Comments on process of duplex coatings on aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    Samir H.A.; QIAN Han-cheng(钱翰城); XIA Bo-cai(夏伯才); WU Shi-ming(吴仕明)

    2004-01-01

    Despite the great achievements made in improvement of wear resistance properties of aluminum alloys,their applications in heavy surface load-bearing are limited. Single coating is insufficient to produce the desired combination of surface properties. These problems can be solved through the duplex coatings. The aim of the present study is to overview the research advances on processes of duplex coatings on aluminum alloys combined with micro plasma oxidation process and with other modern processes such as physical vapour deposition and plasma assisted chemical vapour deposition and also to evaluate the performance of micro plasma oxidation coatings in improving the load-bearing, friction and wear resistance properties of aluminum alloys in comparison with other coatings. Wherein, a more detailed presentation of the processes and their performances and disadvantages are given as well.

  3. Pre-review study of the aluminum/alumina master alloy made through pressure infiltration

    International Nuclear Information System (INIS)

    Highlights: • Wetting of the Al2O3 with melt was studied with respect on Al2O3 treatment condition. • Master-alloy with high amount of Al2O3 for subsequent MMC preparation was prepared. • Correlation between parameters of GPI and structure of master-alloy was revealed. • Quality of the interface between aluminum and alumina is tight and consistent. • Particle dissolution within melt was sufficient only after mechanical stirring. - Abstract: The work is focused to prepare Al based master-alloy pellet with 50 vol.% of Al2O3 for subsequent manufacturing of aluminum matrix composites with desired amount of reinforcement (5–20%). Since master-alloy is manufactured via pressure infiltration and proper interface between particles and melt is required for uniform particle distribution within the melt, fundamental correlation between parameters of pressure infiltration and quality of the Al/Al2O3 interface is revealed in this study. Standard observation techniques as 3-D computed tomography (CT), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD) are used for structural characterization. Drop test was used to estimate effect of time, temperature, annealing of Al2O3 and its type on the wettability of Al2O3 with Al. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were used to study changes within the Al2O3 prior infiltration. Stir casting was used to prepare the final composite and dynamical mechanical analysis (DMA) was used to estimate the Young’s modulus of as-cast composite. The proper infiltration parameters was defined in this work and it were shown that the infiltration temperature and pressure have direct correlation on the interface between particle and aluminum

  4. Effect of Holding Time Before Solidification on Double-Oxide Film Defects and Mechanical Properties of Aluminum Alloys

    Science.gov (United States)

    El-Sayed, Mahmoud Ahmed; Salem, Hanadi A. G.; Kandeil, Abdelrazek Youssef; Griffiths, W. D.

    2011-12-01

    Double-oxide films (bifilms) have been held responsible for the variability in mechanical properties of aluminum castings. It has been suggested that the air entrapped inside a bifilm can react with the surrounding melt, leading to its consumption, which might improve the mechanical properties of the castings. In this work the effect of holding the melt before solidification on the distribution of mechanical properties, and by implication on entrained double oxide films, was investigated for several different aluminum alloys. The Weibull moduli of plate castings were determined under tensile conditions, and their fracture surfaces were examined for evidence of oxide films. The results suggested the occurrence of two competing mechanisms during the holding treatment: (1) the consumption of air inside the bifilms by reaction with the surrounding molten metal that may lead to improvements in mechanical properties and (2) the accompanying diffusion of hydrogen into the bifilms, which would be expected to have a deleterious effect on properties.

  5. Effect of pre-treatment on recrystallization and recrystallization textures of cold rolled CC AA 5182 aluminum alloy

    International Nuclear Information System (INIS)

    The effect of pre-treatment on recrystallization and recrystallization textures of cold rolled continuous cast (CC) AA 5182 aluminum alloy as well as on the earing behavior was investigated. The progress of recrystallization was tracked by means of measurements of tensile properties. The texture of cold rolled and annealed samples was determined by X-ray diffraction. The results show that the recrystallization temperature of cold rolled CC AA 5182 aluminum alloy without pre-treatment is about 24 deg. C higher than that of the alloy with pre-treatment. The recrystallization textures of cold rolled CC AA 5182 aluminum alloy are characterized by the R, cube and Goss orientations. The recrystallization textures of cold rolled CC AA 5182 aluminum alloy without pre-treatment exhibit stronger cube and Goss components and a weaker R component than those of the alloy with pre-treatment. The deformed and recovered samples without pre-treatment possess a significantly higher 45 deg. earing than the samples with pre-treatment, while the recrystallized samples without pre-treatment possess a slightly lower 45 deg. earing than the samples with pre-treatment

  6. Superplasticity in powder metallurgy aluminum alloys and composites

    International Nuclear Information System (INIS)

    Superplasticity in powder metallurgy Al alloys and composites has been reviewed through a detailed analysis. The stress-strain curves can be put into 4 categories: classical well-behaved type, continuous strain hardening type, continuous strain softening type and complex type. The origin of these different types of is discussed. The microstructural features of the processed material and the role of strain have been reviewed. The role of increasing misorientation of low angle boundaries to high angle boundaries by lattice dislocation absorption is examined. Threshold stresses have been determined and analyzed. The parametric dependencies for superplastic flow in modified conventional aluminum alloys, mechanically alloyed alloys and Al alloy matrix composites is determined to elucidate the superplastic mechanism at high strain rates. The role of incipient melting has been analyzed. A stress exponent of 2, an activation energy equal to that for grain boundary diffusion and a grain size dependence of 2 generally describes superplastic flow in modified conventional Al alloys and mechanically alloyed alloys. The present results agree well with the predictions of grain boundary sliding models. This suggests that the mechanism of high strain rate superplasticity in the above-mentioned alloys is similar to conventional superplasticity. The shift of optimum superplastic strain rates to higher values is a consequence of microstructural refinement. The parametric dependencies for superplasticity in aluminum alloy matrix composites, however, is different. A true activation energy of superplasticity in aluminum alloy matrix composites, however, is different. A true activation energy of 313 kJ/mol best describes the composites having SiC reinforcements. The role of shape of the reinforcement (particle or whisker) and processing history is addressed. The analysis suggests that the mechanism for superplasticity in composites is interface diffusion controlled grain boundary sliding

  7. Electrorefining of aluminum alloy in ionic liquids at low temperatures

    OpenAIRE

    Kamavaram V.; Mantha D.; Reddy R.G.

    2003-01-01

    The electrorefining of aluminum alloy (A360) in ionic liquids at low temperatures has been investigated. The ionic liquid electrolyte was prepared by mixing anhydrous AlCl3 and 1-Butyl-3- methylimidazolium chloride (BMIC) in appropriate proportions. The effect of the cell voltage temperature, and the composition of the electrolyte on the electrorefining process has been studied. The characterization of the deposited aluminum was performed using scanning electron microscopy (SEM) and X-ray dif...

  8. Improved thermal treatment of aluminum alloy 7075

    Science.gov (United States)

    Cocks, F. H.

    1968-01-01

    Newly developed tempering treatment considerably increases the corrosion resistance of 7075-T6 alloy and concomitantly preserves its yield strength. The results of tests on samples of the alloy subjected to the above treatments show that when the overaging period is 12 hours /at 325 degrees F/, the alloy exhibits a yield strength of 73,000 psi.

  9. Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

    Energy Technology Data Exchange (ETDEWEB)

    Lombardi, A., E-mail: a2lombar@ryerson.ca [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); D' Elia, F.; Ravindran, C. [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); MacKay, R. [Nemak of Canada Corporation, 4600 G.N. Booth Drive, Windsor, Ontario N9C4G8 (Canada)

    2014-01-15

    In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions.

  10. Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

    International Nuclear Information System (INIS)

    In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions

  11. Producing Foils From Direct Cast Titanium Alloy Strip

    Science.gov (United States)

    Stuart, T. A.; Gaspar, T. A.; Sukonnik, I. M.; Semiatan, S. L.; Batawi, E.; Peters, J. A.; Fraser, H. L.

    1996-01-01

    This research was undertaken to demonstrate the feasibility of producing high-quality, thin-gage, titanium foil from direct cast titanium strip. Melt Overflow Rapid Solidification Technology (MORST) was used to cast several different titanium alloys into 500 microns thick strip, 10 cm wide and up to 3 m long. The strip was then either ground, hot pack rolled or cold rolled, as appropriate, into foil. Gamma titanium aluminide (TiAl) was cast and ground to approximately 100 microns thick foil and alpha-2 titanium aluminide (Ti3AI) was cast and hot pack rolled to approximately 70 microns thick foil. CP Ti, Ti6Al2Sn4Zr2Mo, and Ti22AI23Nb (Orthorhombic), were successfully cast and cold-rolled into good quality foil (less than 125 microns thick). The foils were generally fully dense with smooth surfaces, had fine, uniform microstructures, and demonstrated mechanical properties equivalent to conventionally produced titanium. By eliminating many manufacturing steps, this technology has the potential to produce thin gage, titanium foil with good engineering properties at significantly reduced cost relative to conventional ingot metallurgy processing.

  12. Pitting behavior of 2024 aluminum alloy in nitrate solutions

    International Nuclear Information System (INIS)

    Pitting of 2024 aluminum alloy was investigated in chloride-containing nitrate solutions. Potentiostatic and potentiokinetic experiments followed by examination of the sample surface were performed in order to relate the pitting behavior of the alloy to its microstructure. The SEM examination showed that copper-rich particles were preferential sites for pitting. These particles started dissolving during the polarization in nitrate solutions due to the agressivity of nitrate ions toward copper. In the presence of chloride ions, these particles were completely dissolved. Nitrate ions on the other hand appeared to have a very strong inhibitory effect toward pitting in the aluminum matrix. (author)

  13. Forming analysis and application for aluminum-alloy material

    Institute of Scientific and Technical Information of China (English)

    Wei Yuansheng

    2012-01-01

    The increase in car ownership brought about by energy shortages, and environmental crises became more acute. The most effective way to achieve energy saving and emission reduction of car is to improve engine efficiency. In addition to that, lightweight body is the key. Aluminum, magnesium alloy as significant materials of lightweight, and the application amount in the car body is a significant upward trend. However, there is high cost of material, with im- mature applied technology and a series of bottleneck problems. All of them affect general application of lightweight mate- rials. This paper focuses on forming process issues for aluminum, magnesium alloy and the solutions to achieve.

  14. Characterization of Ni–Cr alloys using different casting techniques and molds

    International Nuclear Information System (INIS)

    This study differentiated the mechanical properties of nickel–chromium (Ni–Cr) alloys under various casting techniques (different casting molds and casting atmospheres). These techniques were sampled by a sand mold using a centrifugal machine in ambient air (group I) and electromagnetic induction in an automatic argon castimatic casting machine (group II). The specimen casting used a graphite mold by a castimatic casting machine (group III). The characteristics of the Ni–Cr alloys, yield and ultimate tensile strength, bending modulus, microhardness, diffraction phase, grindability, ability to spring back, as well as ground microstructure and pattern under different casting conditions were evaluated. The group III specimens exhibited the highest values in terms of strength, modulus, hardness, and grindability at a grind rate of 500 rpm. Moreover, group III alloys exhibited smaller grain sizes, higher ability to spring back, and greater ductility than those casted by sand investment (groups I and II). The main factor, “casting mold,” significantly influenced all mechanical properties. The graphite mold casting of the Ni–Cr dental alloys in a controlled atmosphere argon casting system provided an excellent combination of high mechanical properties and good ability to spring back, and preserved the ductile properties for application in Ni–Cr porcelain-fused system. The results can offer recommendations to assist a prosthetic technician in selecting the appropriate casting techniques to obtain the desired alloy properties. - Highlights: • Properties of Ni–Cr alloys using various casting techniques are characterized. • Alloys cast by graphite mold exhibited higher recovery angle and more ductility. • Alloys cast by graphite mold exhibited higher strength and grinding rate. • Alloys in this study increase operative room to adjust the precision for prosthesis

  15. Characterization of Ni–Cr alloys using different casting techniques and molds

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wen-Cheng, E-mail: wencchen@fcu.edu.tw [Advanced Medical Devices and Composites Laboratory, Department of Fiber and Composite Materials, College of Engineering, Feng Chia University, Taichung 40724, Taiwan (China); Teng, Fu-Yuan [Department of Dentistry, Kaohsiung Armed Forces General Hospital, Kaohsiung 802, Taiwan (China); School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Hung, Chun-Cheng [School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan (China)

    2014-02-01

    This study differentiated the mechanical properties of nickel–chromium (Ni–Cr) alloys under various casting techniques (different casting molds and casting atmospheres). These techniques were sampled by a sand mold using a centrifugal machine in ambient air (group I) and electromagnetic induction in an automatic argon castimatic casting machine (group II). The specimen casting used a graphite mold by a castimatic casting machine (group III). The characteristics of the Ni–Cr alloys, yield and ultimate tensile strength, bending modulus, microhardness, diffraction phase, grindability, ability to spring back, as well as ground microstructure and pattern under different casting conditions were evaluated. The group III specimens exhibited the highest values in terms of strength, modulus, hardness, and grindability at a grind rate of 500 rpm. Moreover, group III alloys exhibited smaller grain sizes, higher ability to spring back, and greater ductility than those casted by sand investment (groups I and II). The main factor, “casting mold,” significantly influenced all mechanical properties. The graphite mold casting of the Ni–Cr dental alloys in a controlled atmosphere argon casting system provided an excellent combination of high mechanical properties and good ability to spring back, and preserved the ductile properties for application in Ni–Cr porcelain-fused system. The results can offer recommendations to assist a prosthetic technician in selecting the appropriate casting techniques to obtain the desired alloy properties. - Highlights: • Properties of Ni–Cr alloys using various casting techniques are characterized. • Alloys cast by graphite mold exhibited higher recovery angle and more ductility. • Alloys cast by graphite mold exhibited higher strength and grinding rate. • Alloys in this study increase operative room to adjust the precision for prosthesis.

  16. High Pressure Die Casting of Aluminium and Magnesium Alloys : Grain Structure and Segregation Characteristics

    OpenAIRE

    Laukli, Hans Ivar

    2004-01-01

    Cold chamber high pressure die casting, (HPDC), is an important commercial process for the production of complex near net shape aluminium and magnesium alloy castings. The work presented in the thesis was aimed at investigating the microstructure formation in this type of casting. The solidification characteristics related to the process and the alloys control the formation of grains and defects. This again has a significant impact on the mechanical properties of the castings.The investigatio...

  17. Thermodynamics of Titanium-Aluminum-Oxygen Alloys Studied

    Science.gov (United States)

    Copland, Evan H.; Jacobson, Nathan S.

    2001-01-01

    Titanium-aluminum alloys are promising intermediate-temperature alloys for possible compressor applications in gas-turbine engines. These materials are based on the a2-Ti3Al + g-TiAl phases. The major issue with these materials is high oxygen solubility in a2-Ti3Al, and oxidation of unsaturated alloys generally leads to mixed non-protective TiO2+Al2O3 scales. From phase diagram studies, oxygen saturated a2-Ti3Al(O) is in equilibrium with Al2O3; however, oxygen dissolution has a detrimental effect on mechanical properties and cannot be accepted. To better understand the effect of oxygen dissolution, we examined the thermodynamics of titanium-aluminum-oxygen alloys.

  18. Sliding Wear Behavior of Plasma Sprayed Zirconia Coating on Cast Aluminum against Silicon Carbide Ceramic

    Institute of Scientific and Technical Information of China (English)

    Thuong-Hien LE; Young-Hun CHAE; Seock-Sam KIM

    2005-01-01

    The sliding wear behaviors of ZrO2-22 wt pct MgO (MZ) and ZrO2-8 wt pct Y2O3 (YZ) coatings deposited on a cast aluminum alloy with bond layer (NiCrCoAlY) by plasma spray were investigated under dry test conditions at room temperature. Under all load conditions, the wear mechanisms of the MZ and YZ coatings were almost the same.The material transfer and pullout were involved in the wear process of the studied coatings under the test conditions.The wear rate of the MZ coating was less than that of the YZ coating. While increasing the normal load, the wear rates of the MZ and YZ coatings increased. SEM was used to examine the worn surfaces and to elucidate likely wear mechanisms. Energy dispersive X-ray spectroscopy (EDX) analysis of the worn surfaces indicated that material transfer occurred in the direction from the SiC ball to the disk. Fracture toughness had a significant influence on the wear performance of the coatings. It was suggested that the material transfer played an important role in the wear behavior.

  19. RESEARCH OF MECHANICAL PROPERTY GRADIENT DISTRIBUTION OF Al-Cu ALLOY IN CENTRIFUGAL CASTING

    OpenAIRE

    ZHI SUN; YANWEI SUI; AIHUI LIU; BANGSHENG LI; JINGJIE GUO

    2011-01-01

    Al-Cu alloy castings are obtained using centrifugal casting. The regularity of mechanical property gradient distribution of Al-Cu alloy castings with the same centrifugal radius at different positions is investigated. The result shows that the tensile strength, yield strength, elongation and microscope hardness exhibit the following gradient distribution characteristic — high on both sides and low on the center. The trend of mechanical property gradient distribution of Al-Cu alloy increases w...

  20. Phase-oriented surface segregation in an aluminium casting alloy

    International Nuclear Information System (INIS)

    There have been many reports of the surface segregation of minor elements, especially Mg, into surface layers and oxide films on the surface of Al alloys. LM6 casting alloy (Al-12%Si) represents a challenging system to examine such segregation as the alloy features a particularly inhomogeneous phase structure. The very low but mobile Mg content (approximately 0.001 wt.%), and the surface segregation of modifiers such as Na, mean the surface composition responds in a complex manner to thermal treatment conditions. X-ray photoelectron spectroscopy (XPS) has been used to determine the distribution of these elements within the oxide film. Further investigation by dynamic secondary ion mass spectrometry (DSIMS) confirmed a strong alignment of segregated Na and Mg into distinct phases of the structure.

  1. Effect of Silicon on the casting properties of Al-5.0%Cu alloy

    Institute of Scientific and Technical Information of China (English)

    LI Weijing; CUI Shihai; HAN Jianmin; XU Chao

    2006-01-01

    Poor casting properties restrict the application of high strength casting Al-5.0%Cu alloy.The addition of element can improve the casting properties of this alloy.Effect of Si on the casting properties of Al-5.0%Cu alloy was studied.It has been found that the addition of Si can improve the casting properties of Al-5.0%Cu alloy obviously.With the increase of Si content, the hot cracking tendency of the alloy decreases significantly, and the fluidity of the alloy increases firstly and then decreases slowly.When the content of Si element is higher than 2wt.%, the fluidity of the alloy increases greatly with the increasing of Si content.

  2. New Approaches to Aluminum Integral Foam Production with Casting Methods

    OpenAIRE

    Ahmet Güner; Mustafa Merih Arıkan; Mehmet Nebioglu

    2015-01-01

    Integral foam has been used in the production of polymer materials for a long time. Metal integral foam casting systems are obtained by transferring and adapting polymer injection technology. Metal integral foam produced by casting has a solid skin at the surface and a foam core. Producing near-net shape reduces production expenses. Insurance companies nowadays want the automotive industry to use metallic foam parts because of their higher impact energy absorption properties. In this paper, m...

  3. Mechanical Properties of Solid-State Recycled 4xxx Aluminum Alloy Chips

    Science.gov (United States)

    Tokarski, Tomasz

    2016-06-01

    The direct production of aluminum from bauxite ores is known to be a very energetic-intensive operation compared to other metallurgical processes. Due to energy issues and the rapid increase in aluminum demand, new kinds of aluminum production processes are required. Aluminum waste recycling, which has an advantage of lowering the cost of electric power consumption, is considered to be an alternative route for material manufacturing. In this work, the way of reusing aluminum EN-AC 44000 alloy scraps by hot extrusion was presented. Metal chips of different sizes and morphology were cold compacted into billet form and then hot extruded. Mechanical properties investigations combined with microstructure observations were performed. Mechanical anisotropy behavior of material was evaluated on the base of tensile test experiments performed on samples machined at 0°, 45°, and 90°, respectively, to the extrusion direction. It was found that the initial size of the chips has an influence on the mechanical properties of the received profiles. Samples produced from fine chips revealed higher tensile strength in comparison to larger chips, which can be attributed to a refined microstructure containing fine, hard Si particles and Fe-rich intermetallic phases. Finally, it was found that anisotropic behavior of chip-based profiles is similar to conventionally cast and extruded materials which prove good bonding quality between chips.

  4. Part A - low-aluminum-content iron-aluminum alloys. Part B - commercial-scale melting and processing of FAPY alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Howell, C.R.; Hall, F.; Valykeo, J. [Hoskins Manufacturing Co., Hamburg, MI (United States)

    1996-06-01

    The FAPY is a Fe-16 at. % Al alloy of nominal composition. The aluminum content of the alloy is such that it remains single phase ({alpha}) without the formation of an ordered phase (DO{sub 3}). The alloy has good oxidation resistance at temperatures up to 1000{degrees}C and has shown significantly superior performance as heating elements as compared to the commonly used nickel-based alloy, Nichrome. Although wire for the heating elements has been fabricated from small (15-1b) laboratory heats, for its commercial applications, the wire needs to be producible from large (1200 to 1500-1b) air-melted heats. The purpose of this study was to produce commercial size heats and investigate their mechanical properties and microstructure in the as-cast, hot-worked, and cold-worked conditions. The results of this study are expected to provide: (1) insight into processing steps for large heats into wire under commercial conditions, and (2) the mechanical properties data on commercial size heats in various product forms.

  5. Roles of Alloy Composition and Grain Refinement on Hot Tearing Susceptibility of 7××× Aluminum Alloys

    Science.gov (United States)

    Bai, Q. L.; Li, Y.; Li, H. X.; Du, Q.; Zhang, J. S.; Zhuang, L. Z.

    2016-08-01

    During the production of high-strength 7××× aluminum alloys, hot tearing has set up serious obstacles for attaining a sound billet/slab. In this research, some typical 7××× alloys were studied using constrained rod casting together with the measurement of thermal contraction and load development in the freezing range, aiming at investigating their hot tearing susceptibility. The results showed that the hot tearing susceptibility of an alloy depends not only on the thermal contraction in freezing range, which can decide the accumulated thermal strain during solidification, but also on the amount of nonequilibrium eutectics, which can effectively accommodate the thermally induced deformation. Our investigations reveal that Zn content has very profound effect on hot tearing susceptibility. The Zn/Mg ratio of the alloys also plays a remarkable role though it is not as pronounced as Zn content. The effect of Zn/Mg ratio is mainly associated with the amount of nonequilibrium eutectics. Grain refinement will considerably reduce the hot tearing susceptibility. However, excessive addition of grain refiner may promote hot tearing susceptibility of semi-solid alloy due to deteriorated permeability which is very likely to be caused by the heavy grain refinement and the formation of more intermetallic phases.

  6. Microstructures of ancient and modern cast silver–copper alloys

    Energy Technology Data Exchange (ETDEWEB)

    Northover, S.M., E-mail: s.m.northover@open.ac.uk [Materials Engineering, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Northover, J.P., E-mail: peter.northover@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Rd, Oxford OX1 3PH,UK (United Kingdom)

    2014-04-01

    The microstructures of modern cast Sterling silver and of cast silver objects about 2500 years old have been compared using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), energy dispersive X-ray microanalysis (EDX) and electron backscatter diffraction (EBSD). Microstructures of both ancient and modern alloys were typified by silver-rich dendrites with a few pools of eutectic and occasional cuprite particles with an oxidised rim on the outer surface. EBSD showed the dendrites to have a complex internal structure, often involving extensive twinning. There was copious intragranular precipitation within the dendrites, in the form of very fine copper-rich rods which TEM, X-ray diffraction (XRD), SEM and STEM suggest to be of a metastable face-centred-cubic (FCC) phase with a cube–cube orientation relationship to the silver-rich matrix but a higher silver content than the copper-rich β in the eutectic. Samples from ancient objects displayed a wider range of microstructures including a fine scale interpenetration of the adjoining grains not seen in the modern material. Although this study found no unambiguous evidence that this resulted from microstructural change produced over archaeological time, the copper supersaturation remaining after intragranular precipitation suggests that such changes, previously proposed for wrought and annealed material, may indeed occur in ancient silver castings. - Highlights: • Similar twinned structures and oxidised surfaces seen in ancient and modern cast silver • General precipitation of fine Cu-rich rods apparently formed by discontinuous precipitation is characteristic of as-cast silver. • The fine rods are cube-cube related to the matrix in contrast with the eutectic. • The silver-rich phase remains supersaturated with copper. • Possibly age-related grain boundary features seen in ancient cast silver.

  7. Lead induced intergranular fracture in aluminum alloy AA6262

    NARCIS (Netherlands)

    De Hosson, JTM

    2003-01-01

    The influence of lead on the fracture behavior of aluminum alloy AA6262 is investigated. Under certain conditions, the mode of fracture changes from transgranular microvoid coalescence to an intergranular mechanism. Three different intergranular fracture mechanisms are observed: liquid metal embritt

  8. Fracture behavior of low-density replicated aluminum alloy foams

    NARCIS (Netherlands)

    Amsterdam, E.; Goodall, R.; Mortensen, A.; Onck, P. R.; De Hosson, J. Th. M.

    2008-01-01

    Tensile tests have been performed on replicated aluminum alloy foams of relative density between 4.5% and 8%. During the test the electrical resistance was measured with a four-point set-up and the displacements along the gage section were measured using a digital image correlation (DIC) technique.

  9. Effects of high frequency current in welding aluminum alloy 6061

    Science.gov (United States)

    Fish, R. E.

    1968-01-01

    Uncontrolled high frequency current causes cracking in the heat-affected zone of aluminum alloy 6061 weldments during tungsten inert gas ac welding. Cracking developed when an improperly adjusted superimposed high frequency current was agitating the semimolten metal in the areas of grain boundary.

  10. Study made of ductility limitations of aluminum-silicon alloys

    Science.gov (United States)

    Bailey, W. A.; Frederick, S. F.

    1967-01-01

    Study of the relation between microstructure and mechanical properties of aluminum-silicon alloys determines the cause of the variations in properties resulting from differences in solidification rate. It was found that variations in strength are a consequence of variations in ductility and that ductility is inversely proportional to dendrite cell size.

  11. Testing of 2219-T87 aluminum alloy at 40K

    International Nuclear Information System (INIS)

    The tensile and fracture properties of heavy section (1.5 inches thick) 2219-T87 plate aluminum alloy at 40K were determined. Transverse and longitudinal crack growth parameters were measured. Tensile specimens were taken at L, T, and ST orientations and tensile data is tabulated. K/sub Ic/ tests results and fatigue-crack growth data are summarized

  12. Titanium-zirconium-phosphonate hybrid film on 6061 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    Shuanghong WANG; Lei WANG; Changsheng LIU

    2011-01-01

    Three titanium-zirconium-phosphonate hybrid films were formed on AA6061 aluminum alloy by immersing in fluorotitanic acid and fluorozirconic acid based solution containing different phosphonic acids for protective coatings of aluminium alloy. The corrosion resistance of three hybrid films as the substitute for chromate film were evaluated and compared. The neutral salt spray test was explored,the immersion test was conducted and electrochemical test was also executed. The hybrid films exhibited well-pleasing corrosion resistance and adhesion to epoxy resin paints. It was found out that the hybrid films could efficiently be a substitute for chromate based primer over aluminium alloy.

  13. New all aluminum alloy ultrahigh vacuum system and fittings

    International Nuclear Information System (INIS)

    The Al-ICF ALFLAT FLANGE corresponds to the ordinary stainless steel Conflat flange. The Al-ICF ALFLAT FLANGE is made of special aluminum alloy 2219-T87 by forging. It has the highest strength at elevated high temperature among all aluminum alloys as well as superior weldability and stress corrosion cracking resistivity. CrN or TiC coating on the flange surface by ion plating. The CrN or TiC treatment on the surface gave nearly protection against sticking between the knife edge of the flange and the aluminum gasket and surface scratching. Sealing surface of the knife edge for the Helicoflex is finished to a smooth mirror surface by a diamond tool. (author)

  14. A super-ductile alloy for the die-casting of aluminium automotive body structural components

    OpenAIRE

    Watson, D.; Ji, S; Fan, Z.

    2014-01-01

    Super-ductile die-cast aluminium alloys are critical to future light-weighting of automotive body structures. This paper introduces a die-cast aluminium alloy that can satisfy the requirements of these applications. After a review of currently available alloys, the requirement of a die-cast aluminium alloy for automotive body structural parts is proposed and an Al-Mg-Si system is suggested. The effect of the alloying elements, in the composition, has been investigated on the microstructure an...

  15. The Influence of Casting Conditions on the Microstructure of As-Cast U-10Mo Alloys: Characterization of the Casting Process Baseline

    Energy Technology Data Exchange (ETDEWEB)

    Nyberg, Eric A.; Joshi, Vineet V.; Lavender, Curt A.; Paxton, Dean M.; Burkes, Douglas

    2013-12-13

    Sections of eight plate castings of uranium alloyed with 10 wt% molybdenum (U-10Mo) were sent from Y-12 to the Pacific Northwest National Laboratory (PNNL) for microstructural characterization. This report summarizes the results from this study.

  16. Characterization of room-temperature damping in aluminum-indium alloys

    International Nuclear Information System (INIS)

    Damping of aluminum-indium alloys with up to 16 wt pct indium was studied at fixed frequencies between 0.1 and 5.0 Hz. In the strain amplitude-independent regime, the damping initially decreased with the addition of indium and reached a minimum at 10 wt pct. The frequency-dependent damping was modeled for these alloys using a diffusion-controlled dislocation relaxation model for the high-temperature background, and an expression for multiphase materials was given. At indium concentrations greater than 10 wt pct, a relaxation peak at 25 C and 1.0 Hz was observed. This peak was associated with the indium inclusions, and an activation energy of 0.6 ± 0.2 eV was experimentally determined. It was suggested that a critical indium inclusions size is necessary before the relaxation peak becomes appreciable and that this damping mechanism is analogous to that observed for graphite in gray cast irons

  17. System for ultra high vacuum made of aluminum alloys

    International Nuclear Information System (INIS)

    We have developed the system for ultra high vacuum made of aluminum alloys for proton and electron synchrotron. This is the first system for ultra high vacuum in which bakable metal seal flange and small diametral bellows of aluminum alloys have been put to practical use. The system consists of the flange protected by a CrN thin film and made of 2219-T87 alloy, the chamber made of 6063-T6 alloy, the aluminum metal gasket of Helico Flex and the bellows made of 5052 alloy. As a result of experiments at the National Laboratory for High Energy Physics (KEK), it had been confirmed that this system shows the special qualities of ultra high vacuum operation, resistance to hard radiation and baking and cooling operations. Up to now, this system has been widely used for the beam lines of the booster synchrotron utilization facility, K1, K2, linac, PI 1 and EP2-B extension of the KEK proton synchrotron. We investigate that this system is applicable to nuclear energy utilization facility and general vacuum apparatus. (author)

  18. Development of environmentally friendly cast alloys. High-zinc Al alloys

    Directory of Open Access Journals (Sweden)

    W.K. Krajewski

    2010-10-01

    Full Text Available Purpose: The main purpose of this paper is presenting the results obtained in years 2007 – 2010 in frame of the project Marie Curie Transfer of Knowledge – CastModel. The project was focused, among others, at elaborating new, environmentally friendly cast alloys based on the Al-Zn system. Particularly, efforts were aimed at improving ductility of the sand cast high-zinc aluminium alloys (HZnAl by using the newly elaborated master alloys, based on the Al-Zn-Ti system.Design/methodology/approach: The presented work is focused on the nucleation of the high-zinc Al-20 wt% Zn (HZnAl AlZn20 alloy, known as the high damping one, aiming at improving plastic properties of the sand castings. The melted alloy was nucleated with AlTi5B1 (TiBAl and AlTi3C0.15 (TiCAl refiners as well as with the newly introduced ZnAl-Ti3 one. During the research the following experimental techniques were used: LM, SEM-EBSD, EDS, TA, DSC, Quantitative Metallography, UTS, Elongation and Attenuation coefficient measurements.Findings: During the performed examinations it was found out that significant increasing of the grain population of the inoculated alloy increases plasticity represented by elongation. The attenuation coefficient of the nucleated alloy, measured using an Olympus Epoch XT device, preserves its high value. The results obtained allow to characterize the examined AlZn20 alloy as promissive, having good strength and damping properties as well as the environmentally friendly alloy because of its comparatively low melting temperatures.Practical implications: The grain-refined high-zinc aluminium alloys can be used as the high damping substitutes of the traditional, more energy consumable Fe-based foundry alloys.Originality/value: The newly elaborated ZnAl-Ti based master alloys show high refining potency and quick dissolution in low melting temperatures of about 500°C, and are the promissive alternatives of the traditional AlTi-based ones.

  19. Cleavage crystallography of liquid metal embrittled aluminum alloys

    Science.gov (United States)

    Reynolds, A. P.; Stoner, G. E.

    1991-01-01

    The crystallography of liquid metal-induced transgranular cleavage in six aluminum alloys having a variety of microstructures has been determined via Laue X-ray back reflection. The cleavage crystallography was independent of alloy microstructure, and the cleavage plane was 100-plane oriented in all cases. It was further determined that the cleavage crystallography was not influenced by alloy texture. Examination of the fracture surface indicated that there was not a unique direction of crack propagation. In addition, the existence of 100-plane cleavage on alloy 2024 fracture surfaces was inferred by comparison of secondary cleavage crack intersection geometry on the 2024 surfaces with the geometry of secondary cleavage crack intersections on the test alloys.

  20. Fabrication of superhydrophobic nanostructured surface on aluminum alloy

    Science.gov (United States)

    Jafari, R.; Farzaneh, M.

    2011-01-01

    A superhydrophobic surface was prepared by consecutive immersion in boiling water and sputtering of polytetrafluoroethylene (PTFE or Teflon®) on the surface of an aluminum alloy substrate. Immersion in boiling water was used to create a micro-nanostructure on the alloy substrate. Then, the rough surface was coated with RF-sputtered Teflon film. The immersion time in boiling water plays an important role in surface morphology and water repellency of the deposited Teflon coating. Scanning electron microscopy images showed a "flower-like" structure in first few minutes of immersion. And as the immersion time lengthened, a "cornflake" structure appeared. FTIR analyses of Teflon-like coating deposited on water treated aluminum alloy surfaces showed fluorinated groups, which effectively reduce surface energy. The Teflon-like coating deposited on a rough surface achieved with five-minute immersion in boiling water provided a high static contact angle (˜164°) and low contact angle hysteresis (˜4°).

  1. Dynamic Crystallization: An Influence on Degree of Prior Deformation and Mechanical Strength of 6063 Aluminum Alloy

    Directory of Open Access Journals (Sweden)

    Gbenebor, O.P

    2012-09-01

    Full Text Available This research is aimed at investigating the influence dynamic solidification of melts on degree of mechanical deformation and mechanical strength of 6063 aluminum alloy. Cylindrical samples of 14mm diameter and 140mm long were die cast following two techniques – vibration and static. Prior deformation via forging was imposed on each solidified sample to achieve 7%, 14%, 21% and 28% thickness reductions respectively for each casting technique. Average deformation load, average hammer velocities and the average energy absorbed were recorded. Tensile properties of each sample were studied via the use of Monsanto tensometer. Mechanical agitation of mould and its content increased the machinability of the alloy even at higer pre deformation. This was justified by the failure of the 28% reduction sample cast on static floor during machining to a tensile piece. The energy absorbed during deformation influences the tensile strength of the material. This increases with increase in percentage deformation except for 28% reduction whose magnitude was lower than that subjected to 21% reduction; vibrated samples possessed superior properties. From results obtained, vibrating a sample and subjecting to 21% pre-deformation possessed the best tensile strength.

  2. Effect of homogenization and alloying elements on hot deformation behaviour of 1XXX series aluminum alloys

    Science.gov (United States)

    Shakiba, Mohammad

    In the present study, the effect of different alloying elements as well as the homogenization treatment on the hot workability and microstructure of dilute Al-Fe-Si alloys was investigated using hot compression tests, optical microscopy, SEM, electron EBSD, TEM, electrical conductivity measurements. The effect of the homogenization treatment on the microstructure and hot workability of two dilute Al-Fe-Si alloys was first investigated. Homogenization promoted the phase transformation from the metastable AlmFe or alpha-AlFeSi phase to the Al3Fe equilibrium phase and induced a significant change in solute levels in the solid solution. Homogenization at 550°C significantly reduced the solid solution levels due to the elimination of the supersaturation originating from the cast ingot and produced the lowest flow stress under all of the deformation conditions studied. The hot deformation behavior of dilute Al-Fe-Si alloys containing different amounts of Fe (0.1 to 0.7 wt%) and Si (0.1 to 0.25 wt%) was studied by uniaxial compression tests conducted at various temperatures (350-550 °C) and strain rates (0.01-10 s-1). The flow stress of the 1xxx alloys increased with increasing Fe and Si content. Increasing the Fe content from 0.1 to 0.7% raised the flow stress by 11-32% in Al-Fe-0.1Si alloys, whereas the flow stress increased 5-14% when the Si content increased from 0.1 to 0.25% in Al-0.1Fe-Si alloys. The experimental stress-strain data were employed to drive constitutive equations correlating flow stress, deformation temperature and strain rate considering the influence of the chemical composition. The microstructural analysis results revealed that dynamic recovery is the sole softening mechanism during hot deformation of dilute Al-Fe-Si alloys. Increasing the Fe and Si content retarded dynamic recovery and resulted in a decrease in the subgrain size and mean misorientation angle of the boundaries. Furthermore, the hot deformation behavior of dilute Al-Fe-Si alloys

  3. Microstructure and Mechanical Properties of Hyper-eutectic Al-Si Alloys Fabricated by Spray Casting

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Microstructure and mechanical properties of hyper-eutectic Al-Si alloy fabricated by spray casting were investigated and then these results were compared with those by squeeze cast. The spray-cast specimen was found to have finer Si particles (~5μm) compared to the squeeze-cast specimen (10-25μm). The tensile strength and elongation of the spray-cast specimen are also higher than those of the squeeze cast one. It was considered that the increased mechanical properties of the spray-cast specimen were mainly due to finer size of the Si particles distributed in Al matrix.

  4. Study on interfacial heat transfer coefficient at metal/die interface during high pressure die casting process of AZ91D alloy

    Directory of Open Access Journals (Sweden)

    GUO Zhi-peng

    2007-02-01

    Full Text Available The high pressure die casting (HPDC process is one of the fastest growing and most efficient methods for the production of complex shape castings of magnesium and aluminum alloys in today’s manufacturing industry.In this study, a high pressure die casting experiment using AZ91D magnesium alloy was conducted, and the temperature profiles inside the die were Measured. By using a computer program based on solving the inverse heat problem, the metal/die interfacial heat transfer coefficient (IHTC was calculated and studied. The results show that the IHTC between the metal and die increases right after the liquid metal is brought into the cavity by the plunger,and decreases as the solidification process of the liquid metal proceeds until the liquid metal is completely solidified,when the IHTC tends to be stable. The interfacial heat transfer coefficient shows different characteristics under different casting wall thicknesses and varies with the change of solidification behavior.

  5. Microstructural characterization of as-cast Co-B alloys

    International Nuclear Information System (INIS)

    This work presents results of microstructural characterization of as-cast Co-B alloys. Samples of different compositions were prepared by arc melting Co (min. 99.97%) and B (min. 99.5%) under argon atmosphere in a water-cooled copper crucible with non-consumable tungsten electrode and titanium getter. All samples were characterized by scanning electron microscopy (SEM) in back-scattered electron (BSE) mode, X-ray diffraction (XRD) and wavelength dispersive spectrometry (WDS). A good agreement is observed between the obtained microstructures and those expected by the currently accepted Co-B phase diagram

  6. The microstructure and precipitation kinetics of a cast aluminium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Ovono, D. Ovono [Laboratoire Roberval, University of Technology of Compiegne, 60205 Compiegne (France)]. E-mail: delavand.ovono-ovono@utc.fr; Guillot, I. [Centre d' Etudes de Chimie Metallurgie, UPR2801 CNRS, 94407 Vitry-sur-Seine (France); Massinon, D. [Fonderie Montupet, 60181 Nogent-sur-Oise (France)

    2006-08-15

    The microstructure of a cast Al-Si-Cu alloy was studied quantitatively in detail by a combination of differential scanning calorimetry, scanning electron microscopy, scanning tunnelling microscopy and transmission electron microscopy. The kinetics of coarsening can be described by the classical ripening theory. The plot of the rate constant of coarsening and the temperature follows an Arrhenius behaviour with an activation energy of about 140.4 kJ/mol{sup -1}, which is approximately the activation energy for diffusion of Cu and/or Si in Al, indicating diffusion-controlled precipitate growth.

  7. Fatigue Characteristics and Quality Index of A357 Type Semi-Solid Aluminum Castings Used for Automotive Application

    Science.gov (United States)

    Bouazara, M.; Bouaicha, A.; Ragab, Kh. A.

    2015-08-01

    The present work aims to investigate the fatigue characteristics of automotive lower suspension arm made of semi-solid A357 aluminum castings using metallurgical and analytical approaches. The fatigue life calculations of analytical model are used to identify and introduce the model parameters based on the suspension arm material followed by analyzing the load-number of cycles fatigue curve. The critical stress areas capable of initiating cracks during fatigue tests are detected using ABAQUS software followed by the installation of strain gages on the suspension arm to calculate maximum stress. The fatigue experiments are carried out to compare the results of the analytical method with the experimental endurance curves traced by lower suspension arm samples. Microstructure characteristics of the semi-solid A357 under T6 heat treatment conditions are examined using scanning electron microscope. The results show that the fatigue life and the quality index of alloys investigated are affected by casting technique, castings design, microstructural characterization, and heat treatment condition.

  8. Reduction of Oxidative Melt Loss of Aluminum and Its Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Subodh K. Das; Shridas Ningileri

    2006-03-17

    This project led to an improved understanding of the mechanisms of dross formation. The microstructural evolution in industrial dross samples was determined. Results suggested that dross that forms in layers with structure and composition determined by the local magnesium concentration alone. This finding is supported by fundamental studies of molten metal surfaces. X-ray photoelectron spectroscopy data revealed that only magnesium segregates to the molten aluminum alloy surface and reacts to form a growing oxide layer. X-ray diffraction techniques that were using to investigate an oxidizing molten aluminum alloy surface confirmed for the first time that magnesium oxide is the initial crystalline phase that forms during metal oxidation. The analytical techniques developed in this project are now available to investigate other molten metal surfaces. Based on the improved understanding of dross initiation, formation and growth, technology was developed to minimize melt loss. The concept is based on covering the molten metal surface with a reusable physical barrier. Tests in a laboratory-scale reverberatory furnace confirmed the results of bench-scale tests. The main highlights of the work done include: A clear understanding of the kinetics of dross formation and the effect of different alloying elements on dross formation was obtained. It was determined that the dross evolves in similar ways regardless of the aluminum alloy being melted and the results showed that amorphous aluminum nitride forms first, followed by amorphous magnesium oxide and crystalline magnesium oxide in all alloys that contain magnesium. Evaluation of the molten aluminum alloy surface during melting and holding indicated that magnesium oxide is the first crystalline phase to form during oxidation of a clean aluminum alloy surface. Based on dross evaluation and melt tests it became clear that the major contributing factor to aluminum alloy dross was in the alloys with Mg content. Mg was

  9. Ceramic filters for bulk inoculation of nickel alloy castings

    Directory of Open Access Journals (Sweden)

    F. Binczyk

    2011-07-01

    Full Text Available The work includes the results of research on production technology of ceramic filters which, besides the traditional filtering function, playalso the role of an inoculant modifying the macrostructure of cast nickel alloys. To play this additional role, filters should demonstratesufficient compression strength and ensure proper flow rate of liquid alloy. The role of an inoculant is played by cobalt aluminateintroduced to the composition of external coating in an amount from 5 to 10 wt.% . The required compression strength (over 1MPa isprovided by the supporting layers, deposited on the preform, which is a polyurethane foam. Based on a two-level fractional experiment24-1, the significance of an impact of various technological parameters (independent variables on selected functional parameters of theready filters was determined. Important effect of the number of the supporting layers and sintering temperature of filters after evaporationof polyurethane foam was stated.

  10. Microstructural characterization of as-cast Cr-B alloys

    International Nuclear Information System (INIS)

    Accurate knowledge of several Me-B (Me - Metal) phase diagrams are important to evaluate higher order systems such as Me-Si-B ternaries. This work presents results of microstructural characterization of as-cast Cr-B alloys which are significant to assess the liquid compositions associated to most of the invariant reactions of this system. Alloys of different compositions were prepared by arc melting pure Cr and B pressed powder mixtures under argon atmosphere in a water-cooled copper crucible with non-consumable tungsten electrode and titanium getter. The phases were identified by scanning electron microscopy (SEM), using back-scattered electron (BSE) image mode and X-ray diffraction (XRD). In general, a good agreement was found between our data and those from the currently accepted Cr-B phase diagram

  11. Fatigue of an Al-Si gravity die casting alloy

    Energy Technology Data Exchange (ETDEWEB)

    Styles, C.M. [Defence Evaluation and Res. Agency, Farnborough (United Kingdom). MSS; Reed, P.A.S.

    2000-07-01

    Fatigue crack initiation, short crack and long crack growth studies were performed on a high performance cast piston type alloy (Al-Si-Cu-Ni-Mg). Crack initiation was mainly associated with large blocky Si particles although a few cracks were initiated at clusters of FeNiAl{sub 9} intermetallics. Classical short crack growth was shown with crack arrest for up to 15000 fatigue cycles at second phase particles. Long crack growth showed no evidence of stage I like facets near threshold or ductile striations in the mid {delta}K region. A large number of fractured Si particles were, however, observed on the fracture surfaces and crack profiles the incidence of which increased with {delta}K. The findings of this study suggest this alloy is brittle in nature with the Si particle content generally controlling fatigue crack initiation and growth. (orig.)

  12. Intermetallic phase particles in cast AlSi5Cu1Mg and AlCu4Ni2Mg2 aluminium alloys

    Directory of Open Access Journals (Sweden)

    G. Mrówka-Nowotnik

    2009-08-01

    Full Text Available Purpose: In the technical Al alloys even small quantity of impurities - Fe and Mn - causes the formation of new phase components. Intermetallic particles form either on solidification or whilst the alloy is at a relatively high temperature in the solid state, e.g. during homogenization, solution treatment or recrystallization. The exact composition of the alloy and casting condition will directly influence the selection and volume fraction of intermetallic phases. The main objective of this study was to analyze the morphology and composition of complex microstructure of intermetallic phases in cast AlSi5Cu1Mg and AlCu4Ni2Mg2 aluminium alloys.Design/methodology/approach: In this study, several methods were used such as: optical light microscopy (LM, scanning (SEM electron microscopy in combination with X-ray analysis (EDS using polished sample, and X-ray diffraction (XRD to identify intermetallics in cast AlSi5Cu1Mg and AlCu4Ni2Mg2 aluminum alloys.Findings: The results show that the microstructure of cast AlSi5Cu1Mg and AlCu4Ni2Mg2 aluminum alloys in T6 condition consisted a wide range of intermetallic phases. By using various instruments (LM, SEM, XRD and techniques (imagine, EDS following intermetallic phases were identified: β-Al5FeSi, α-Al15(FeMn3Si - in AlSi5Cu1Mg alloy and Al7Cu4Ni, Al12Cu23Ni, Al2CuMg, AlCuFeNi - in AlCu4Ni2Mg2 alloy.Research limitations/implications: In order to complete and confirm obtained results it is recommended to perform further analysis of the investigated aluminium alloys. Therefore it is planned to include in a next studies, microstructure analysis of the alloys by using transmission electron microscopy technique (TEM.Practical implications: Since the morphology, crystallography and chemical composition affect the intermetallic properties, what involves changes of alloy properties, from a practical point of view it is important to understand their formation conditions in order to control final constituents of

  13. Investigations of microstructure and dislocations of cast magnesium alloys

    Directory of Open Access Journals (Sweden)

    T. Tański

    2010-09-01

    Full Text Available Purpose: The microstructures and the dislocation arrangements in the cast magnesium alloy have been investigated using transmission electron microscopy and high-resolution transmission electron microscopy. In this paper are presented also the results of phase morphology investigation of an new developed Mg alloy. Such studies are of great interest for the metal industry, mainly the automobile industry, were the improvement of cast elements quality is crucial for economic and quality reason and depends mainly on properly performed controlling process of the production parameters. There are presented especially the effect of heat treatment on the size and distribution of the precipitation occurred in the matrix.Design/methodology/approach: The basic assumptions of this work are realised an Universal Metallurgical Simulator and Analyzer. The solidification process itself is analysed using the UMSA device by appliance of the Derivative Thermo Analysis. The thermal analysis was performed at a low but regulated cooling rate in a range of 0.2 ºC to ca. 3 ºC. Cooling curve for the thermal analysis was performed using a high sensitivity thermocouples of the K type, covered with a stainless steel sheath. The data were acquired by a high speed data acquisition system linked to a PC computer. Two different types of samples were used, bulk-cylindrical, and thin-walled cylindrical. Metallographic investigation were made on cross section samples of a engine bloc. Non-equilibrium heating and cooling process conditions were applied to achieve changes in shape and distribution of the phases such as Al2Cu and Si.Findings: During the investigation Dislocation networks are found to increase with deformation in all cases. The dislocation networks have been found in the g- Mg17Al12 phase as well as in the matrix in the investigation magnesium alloys. The crystallographic orientation relationship are: (1 01 α-Mg ║ (10 Mg17Al12 and [11 0] α-Mg ║ [111] Mg17Al12

  14. Cavitation erosion mechanism of titanium alloy radiation rods in aluminum melt.

    Science.gov (United States)

    Dong, Fang; Li, Xiaoqian; Zhang, Lihua; Ma, Liyong; Li, Ruiqing

    2016-07-01

    Ultrasound radiation rods play a key role in introducing ultrasonic to the grain refinement of large-size cast aluminum ingots (with diameter over 800mm), but the severe cavitation corrosion of radiation rods limit the wide application of ultrasonic in the metallurgy field. In this paper, the cavitation erosion of Ti alloy radiation rod (TARR) in the semi-continuous direct-chill casting of 7050 Al alloy was investigated using a 20kHz ultrasonic vibrator. The macro/micro characterization of Ti alloy was performed using an optical digital microscopy and a scanning electron microscopy, respectively. The results indicated that the cavitation erosion and the chemical reaction play different roles throughout different corrosion periods. Meanwhile, the relationship between mass-loss and time during cavitation erosion was measured and analyzed. According to the rate of mass-loss to time, the whole cavitation erosion process was divided into four individual periods and the mechanism in each period was studied accordingly. PMID:26964935

  15. Precision casting of Ti-15V-3Cr-3Al-3Sn alloy setting

    OpenAIRE

    Nan Hai; Liu Changkui; Huang Dong

    2008-01-01

    In this research, Ti-15V-3Cr-3Al-3Sn alloy ingots were prepared using ceramic mold and centrifugal casting. The Ti-15V-3Cr-3Al-3Sn setting casting, for aeronautic engine, with 1.5 mm in thickness was manufactured. The alloy melting process, precision casting process, and problems in casting application were discussed. Effects of Hot Isostatic Pressing and heat treatment on the mechanical properties and microstructure of the Ti-15V-3Cr-3Al-3Sn alloy were studied.

  16. Precision casting of Ti-15V-3Cr-3Al-3Sn alloy setting

    Directory of Open Access Journals (Sweden)

    Nan Hai

    2008-02-01

    Full Text Available In this research, Ti-15V-3Cr-3Al-3Sn alloy ingots were prepared using ceramic mold and centrifugal casting. The Ti-15V-3Cr-3Al-3Sn setting casting, for aeronautic engine, with 1.5 mm in thickness was manufactured. The alloy melting process, precision casting process, and problems in casting application were discussed. Effects of Hot Isostatic Pressing and heat treatment on the mechanical properties and microstructure of the Ti-15V-3Cr-3Al-3Sn alloy were studied.

  17. Hydrogen interactions in aluminum-lithium alloys

    Science.gov (United States)

    Smith, S. W.; Scully, J. R.

    1991-01-01

    A program is described which seeks to develop an understanding of the effects of dissolved and trapped hydrogen on the mechanical properties of selected Al-Li-Cu-X alloys. A proposal is made to distinguish hydrogen (H2) induced EAC from aqueous dissolution controlled EAC, to correlate H2 induced EAC with mobile and trapped concentrations, and to identify significant trap sites and hydride phases (if any) through use of model alloys and phases. A literature review shows three experimental factors which have impeded progress in the area of H2 EAC for this class of alloys. These are as listed: (1) inter-subgranular fracture in Al-Li alloys when tested in the S-T orientation in air or vacuum make it difficult to readily detect H2 induced fracture based on straight forward changes in fractography; (2) the inherently low H2 diffusivity and solubility in Al alloys is further compounded by a native oxide which acts as a H2 permeation barrier; and (3) H2 effects are masked by dissolution assisted processes when mechanical testing is performed in aqueous solutions.

  18. Microstructure and Thermomechanical Properties of Magnesium Alloys Castings

    Directory of Open Access Journals (Sweden)

    P. Lichý

    2012-04-01

    Full Text Available Magnesium alloys thanks to their high specific strength have an extensive potential of the use in a number of industrial applications. The most important of them is the automobile industry in particular. Here it is possible to use this group of materials for great numbers of parts from elements in the car interior (steering wheels, seats, etc., through exterior parts (wheels particularly of sporting models, up to driving (engine blocks and gearbox mechanisms themselves. But the use of these alloys in the engine structure has its limitations as these parts are highly thermally stressed. But the commonly used magnesium alloys show rather fast decrease of strength properties with growing temperature of stressing them. This work is aimed at studying this properties both of alloys commonly used (of the Mg-Al-Zn, Mn type, and of that ones used in industrial manufacture in a limited extent (Mg-Al-Sr. These thermomechanical properties are further on complemented with the microstructure analysis with the aim of checking the metallurgical interventions (an effect of inoculation. From the studied materials the test castings were made from which the test bars for the tensile test were subsequently prepared. This test took place within the temperature range of 20°C – 300°C. Achieved results are summarized in the concluding part of the contribution.

  19. The technology of precision casting of titanium alloys by centrifugal process

    Directory of Open Access Journals (Sweden)

    A. Karwiński

    2011-07-01

    Full Text Available The article describes the development of a procedure for the preparation of foundry ceramic moulds and making first test castings. The presented studies included:development of technological parameters of the ceramic mould preparation process using water-based zirconium binders and zirconia ceramic materials, where moulds are next used for the centrifugal casting of titanium alloys melted in vacuum furnaces, designing of pouring process using simulation software, making test castings,testing and control of the casting properties. The technological process described in this paper enables making castings in titanium alloys weighing up to about 500 g and used in the majority of technical applications.

  20. Influence of hydrogen content on the behavior of grain refinement in hypereutectic aluminum-silicon alloy

    Institute of Scientific and Technical Information of China (English)

    Lina Hu; Xiufang Bian; Youfeng Duan

    2004-01-01

    Dissolved hydrogen is harmful to mechanical properties of refined hypereutectic aluminum-silicon alloys. In the present work, by using a stepped-form mold and the hydrogen-detecting instrument HYSCAN Ⅱ, the relationship between the initial hydrogen content in the melt and the refinement effect on the casting of hypereutectic aluminum-silicon alloy was investigated. The experimental results show that the cooling rate, the hydrogen content and the grain refinement effect are three interactive factors. When the hydrogen content is above 0.20 mL/100 g and the cooling rate is lower than that in 50 mm-thick step, hydrogen dissolved in the alloy melt influences the grain refinement effect. With increasing the cooling rate, the critical hydrogen content increases too. It is expected that much hydrogen in the melt make the net interfacial energy larger than or equal to zero, resulting in the shielding of the particles AlP during solidification and that the critical gas content is closely related to the critical radius of embryo bubbles.

  1. Effects of minor scandium on as-cast microstructure, mechanical properties and casting fluidity of ZA84 magnesium alloy

    International Nuclear Information System (INIS)

    The effects of minor Sc on the as-cast microstructure, mechanical properties and casting fluidity of the ZA84 magnesium alloy were investigated. The results indicate that the Mg32(Al,Zn)49 phase in the ZA84 alloy is refined with the addition of 0.12-0.35 wt.% Sc, and the formation of the Mg32(Al,Zn)49 phase is suppressed. An increase in Sc amount from 0.12 wt.% to 0.35 wt.% causes the morphology of the Mg32(Al,Zn)49 phase to gradually change from coarse continuous and/or quasi-continuous net to relatively fine quasi-continuous and/or disconnected shapes. In addition, it is shown that the tensile and creep properties of the ZA84 alloy are improved, but the casting fluidity of the alloy is decreased with the addition of 0.12-0.35 wt.% Sc.

  2. MICROSTRUCTURE AND PROPERTIES OF ZL201 ALLOY OBTAINED BY NEAR-LIQUIDUS ELECTROMAGNETIC CASTING

    Institute of Scientific and Technical Information of China (English)

    P. Wang; L.F. Sh; G.M. Lu; J.Z. Cui

    2005-01-01

    The microstructures of ZL201 alloy slurry prepared by near-liquidus electromagnetic casting(NLEMC), electromagnetic casting(EMC), and near-liquidus casting(NLC) were investigated by means of electron microscopy and image analysis. Mechanical properties of as-cast alloys were determined. The results show that the NLEMC induces a fine, uniform, and equiaxed grain structure with a mean equal-area-circle grain diameter of 32.8μm. The as-cast alloy has a hardness of HV122.8 and a tensile strength of 368MPa. Both of them are better than those of the alloys prepared by EMC and by NLC. The mechanism of grain refinement in the NLEMC alloy slurry was discussed.

  3. Hot corrosion resistance of nickel-chromium-aluminum alloys

    Science.gov (United States)

    Santoro, G. J.; Barret, C. A.

    1977-01-01

    The hot corrosion resistance of nickel-chromium-aluminum alloys was examined by cyclically oxidizing sodium sulfate-coated specimens in still air at 900, 1000, and 1100 C. The compositions tested were within the ternary region: Ni, Ni-50 at.% Cr, and Ni-50 at.% Al. At each temperature the corrosion data were statistically fitted to a third order regression equation as a function of chromium and aluminum contents. From these equations corrosion isopleths were prepared. Compositional regions with the best hot corrosion resistance were identified.

  4. In situ purification, alloying and casting methodology for metallic plutonium

    Science.gov (United States)

    Lashley, Jason C.; Blau, Michael S.; Staudhammer, Karl P.; Pereyra, Ramiro A.

    Plutonium metal that has been double ER (electrorefined/electrorefining) was further purified via zone refining, using a floating molten zone to minimize the introduction of impurities. The temperature of the molten zone was 750°C, and the atmosphere was 10 -5 Pa. A total of ten zone refining passes were made at a travel rate of 1.5 cm/h. There were 19 elements reduced to quantities below the minimum detectable limits (MDL) by zone refining, while P, K, and W were significantly reduced. The zone-refined metal was then used in an in situ distillation, alloying, and casting step to prepare tapered specimens for single-crystal growth experiments. Specifically, 241Am was distilled from Pu metal by levitating Pu metal with 1 wt% Ga in the melt in a Crystallox vertical electromagnetic levitation crucible at 10 -5 Pa. The Pu is alloyed with Ga to stabilize the δ phase (fcc symmetry) upon solidification. The Pu was chill-cast directly from the electromagnetic levitation field into 1- cm tapered specimens. A water-cooled ceramic mold was used, and the Pu metal was cooled at a rate of 100°C/min. A microstructure examination of the specimen showed 10 × 25 μm acicular grains with a density of 15.938 g/cm 3 (±0.002 g/cm 3).

  5. Microstructure and mechanical properties of a new type of austempered boron alloyed high silicon cast steel

    OpenAIRE

    Chen Xiang; Li Yanxiang

    2013-01-01

    In the present paper, a new type of austempered boron alloyed high silicon cast steel has been developed, and its microstructures and mechanical properties at different temperatures were investigated. The experimental results indicate that the boron alloyed high silicon cast steel comprises a dendritic matrix and interdendritic eutectic borides in as-cast condition. The dendritic matrix is made up of pearlite, ferrite, and the interdendritic eutectic boride is with a chemical formula of M2B (...

  6. Advanced powder metallurgy aluminum alloys via rapid solidification technology

    Science.gov (United States)

    Ray, R.

    1984-01-01

    Aluminum alloys containing 10 to 11.5 wt. pct. of iron and 1.5 to 3 wt. pct. of chromium using the technique of rapid solidification powder metallurgy were studied. Alloys were prepared as thin ribbons (.002 inch thick) rapidly solidified at uniform rate of 10(6) C/second by the melt spinning process. The melt spun ribbons were pulverized into powders (-60 to 400 mesh) by a rotating hammer mill. The powders were consolidated by hot extrusion at a high reduction ratio of 50:1. The powder extrusion temperature was varied to determine the range of desirable processing conditions necessary to yield useful properties. Powders and consolidated alloys were characterized by SEM and optical metallography. The consolidated alloys were evaluated for (1) thermal stability, (2) tensile properties in the range, room temperature to 450 F, and (3) notch toughness in the range, room temperature to 450 F.

  7. Laser treatment of aluminum copper alloys: A mechanical enhancement

    International Nuclear Information System (INIS)

    Aluminum-copper alloys are commonly used as structural components for the car and aircraft industry. They combine low density, high strength, high fracture toughness and good machinability. Moreover, the strength and wear-resistance of the surface of alloys are improved by a high power laser beam. In this way the molten surface will be self-quenched by conduction of heat into the bulk. This technique ensures solidification velocities of 0.01--1 m/s. These high solidification velocities have a significant influence on the size and distribution of the morphology. This work concentrates on Al-Cu alloys, in which the Cu content ranges between 0--40 wt.%, and is aimed at describing the mechanical and microstructural properties of these alloys upon variation of the laser scan velocity in the range of 0.0125 to 0.125 m/s

  8. A Study on the Microstructures and Toughness of Fe-B Cast Alloy Containing Rare Earth

    Science.gov (United States)

    Yi, Dawei; Zhang, Zhiyun; Fu, Hanguang; Yang, Chengyan; Ma, Shengqiang; Li, Yefei

    2015-02-01

    This study investigates the effect of cerium on the microstructures, mechanical properties of medium carbon Fe-B cast alloy. The as-cast microstructure of Fe-B cast alloy consists of the eutectic boride, pearlite, and ferrite. Compared with the coarse eutectic borides in the unmodified alloy, the eutectic boride structures in the modified alloy are greatly refined. Cerium promotes the formation of Ce2O3 phase. Ce2O3 can act as effective heterogeneous nuclei of primary austenite, and refine austenite and boride. After heat treatment, the impact toughness of the modified alloy is higher than that of the unmodified alloy because there are more broken borides in the modified alloy. Meanwhile, the fracture mechanism of medium carbon Fe-B alloy is depicted and analyzed by using fractography.

  9. Structural analysis of heat treated automotive cast alloy

    Directory of Open Access Journals (Sweden)

    E. Tillová

    2011-07-01

    Full Text Available Purpose: The present study is conducted to investigate and to provide a better understanding of the heat treatment T4 (solution treatment at 505, 515 and 525°C, holding time 2, 4, 8,16 and 32 hours, then quenching in warm water in the range from 40°C and natural aging at room temperature during 24 hours on the microstructure (morphology of eutectic Si, morphology of intermetallic Fe- and Cu-rich phases and on mechanical properties (tensile strength and Brinell hardness of recycled (secondary AlSi9Cu3 cast alloy.Design/methodology/approach: Metallographic samples were selected from tensile specimens (after testing and prepared by standard metallographic procedures (wet ground, polished with diamond pastes, finally polished with commercial fine silica slurry (STRUERS OP-U and etched by Dix-Keller, HNO3 or H2SO4 (standard etching or HCl (deep etching in order to reveal the three-dimensional morphology of phases. The microstructure was studied using an optical microscope Neophot 32 and SEM observation with EDX analysis using scanning electron microscope VEGA LMU II linked to the energy dispersive X-ray spectroscopy (EDX analyser Brucker Quantax. Hardness measurement was performed by a Brinell hardness tester with a load of 62.5 kp (1 kp = 9.807 N, 2.5 mm diameter ball and a dwell time of 15 s.Findings: The results indicate that increasing solution treatment temperature results in spheroidization of eutectic Si, gradual disintegration of iron rich intermetallic phases on base Al15(FeMn3Si2, dissolution but also melting of intermetallic phases on base Al-Al2Cu-Si. Optimal solution treatment (515°C/4 hours most improves mechanical properties. Further increases of solution time, leads to alloy elongations, while both, the tensile strength continuously drop.Practical implications: The present study is a part of larger research project, which was conducted to investigate and to provide a better understanding microstructure, heat treatment and

  10. Inference of optimal speed for sound centrifugal casting of Al-12Si alloys

    Science.gov (United States)

    Agari, Shailesh Rao; Mukunda, P. G.; Rao, Shrikantha S.; Sudhakar, K. G.

    2011-05-01

    True centrifugal casting is a standard casting technique for the manufacture of hollow, intricate and sound castings without the use of cores. The molten metal or alloy poured into the rotating mold forms a hollow casting as the centrifugal forces lift the liquid along the mold inner surface. When a mold is rotated at low and very high speeds defects are found in the final castings. Obtaining the critical speed for sound castings should not be a matter of guess or based on experience. The defects in the casting are mainly due to the behavior of the molten metal during the teeming and solidification process. Motion of molten metal at various speeds and its effect during casting are addressed in this paper. Eutectic Al-12Si alloy is taken as an experiment fluid and its performance during various rotational speeds is discussed.

  11. The abrasive wear behaviour of alloy cast steel in SiC-water slurry

    Directory of Open Access Journals (Sweden)

    R. Zapała

    2009-10-01

    Full Text Available The results of abrasive wear tests carried out in an environment of SiC-water slurry on four grades of cast steel, i.e. carbon cast steel with microadditions of vanadium, low-alloy L70H2GNM cast steel, and high-alloy L120G13 cast steels, without and with microadditions of vanadium, were discussed. Tests were carried out on a Miller machine. A measure of the abrasive wear resistance was the loss of mass in specimens during 16 hour test cycle. It has been proved that the L120G13 cast steel is definitely less resistant to abrasive wear than its L70H2GNM counterpart. On the other hand, no distinct differences in the abrasive wear resistance were noticed between the L120G13 cast steel without vanadium, and the L120G13 cast steel and carbon cast steel, both with microadditions of vanadium.

  12. Investigation of the Precipitation Behavior in Aluminum Based Alloys

    KAUST Repository

    Khushaim, Muna S.

    2015-11-30

    The transportation industries are constantly striving to achieve minimum weight to cut fuel consumption and improve overall performance. Different innovative design strategies have been placed and directed toward weight saving combined with good mechanical behavior. Among different materials, aluminum-based alloys play a key role in modern engineering and are widely used in construction components because of their light weight and superior mechanical properties. Introduction of different nano-structure features can improve the service and the physical properties of such alloys. For intelligent microstructure design in the complex Al-based alloy, it is important to gain a deep physical understanding of the correlation between the microstructure and macroscopic properties, and thus atom probe tomography with its exceptional capabilities of spatially resolution and quantitative chemical analyses is presented as a sophisticated analytical tool to elucidate the underlying process of precipitation phenomena in aluminum alloys. A complete study examining the influence of common industrial heat treatment on the precipitation kinetics and phase transformations of complex aluminum alloy is performed. The qualitative evaluation results of the precipitation kinetics and phase transformation as functions of the heat treatment conditions are translated to engineer a complex aluminum alloy. The study demonstrates the ability to construct a robust microstructure with an excellent hardness behavior by applying a low-energy-consumption, cost-effective method. The proposed strategy to engineer complex aluminum alloys is based on both mechanical strategy and intelligent microstructural design. An intelligent microstructural design requires an investigation of the different strengthen phases, such as T1 (Al2CuLi), θ′(Al2Cu), β′(Al3Zr) and δ′(Al3Li). Therefore, the early stage of phase decomposition is examined in different binary Al-Li and Al-Cu alloys together with different

  13. Fatigue crack propagation of new aluminum lithium alloy bonded with titanium alloy strap

    Institute of Scientific and Technical Information of China (English)

    Sun Zhenqi; Huang Minghui

    2013-01-01

    A new type of aluminum lithium alloy (A1-Li alloy) Al-Li-S-4 was investigated by test in this paper.Alloy plate of 400 mm × 140 mm × 6 mm with single edge notch was made into samples bonded with Ti-6Al-4V alloy (Ti alloy) strap by FM 94 film adhesive after the surface was treated.Fatigue crack growth of samples was investigated under cyclic loading with stress ratio (R) of 0.1 and load amplitude constant.The results show that Al-Li alloy plate bonded with Ti alloy strap could retard fatigue crack propagation.Retardation effect is related with width and thickness of strap.Flaws have an observable effect on crack propagation direction.

  14. Research of Plasma Spraying Process on Aluminum-Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    Patricija Kavaliauskaitė

    2016-04-01

    Full Text Available The article examines plasma sprayed 95Ni-5Al coatings on alu-minum-magnesium (Mg ≈ 2,6‒3,6 % alloy substrate. Alumi-num-magnesium samples prior spraying were prepared with mechanical treatment (blasting with Al2O3. 95Ni-5Al coatings on aluminum-magnesium alloys were sprayed with different parameters of process and coating‘s thickness, porosity, micro-hardness and microstructure were evaluated. Also numerical simulations in electric and magnetic phenomena of plasma spray-ing were carried out.

  15. Cracking susceptibility of aluminum alloys during laser welding

    Directory of Open Access Journals (Sweden)

    Lara Abbaschian

    2003-06-01

    Full Text Available The influence of laser parameters in welding aluminum alloys was studied in order to reduce hot cracking. The extension of cracks at the welding surface was used as a cracking susceptibility (CS index. It has been shown that the CS changes with changing welding velocity for binary Al-Cu alloys. In general, the CS index increased until a maximum velocity and then dropped to zero, generating a typical lambda-curve. This curve is due to two different mechanisms: 1 the refinement of porosities with increasing velocity and 2 the changes in the liquid fraction due to decreasing microsegregation with increasing velocities.

  16. 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 ...

  17. Characterization of pores in high pressure die cast aluminum using active thermography and computed tomography

    Science.gov (United States)

    Maierhofer, Christiane; Myrach, Philipp; Röllig, Mathias; Jonietz, Florian; Illerhaus, Bernhard; Meinel, Dietmar; Richter, Uwe; Miksche, Ronald

    2016-02-01

    Larger high pressure die castings (HPDC) and decreasing wall thicknesses are raising the issue of casting defects like pores in aluminum structures. Properties of components are often strongly influenced by inner porosity. As these products are being established more and more in lightweight construction (e.g. automotive and other transport areas), non-destructive testing methods, which can be applied fast and on-site, are required for quality assurance. In this contribution, the application of active thermography for the direct detection of larger pores is demonstrated. The analysis of limits and accuracy of the method are completed by numerical simulation and the method is validated using computed tomography.

  18. Plasma spraying of beryllium and beryllium-aluminum-silver alloys

    International Nuclear Information System (INIS)

    A preliminary investigation on plasma-spraying of beryllium and a beryllium-aluminum 4% silver alloy was done at the Los Alamos National Laboratory's Beryllium Atomization and Thermal Spray Facility (BATSF). Spherical Be and Be-Al-4%Ag powders, which were produced by centrifugal atomization, were used as feedstock material for plasma-spraying. The spherical morphology of the powders allowed for better feeding of fine (<38 μm) powders into the plasma-spray torch. The difference in the as-deposited densities and deposit efficiencies of the two plasma-sprayed powders will be discussed along with the effect of processing parameters on the as-deposited microstructure of the Be-Al-4%Ag. This investigation represents ongoing research to develop and characterize plasma-spraying of beryllium and beryllium-aluminum alloys for magnetic fusion and aerospace applications

  19. Influence of additives on the microstructure and tensile properties of near-eutectic Al-10.8%Si cast alloy

    International Nuclear Information System (INIS)

    The continuing quest for aluminum castings with enhanced mechanical properties for applications in the automotive industries has intensified the interest in aluminum-silicon alloys. In Al-Si alloys, the properties are influenced by the shape and distribution of the eutectic silicon particles in the matrix, as also by the iron intermetallics and copper phases that occur upon solidification. The detailed microstructure and tensile properties of as-cast and heat-treated new experimental alloy belonging to cast Al-Si near-eutectic alloys have been investigated as a function of Fe, Mn, Cu, and Mg content. Microstructural examination was carried out using optical microscopy, image analysis, and electron probe microanalysis (EPMA), wavelength dispersive spectroscopic (WDS) analysis facilities. Tensile properties upon artificial aging in the temperature range of 155-240 oC for 5 h were also investigated. The results show that the volume fraction of Fe-intermetallics increases as the iron or manganese contents increase. Compact polygonal or star-like particles form when the sludge factor is greater than 2.1. The Al2Cu phase was observed to dissolve almost completely during solution heat treatment of all the alloys studied, especially those containing high levels of Mg and Fe, while Al5Cu2Mg8Si6, sludge, and α-Fe phases were found to persist after solution heat treatment. The β-Al5(Fe,Mn)Si phase dissolved partially in Sr-modified alloys, and its dissolution became more pronounced after solution heat treatment. At 0.5% Mn, the β-Fe phase forms when the Fe content is above 0.75%, causing the tensile properties to decrease drastically. The same results are obtained when the levels of both Fe and Mn are increased beyond 0.75%, because of sludge formation. On the other hand, the tensile properties of the Cu-containing alloys are affected slightly at high levels of Mg as a result of the formation of Al5Cu2Mg8Si6 which decreases the amount of free Mg available to form the Al2Cu

  20. Modelling of mechanical properties of Al-Si-Cu cast alloys using the neural network

    OpenAIRE

    M. Krupiński; J.H. Sokolowski; R. Maniara; L.A. Dobrzański

    2007-01-01

    Purpose: The paper presents some results of the research connected with the development of new approach basedon the neural network to predict the chemical composition and cooling rate to the mechanical properties of Al–Si–Cu cast alloys. The independent variables in the model are chemical composition of Al–Si–Cu cast alloys andcooling rate. The dependent parameters are hardness, microhardess, yield strength and apparent elastic limit.Design/methodology/approach: The experimental alloy used fo...

  1. Experimental Studies of Cold Roll Bonded Aluminum Alloys

    OpenAIRE

    Lauvdal, Steinar

    2011-01-01

    This master’s thesis is based on experimental studies of the parameters influencing cold roll bonding (CRB) of the aluminum alloys AA1200 and AA3103,in the work hardened and annealed condition. The effect on the bond strength from the preparations parameters as degreasing agent, scratch brushing and exposure time for oxide growth is investigated in comparison to former studies. Further the effect of rolling speed and effect from contributing factors from the different testing methods is ...

  2. Linear Anomaly in Welded 2219-T87 Aluminum Alloy

    Science.gov (United States)

    Jemian, Wartan A.

    1987-01-01

    Study of causes and significance of two types of linear anomalies sometimes appearing in radiographs of welds described in preliminary report. Manifested as light or dark linear features parallel to weld line in radiograph of weld. Contains diagrams and descriptions of phenomena occurring during welding process. Includes microdensitometer traces from x-radiographs of actual welds and from computer simulations based calculation of x-ray transmission through assumed weld structures. Concludes anomalies not unique to 2219-T87 aluminum alloy.

  3. Residual stress profiling of an aluminum alloy by laser ultrasonics

    Institute of Scientific and Technical Information of China (English)

    PAN Yondong; QIAN Menglu; XU Weijiang; M. OURAK

    2004-01-01

    A residual-stress profile along the thickness of an aluminum alloy sheet is determined by laser-ultrasonic technique. Surface acoustic waves are generated by a Nd:YAG pulse laser and detected by a Heterodyne interferometer on a lateral free surface of the sheet. The distribution of residual stress is determined by measuring the relative variation of the wavevelocities at different location of the sample along its thickness. This technique is validated by three different residual stress profiles obtained experimentally.

  4. Residual stress in quenched 7075 aluminum alloy thick plates

    Institute of Scientific and Technical Information of China (English)

    林高用; 张辉; 朱伟; 彭大暑; 梁轩; 周鸿章

    2003-01-01

    The influence of quenching water temperature, pre-stretching amount and aging temperature and times on residual stress in 7075 aluminum thick plate was studied by the measurement of residual stress using drilling hole method. The results indicate that residual stress decreases by 30% with increasing quenching water temperature from 40 ℃ to 80 ℃, 20% with increasing aging temperature from 100 ℃ to 180 ℃,and 20% with increasing aging times from 5 h to 25 h. Also, residual stress decreases to zero with increasing pre-stretching amount to approximately 2%. Hence, residual stress in 7075 aluminum thick plate is reduced by the control of quenching water temperature at 80 ℃ and with pre-stretching amount of about 2%. An optimal aging temperature and time should be systemically investigated to obtain combination of high mechanical performances and lower residual stress for manufacturing of 7075 aluminum alloy thick plates.

  5. An Influence of Ageing on the Structure, Corrosion Resistance and Hardness of High Aluminum ZnAl40Cu3 Alloy

    Directory of Open Access Journals (Sweden)

    Michalik R.

    2016-03-01

    Full Text Available Zn-Al-Cu alloys are used primarily because of their tribological properties as an alternative material for bronze, cast iron and aluminum alloy bearings and as a construction material. Particularly interesting are high aluminum zinc alloys. Monoeutectic zinc and aluminum alloys are characterized by the highest hardness, tensile strength and wear resistance of all of the zinc alloys. A significant problem with the use of the Zn-Al-Cu alloys is their insufficient resistance to electrochemical corrosion. Properties of Zn-Al-Cu alloys can be improved by heat treatment. The purpose of examination was to determine the effect of heat treatment (aging at various temperatures on the microstructure and corrosion resistance of the ZnAl40Cu3 alloy. The scope of the examination included: structural examinations, determination of hardness using Brinell’s method and corrosion resistance examinations. Ageing at higher temperatures causes a creation of areas where is an eutectoid mixture. The study showed that ageing causes a decrease in hardness of ZnAl40Cu3 alloy. This decrease is even greater, when the temperature of ageing is lower. The studies have shown a significant influence of ageing on the corrosion resistance of the alloy ZnAl40Cu3. Maximum corrosion resistance were characterized by the sample after ageing at higher temperatures.

  6. Microstructure and mechanical properties of aluminum alloy matrix composite reinforced with nano-particle MgO

    Energy Technology Data Exchange (ETDEWEB)

    Yar, A. Ansary, E-mail: arash_ansaryyar@yahoo.co [Department of Materials, Islamic Azad University, South Tehran Branch, P.O. Box 11365-4435, Tehran (Iran, Islamic Republic of); Montazerian, M.; Abdizadeh, H. [School of Metallurgy and Materials Engineering, University of Tehran, P.O. Box 11365-4563, Tehran (Iran, Islamic Republic of); Baharvandi, H.R. [Malek Ashtar University of Technology, P.O. Box 16765-3454, Tehran (Iran, Islamic Republic of)

    2009-09-18

    In this research, aluminum alloy (A356.1) matrix composites reinforced with 1.5, 2.5 and 5 vol% nano-particle MgO were fabricated via stir casting method. Fabrication was performed at various casting temperatures, viz. 800, 850 and 950 deg. C. Optimum amount of reinforcement and casting temperature were determined by evaluating the density, microstructure and mechanical properties of composites. The composites were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Hardness and compression tests were carried out in order to identify mechanical properties. The results reveal that the composites containing 1.5 vol% reinforcement particle fabricated at 850 deg. C have homogenous microstructure as well as improved mechanical properties.

  7. Effect of nanoparticles on the structure and properties of an aluminum alloy poured into a mould with the use of a magnetohydrodynamic disk pump

    Science.gov (United States)

    Katsnelson, S. S.; Pozdnyakov, G. A.; Cherepanov, A. N.

    2015-09-01

    The influence of two nanomodifiers with different compositions during their homogenization in the AL7 aluminum melt and moulding on the properties of the modified aluminum alloy is studied. Experiments are performed with the use of a centrifugal conductive magnetohydrodynamic pump. The melt is poured into a graphite mould with three cylindrical channels 38 mm in diameter and 160 mm long, which are designed for a metal mass of 500 g. Two compositions are used as modifying agents: nano-scale particles of the aluminum nitride powder 40-100 nm in size and metallized carbon nanotubes smaller than 25 nm, which are clad with aluminum to improve wetting of their surface. The analysis of the structure of the experimental and reference samples shows that the use of modifiers leads to refinement of the grain structure of the cast metal. According to the Hall-Petch theory, this effect may result in improvement of mechanical characteristics of the cast metal.

  8. Butt-welding Residual Stress of Heat Treatable Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    C.M. Cheng

    2007-01-01

    This study, taking three types of aluminum alloys 2024-T351, 6061-T6 and 7075-T6 as experimental materials, conducted single V-groove GTAW (gas tungsten arc welding) butt-welding to analyze and compare the magnitude and differences of residual stress in the three aluminum alloys at different single V-groove angles and in restrained or unrestrained conditions. The results show that the larger the grooving angle of butt joint, the higher the residual tensile stress. Too small grooving angle will lead to dramatic differences due to the amount of welding bead filler metal and pre-set joint geometry. Therefore, only an appropriate grooving angle can reduce residual stress. While welding, weldment in restrained condition will lead to a larger residual stress. Also, a residual stress will arise from the restraint position. The ultimate residual stress of weldment is determined by material yield strength at equilibrium temperature. The higher the yield strength at equilibrium temperature, the higher the material residual stress. Because of its larger thermal conductivity, aluminum alloy test specimens have small temperature differential. Therefore, the residual tensile stress of all materials is lower than their yield strength.

  9. Mold Materials For Permanent Molding of Aluminum Alloys

    Energy Technology Data Exchange (ETDEWEB)

    John F Wallace; David Schwam; Wen Hong dxs11@po.cwru.edu

    2001-09-14

    A test that involves immersion of the potential mod materials for permanent molds has been developed that provides a thermal cycle that is similar to the experienced during casting of aluminum in permanent molds. This test has been employed to determine the relative thermal fatigue resistance of several different types of mold materials. Four commercial mold coatings have been evaluated for their insulating ability, wear resistance and roughness. The results indicate that composition and structure of the mold materials have considerable effect on their thermal fatigue cracking behavior. Irons with a gray iron structure are the most prone to thermal fatigue cracking followed by compacted graphite irons with the least thermal fatigue cracking of the cast irons experienced by ductile iron. The composition of these various irons affects their behavior.

  10. Influence of Solid Fraction on Gravity Segregation of Sn in Al-20Sn Alloy Casting

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The influence of solid fraction of Al-20Sn alloy mushy on gravity segregation of Sn in casting was studied and, the relationship between solid fraction and the temperature of alloy mushy and that between solid fraction of alloy mushy and size of Sn particle in ingot were determined. The results show that the relationship between solid fraction and the temperature of alloy mushy was fs=1683-4.86t+0.0035t2. The extent of gravity segregation of Sn in casting reduced gradually with the increasing of solid fraction of alloy mushy. When solid fraction of alloy mushy was arger than 40%, the gravity segregation of Sn in casting could be removed basically, and the relationship between solid fraction of alloy mushy and size of Sn particle in ingot was s=-0.64fs+70.8.

  11. Silicon effects on formation of EPO oxide coatings on aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L. [Department of Mechanical, Automotive and Materials Engineering, University of Windsor, Windsor, ON, N9B 3P4 (Canada); Nie, X. [Department of Mechanical, Automotive and Materials Engineering, University of Windsor, Windsor, ON, N9B 3P4 (Canada)]. E-mail: xnie@uwindsor.ca

    2006-01-03

    Electrolytic plasma processes (EPP) can be used for cleaning, metal-coating, carburizing, nitriding, and oxidizing. Electrolytic plasma oxidizing (EPO) is an advanced technique to deposit thick and hard ceramic coatings on a number of aluminum alloys. However, the EPO treatment on Al-Si alloys with a high Si content has rarely been reported. In this research, an investigation was conducted to clarify the effects of silicon contents on the EPO coating formation, morphology, and composition. Cast hypereutectic 390 alloys ({approx} 17% Si) and hypoeutectic 319 alloys ({approx} 7% Si) were chosen as substrates. The coating morphology, composition, and microstructure of the EPO coatings on those substrates were investigated using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). A stylus roughness tester was used for surface roughness measurement. It was found that the EPO process had four stages where each stage was corresponding to various coating surface morphology, composition, and phase structures, characterised by different coating growth mechanisms.

  12. Solidification crack susceptibility of aluminum alloy weld metals

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The susceptibilities of the three aluminum alloys to solidification crack were studied with trans-varestraint tests and tensile tests at elevated temperature. Their metallurgical characteristics, morphologies of the fractured surface and dynamic cracking behaviors at elevated temperature were analyzed with a series of micro-analysis methods. The results show that dynamic cracking models can be classified into three types. The first model has the healing effect which is called type A. The second is the one with deformation and breaking down of metal bridge, called type B. The last one is with the separation of liquid film along grain boundary, called type C.Moreover, the strain rate has different effects on crack susceptibility of aluminum alloys with different cracking models. ZL101 and 5083 alloys belong to type A and type C cracking model respectively, in which strain rate has greater effect on eutectic healing and plastic deformation of metal bridge. 6082 alloy is type B cracking model in which the strain rate has little effect on the deformation ability of the liquid film.

  13. The characteristics of aluminum-scandium alloys processed by ECAP

    International Nuclear Information System (INIS)

    Aluminum-scandium alloys were prepared having different scandium additions of 0.2, 1.0 and 2.0 wt.% and these alloys were processed by equal-channel angular pressing (ECAP) at 473 K. The results show the grain refinement of the aluminum matrix and the morphology of the Al3Sc precipitates depends strongly on the scandium concentration. The tensile properties were evaluated after ECAP by pulling to failure at initial strain rates from 1.0 x 10-3 to 1.0 x 10-1 s-1. The Al-1% Sc alloy exhibited the highest tensile strength of ∼250 MPa at a strain rate of 1.0 x 10-1 s-1. This alloy also exhibited a superior grain refinement of ∼0.4 μm after ECAP where this is attributed to a smaller initial grain size and an optimum volume fraction of dispersed Al3Sc precipitates having both micrometer and nanometer sizes.

  14. In-situ processing of aluminum nitride particle reinforced aluminum alloy composites

    Science.gov (United States)

    Zheng, Qingjun

    Discontinuously reinforced aluminum alloy composites (DRACs) have potential applications in automotive, electronic packaging, and recreation industries. Conventional processing of DRACs is by incorporation of ceramic particles/whiskers/fibers into matrix alloys. Because of the high cost of ceramic particles, DRACs are expensive. The goal of this work was to develop a low-cost route of AlN-Al DRACs processing through bubbling and reacting nitrogen and ammonia gases with aluminum alloy melt in the temperature range of 1373--1523 K. Thermodynamic analysis of AlN-Al alloy system was performed based on Gibbs energy minimization theory. AlN is stable in aluminum, Al-Mg, Al-Si, Al-Zn, and Al-Li alloys over the whole temperature range for application and processing of DRACs. Experiments were carried out to form AlN by bubbling nitrogen and ammonia gases through aluminum, Al-Mg, and Al-Si alloy melts. Products were characterized with XRD, SEM, and EDX. The results showed that in-situ processing of AlN reinforced DRACs is technically feasible. Significant AlN was synthesized by bubbling deoxidized nitrogen and ammonia gases. When nitrogen gas was used as the nitrogen precursor, the AlN particles formed in-situ are small in size, (interface. In comparison with nitrogen gas, bubbling ammonia led to formation of AlN particles in smaller size (about 2 mum or less) at a significantly higher rate. Ammonia is not stable and dissociated into nitrogen and hydrogen at reaction temperatures. The hydrogen functions as oxygen-getter at the interface and benefits chemisorption of nitrogen, thereby promoting the formation of AlN. The overall process of AlN formation was modeled using two-film model. For nitrogen bubbling gas, the whole process is controlled by chemisorption of nitrogen molecules at the gas bubble - aluminum melt interface. For ammonia precursor, the rate of the overall process is limited by the mass transfer of nitrogen atoms in the liquid boundary layer. The models agree

  15. Electrorefining of aluminum alloy in ionic liquids at low temperatures

    Directory of Open Access Journals (Sweden)

    Kamavaram V.

    2003-01-01

    Full Text Available The electrorefining of aluminum alloy (A360 in ionic liquids at low temperatures has been investigated. The ionic liquid electrolyte was prepared by mixing anhydrous AlCl3 and 1-Butyl-3- methylimidazolium chloride (BMIC in appropriate proportions. The effect of the cell voltage temperature, and the composition of the electrolyte on the electrorefining process has been studied. The characterization of the deposited aluminum was performed using scanning electron microscopy (SEM and X-ray diffraction (XRD techniques. The influence of experimental parameters such as cell voltage and concentration of AlCl3 in the electrolyte on the deposit morphology was discussed. The composition of the aluminum deposits was analyzed using X-ray fluorescence spectrometer (XRF. Aluminum deposits with purity higher than 99.89 % were obtained. At a cell voltage of 1.0 V vs. Al/Al(III, the energy consumption was about 3 kWh/kg-Al. The main advantage of the process is low energy consumption compared to the existing industrial aluminum refining process.

  16. The stamping behavior of an early-aged 6061 aluminum alloy

    International Nuclear Information System (INIS)

    Highlights: → Excellent stamping performance of 6061 aluminum alloy. → Improvement of stamping behavior of 6061 aluminum alloy by early-aging. → Observation of dislocations and precipitates using Weak-Beam Dark-Field technique. -- Abstract: The stamping behavior of 6061 aluminum alloy with various conditions of early-aging is investigated in the present study. The relationship between the stamping performance, microstructure and mechanical property for this alloy is also discussed. Experimental results show that the 6061 aluminum alloy with a 10-30 min. early-aging at 160 oC will exhibit excellent stamping performance. The burnished surface of these treated alloys can reach a quite high value of 47%. Meanwhile, the mechanical strength and impact toughness have important effects on the stamping behavior of 6061 aluminum alloy. The moderate values of mechanical strength and toughness will exhibit an optimal stamping performance.

  17. Enhancement of superplastic formability in a high strength aluminum alloy

    Science.gov (United States)

    Agrawal, S. P.; Turk, G. R.; Vastava, R.

    1988-01-01

    A 7475 aluminum alloy was developed for superplastic forming (SPF). By lowering the Fe and Si contents in this alloy significantly below their normal levels and optimizing the thermomechanical processing to produce sheet, over 2000 percent thickness strain to failure was obtained. The microstructure, elevated-temperature uniaxial and biaxial tension, and cavitation behavior of the alloy were determined. In addition, a constitutive model was used to form a generic structural shape from which mechanical test specimens were removed and post-SPF characteristics were evaluated. The constitutive model included both material strain hardening and strain rate hardening effects, and was verified by accurately predicting forming cycles which resulted in successful component forming. Stress-life fatigue, stress rupture, and room and elevated temperature tensile tests were conducted on the formed material.

  18. Mechanical properties of hot rolled 2519 aluminum alloy plate

    Institute of Scientific and Technical Information of China (English)

    彭大暑; 陈险峰; 林启权; 张辉

    2003-01-01

    The effects of differences of temper on mechanical properties of T6, T7 and T8 plates of aluminum alloy 2519 were studied. The stress corrosion cracking(SCC) sensitivity was evaluated with parameters such as Kσ and Kδ.Tensile tests were divided into two groups: one was performed on tensile specimens without pre-corrosion, the other was performed on tensile specimens which were pre-corroded in 3.5%NaCl+1%H2O2 solution at 25 ℃.The results show that SCC resistance of alloy 2519 ranks in the order of T8>T7>T6 and the mechanical properties rank in the order of T6>T8>T7. SEM fractographs of the failed specimen show that the SCC sensitivity can be determined by the distribution of the second phase particles and size and the shape of grains in the alloy.

  19. Effects of shot peening on internal friction in CP aluminum and aluminum alloy 6008

    Energy Technology Data Exchange (ETDEWEB)

    Flejszar, Aneta; Ludian, Tomasz; Mielczarek, Agnieszka; Riehemann, Werner; Wagner, Lothar [Clausthal Univ. of Science and Technology, Inst. of Materials Science and Technology, Clausthal-Zellerfeld (Germany)

    2009-06-15

    The strain-amplitude-dependent damping of bending beams of aluminum alloy 6008 and CP aluminum was measured at room temperature after different heat treatments and after shot peening. Shot peening led to an increase of damping in almost the whole measured amplitude strain range from 10{sup -6} to 10{sup -3} for CP aluminum. Strong ageing effects at room temperature were observed immediately after the shot peening process, namely an increase of the amplitude dependent part and a decrease of the amplitude-independent part of damping. After about 2700 h, ageing of the samples had saturated. For aluminum alloy 6008 much smaller ageing effects were found being due to compensating effects like formation of Cottrell clouds, precipitation of G.P. - zones, and the reduction of foreign atoms in solid solution. The found amplitude-dependent damping can be explained by the reversible movement of dislocations between strong pinning points like, e.g., precipitates and weak pinning points like solid solute atoms as proposed by the dislocation damping theory of Granato and Luecke. Using this model the found ageing effects can be explained by the diffusion of solid solute atoms to the dislocations. (orig.)

  20. Radiation Damages in Aluminum Alloy SAV-1 under Neutron Irradiation

    Science.gov (United States)

    Salikhbaev, Umar; Akhmedzhanov, Farkhad; Alikulov, Sherali; Baytelesov, Sapar; Boltabaev, Azizbek

    2016-05-01

    The aim of this work was to study the effect of neutron irradiation on the kinetics of radiation damages in the SAV-1 alloy, which belongs to the group of aluminum alloys of the ternary system Al-Mg-Si. For fast-neutron irradiation by different doses up to fluence 1019 cm-2 the SAV-1 samples were placed in one of the vertical channels of the research WWR type reactor (Tashkent). The temperature dependence of the electrical resistance of the alloy samples was investigated in the range 290 - 490 K by the four-compensation method with an error about 0.1%. The experimental results were shown that at all the temperatures the dependence of the SAV-1 alloy resistivity on neutron fluence was nonlinear. With increasing neutron fluence the deviation from linearity and the growth rate of resistivity with temperature becomes more appreciable. The observed dependences are explained by means of martensitic transformations and the radiation damages in the studied alloy under neutron irradiation. The mechanisms of radiation modification of the SAV-1 alloy structure are discussed.

  1. Dilution of molybdenum on aluminum during laser surface alloying

    International Nuclear Information System (INIS)

    Highlights: •Laser surface alloying significantly increased the solubility of transition metal. •Laser surface alloying produced dense coating with good metallurgical bonding. •Laser process parameters greatly influenced the evolution of various intermetallics. •Computationally predicted results closely matched with experimental findings. •Ability to generalize present model to other metal-transition metal systems. -- Abstract: A multiphysics based computational model was developed to predict the dilution of molybdenum (Mo) on an aluminum (Al) substrate during the laser surface alloying process. The influence of laser surface alloying processing parameters such as input energy, scanning speed, and overlapping ratio on dilution of Mo in Al was explored via computational model. The computational model, closely predicts the melt pool geometry (width and depth) that subsequently helps in estimating dilution. It was observed that the dilution increases with the increase in laser power, while it decreases with the increase in scanning speed. The phase and microstructural analyses revealed the existence of Al5Mo intermetallic for most of the laser surface alloying processing conditions. However, at higher (3.18 × 107 J/m2) and lower (1.91 × 107 J/m2) laser energy densities, the Al8Mo3 intermetallic was also evolved. These experimental observations validate the model’s predictions and points to its reliability in predicting the expected intermetallics in Al–Mo system for various laser surfacing alloying processing conditions

  2. The effect of cast-to-cast variations on the quality of thin section nickel alloy welded joints

    International Nuclear Information System (INIS)

    The welding behaviour of 26 commercial casts of Alloy 800 has been quantified for mechanised, autogenous, full penetration, bead-on-strip tungsten inert gas welding tests. Weld front and back widths have been measured and correlated with minor element variations. Casts with similar welding responses have been sorted into groups. The behaviour of the weld pool, surface slags and arc have been compared and a convection controlled model has been used to account for differences between the groups of casts. The main factors governing laboratory process control variability have been identified and a statistical method has been used to identify all the components of weld variance. An optimum size of welding test matrix has been proposed to determine typical cast-to-cast variations at high significance levels. (author)

  3. Influence of the casting processing route on the corrosion behavior of dental alloys.

    Science.gov (United States)

    Galo, Rodrigo; Rocha, Luis Augusto; Faria, Adriana Claudia; Silveira, Renata Rodrigues; Ribeiro, Ricardo Faria; de Mattos, Maria da Gloria Chiarello

    2014-12-01

    Casting in the presence of oxygen may result in an improvement of the corrosion performance of most alloys. However, the effect of corrosion on the casting without oxygen for dental materials remains unknown. The aim of this study was to investigate the influence of the casting technique and atmosphere (argon or oxygen) on the corrosion behavior response of six different dental casting alloys. The corrosion behavior was evaluated by electrochemical measurements performed in artificial saliva for the different alloys cast in two different conditions: arc melting in argon and oxygen-gas flame centrifugal casting. A slight decrease in open-circuit potential for most alloys was observed during immersion, meaning that the corrosion tendency of the materials increases due to the contact with the solution. Exceptions were the Co-based alloys prepared by plasma, and the Co-Cr-Mo and Ni-Cr-4Ti alloys processed by oxidized flame, in which an increase in potential was observed. The amount of metallic ions released into the artificial saliva solution during immersion was similar for all specimens. Considering the pitting potential, a parameter of high importance when considering the fluctuating conditions of the oral environment, Co-based alloys show the best performance in comparison with the Ni-based alloys, independent of the processing route. PMID:25491859

  4. Technology of the multifunctional protective coating production with the superficial alloying in a casting form

    Directory of Open Access Journals (Sweden)

    Abacharaev Ibrahim Musaevitch

    2010-04-01

    Full Text Available The investigations of production of thick chromium-carbide coatings are made on steel 40L and grey cast iron SCH25 with application of alloying pastes on the working surfaces of the casting forms. It is determined that alloying in a casting form of steel 40L and cast-iron SCH25 become effective in the pro-duction of chromium-carbide layers with thickness 120–240 mkm and increase their cavitation resistance by 10–12 and 20–25 times accordingly.

  5. From 2007 to 2010,China Will Manufacture More Than 10,000 Aluminum Alloy Railcars

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>The clear advantage of the aluminum alloy rail- cars is the weight reduction.The deadweight of the aluminum alloy railcars usually does not exceed 8.5t each.The 52 motor train units used in the sixth nationwide railway speedup are all made of aluminum alloys except for the train units used in the line between Guangzhou and Shenzhen.It is estimated that in 2010,there are more than 10,000 railcars made of aluminum alloys,which will consume about 105kt alumi- num.

  6. Effect of vapor phase corrosion inhibitor on microbial corrosion of aluminum alloys.

    Science.gov (United States)

    Yang, S S; Ku, C H; Bor, H J; Lin, Y T

    1996-02-01

    Vapor phase corrosion inhibitors were used to investigate the antimicrobial activities and anticorrosion of aluminum alloy. Aspergillus flavus, A. niger, A. versicolor, Chaetomium globosum and Penicillium funiculosum had moderate to abundant growth on the aluminum alloy AA 1100 at Aw 0.901, while there was less growth at Aw 0.842. High humidity stimulated microbial growth and induced microbial corrosion. Dicyclohexylammonium carbonate had a high inhibitory effect on the growth of test fungi and the microbial corrosion of aluminum alloy, dicyclohexylammonium caprate and dicyclohexylammonium stearate were the next. Aluminum alloy coating with vapor phase corrosion inhibitor could prevent microbial growth and retard microbial corrosion. PMID:10592784

  7. Properties of Dispersion Casting of Y2O3 Particles in Hypo, Hyper and Eutectic Binary Al-Cu Alloys

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In the present work, the dispersion casting of Y2O3 particles in aluminum-copper alloy was investigated in terms of microstructural changes with respect to Cu contents of 20 (hypo), 33 (eutectic) and 40 (hyper)wt pct by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). For the fabrication of Al-Cu alloy dispersed Y2O3 ceramic particles, stir casting method was employed. In case of Al-20 wt pct Cu alloy (hypoeutectic), SEM images revealed that primary Al was grown up in the beginning. After that, eutectic phase with well dispersed ceramic particles was formed. In case of eutectic composition, Y2O3 particles were uniformly dispersed in the matrix. When the Cu is added into Al up to 40 wt pct (hypereutectic), primary θ phase was grown up without any Y2O3 ceramic particles in the early stage of solidification. Thereafter,eutectic phase was formed with well dispersed ceramic particles. It can be concluded that Y2O3 ceramic particles is mostly dispersed in case of eutectic composition in Al-Cu alloy.

  8. Metallurgical Mechanisms Controlling Mechanical Properties of Aluminum Alloy 2219 Produced by Electron Beam Freeform Fabrication

    Science.gov (United States)

    Domack, Marcia S.; Tainger, Karen M.

    2006-01-01

    The electron beam freeform fabrication (EBF3) layer-additive manufacturing process has been developed to directly fabricate complex geometry components. EBF3 introduces metal wire into a molten pool created on the surface of a substrate by a focused electron beam. Part geometry is achieved by translating the substrate with respect to the beam to build the part one layer at a time. Tensile properties demonstrated for electron beam deposited aluminum and titanium alloys are comparable to wrought products, although the microstructures of the deposits exhibit cast features. Understanding the metallurgical mechanisms controlling mechanical properties is essential to maximizing application of the EBF3 process. Tensile mechanical properties and microstructures were examined for aluminum alloy 2219 fabricated over a range of EBF3 process variables. Unique microstructures were observed within the deposited layers and at interlayer boundaries, which varied within the deposit height due to microstructural evolution associated with the complex thermal history experienced during subsequent layer deposition. Microstructures exhibited irregularly shaped grains with interior dendritic structures, described based on overall grain size, morphology, distribution, and dendrite spacing, and were correlated with deposition parameters. Fracture features were compared with microstructural elements to define fracture paths and aid in definition of basic processing-microstructure-property correlations.

  9. PROCESS CAPABILITY STUDY OF A RAPID CASTING SOLUTION FOR ALUMINIUM ALLOYS USING THREE-DIMENSIONAL PRINTING

    Directory of Open Access Journals (Sweden)

    R. Singh

    2011-12-01

    Full Text Available In the present work, the best shell wall thickness of a mould cavity was investigated in a process capability study of a rapid casting solution for aluminium alloys using three-dimensional printing (3DP. Starting from the identification of a component/benchmark, an aluminium-alloy casting prototype was produced with different shell wall thicknesses by three dimensional printing. The results of the study suggest that, at the best shell wall thickness (5 mm for aluminium alloys, the rapid casting solution using a 3DP process lies within the ±3.999 sigma (σ limit.

  10. Corrosion Behavior of the As-cast and Heat-treated ZA27 Alloy

    OpenAIRE

    B. Bobic; Mitrovic, S.; M. Babic; A. Vencl; I. Bobic

    2011-01-01

    Corrosion behaviour of the as-cast and heat-treated ZA27 alloy was examined. The alloy was prepared by conventional melting and casting route and then thermally processed by applying T4 heat treatment regime (solutionizing at 370 °C for 3 hours followed by water quenching and natural aging). Corrosion rate of the as-cast and heat-treated ZA27 alloy was determined in 3.5 wt. % NaCl solution through immersion test using both weight loss method and polarization resistance measurements. It was sh...

  11. The effect of thermohydrogen treatment on the structure and properties of casts obtained from titanium alloys

    International Nuclear Information System (INIS)

    The method based on the combination of high temperature gas-static and thermal hydrogen treatments is suggested to increase mechanical properties of cast pseudo-α and (α+β)-titanium alloys. The study is carried out using alloys VT20L, VT23L and alloy Ti-6%Al-2%Mo-4%Zr-2%Sn. It is shown that the method proposed provides the change in a cast structure, an increase in density of castings, an increase of strength properties by 10-20% and fatigue by a factor of 1.5-2 at satisfactory ductility and impact strength

  12. 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

  13. Influence of Technical Parameters on the Properties of Micro-arc Oxidation Film on Casted Aluminum-Silicon Alloy%工艺参数对铸造铝-硅合金微弧氧化层特性的影响

    Institute of Scientific and Technical Information of China (English)

    卢立红; 沈德久; 王玉林

    2001-01-01

    Ceramic coating was obtained by micro-arc oxidation on thesubstrate of casted aluminum-silicon alloy. The influence of current density and intensifying time on the thickness, the surface roughness and the hardness of the ceramic layer, and the influence of intensifying time on the forming velocity of the layer are studied in this paper. The results show that both the thickness and the surface roughness of the layer increase. There is a limit value in the thickenss with the increase in current density and intensifying time. The hardness increases and there is a limit value with the increase in the current density. In lower current density, the forming velocity of the ceramic layer does not vary with the intensifying time, while it decreases with the increment of intensifying time in higher current density, and its value approximates zero in the end. The higher the current density is, the faster the decrease of forming velocity.%用微弧氧化的方法在铸造铝-硅合金基体上获得陶瓷层。分别研究了电流密度及强化时间对陶瓷层厚度、表面粗糙度及硬度的影响,以及强化时间对成膜速度的影响。结果表明:陶瓷层厚度、表面粗糙度都随电流密度及强化时间的增大而增大,膜厚随二者增加有一极限值:硬度随电流密度增加而增加,也有一极限值:成膜速度在较低电流密度时不随时间而变,在较高电流密度时,成膜速度随时间增加而下降,最终趋于零,电流密度越高,下降速度越快。

  14. DEVELOPMENT OF CASTING TECHNOLOGIES DURING FORMATION OF PROPERTIES OF ALUMINUM-BASED MATERIALS WITH CARBON OF DIFFERENT STRUCTURAL CONDITION

    OpenAIRE

    A. T. Volochko

    2015-01-01

    The paper gives an assessment of existing casting methods used for manufacturing products from aluminum materials with carbon filling compounds. It presents results of comparative studies of properties of aluminum materials in which microcrystalline graphite, fullerene black, nanotubes and an amorphous phase of glass carbon have been used as filling compounds.

  15. DEVELOPMENT OF CASTING TECHNOLOGIES DURING FORMATION OF PROPERTIES OF ALUMINUM-BASED MATERIALS WITH CARBON OF DIFFERENT STRUCTURAL CONDITION

    Directory of Open Access Journals (Sweden)

    A. T. Volochko

    2015-11-01

    Full Text Available The paper gives an assessment of existing casting methods used for manufacturing products from aluminum materials with carbon filling compounds. It presents results of comparative studies of properties of aluminum materials in which microcrystalline graphite, fullerene black, nanotubes and an amorphous phase of glass carbon have been used as filling compounds.

  16. Thixoforming of 6066 aluminum alloy by multi-layer spray deposition

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Two thixoforming technologies of 6066 aluminum alloy (Al-1.37Si-1.37Mg-0.77Cu-0.07Mn) produced by multi-layer spray deposition process were studied. The spray-formed materials are of equiaxed and very fine grain (10~20  μm). And the grain size coarsens slower than that of conventional casting materials at temperature below the liquidus, which may relate to high temperature particles distributed along the grain boundaries. Extrusion and hot pressing were used as the thixoforming processes respectively. After extrusion the materials show a microstructure of mean grain size below 20  μm without obvious recrystallization. The mechanical properties achieved via extrusion and pressing in semi-solid state attain that of common wrought materials with shorter peak aging time of 4~5  h, about half of that in conventional condition.

  17. Preparation of semi-solid slurry containing fine and globular particles for wrought aluminum alloy 2024

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The semi-solid slurry of wrought aluminum alloy 2024 was prepared by a well developed rheocasting process, low superheat pouring with shearing field(LSPSF). The appreciate combination of pouring temperature and rotation speed of barrel, can give rise to a transition of the growth morphology of primary α(Al) from coarse-dendritic to coarse-particle-like and further to fine-globular. The combined effects of both localized rapid cooling and vigorous mixing during the initial stage of solidification can enhance wall nucleation and nuclei survival, which leads to the formation of fine-globular primary α(Al). By using semi-solid slurry prepared by LSPSF, direct squeeze cast cup-shaped component with improved mechanical properties such as yield strength of 198MPa, ultimate tensile strength of 306 MPa and elongation of 10.4%, can be obtained.

  18. Numerical simulation of temperature field in horizontal core-filling continuous casting for copper cladding aluminum rods

    Science.gov (United States)

    Su, Ya-jun; Liu, Xin-hua; Wu, Yong-fu; Huang, Hai-you; Xie, Jian-xin

    2013-07-01

    The steady-state temperature field of horizontal core-filling continuous casting (HCFC) for producing copper cladding aluminum rods was simulated by finite element method to investigate the effects of key processing parameters on the positions of solid-liquid interfaces (SLIs) of copper and aluminum. It is found that mandrel tube length and mean withdrawing speed have significant effects on the SLI positions of both copper and aluminum. Aluminum casting temperature ( T Al) (1003-1123 K) and secondary cooling water flux (600-900 L·h-1) have little effect on the SLI of copper but cause the SLI of aluminum to move 2-4 mm. When T Al is in a range of 1043-1123 K, the liquid aluminum can fill continuously into the pre-solidified copper tube. Based on the numerical simulation, reasonable processing parameters were determined.

  19. Surface treatment of new type aluminum lithium alloy and fatigue crack behaviors of this alloy plate bonded with Ti–6Al–4V alloy strap

    International Nuclear Information System (INIS)

    Highlights: ► A new generation aluminum lithium alloy which special made for Chinese commercial plane was investigated. ► Pattern of aluminum lithium alloy and Ti alloy were shown after anodization. ► Crack propagation of samples bonded with different wide Ti straps were studied in this paper. -- Abstract: Samples consisting of new aluminum lithium alloy (Al–Li alloy) plate developed by the Aluminum Company of America and Ti–6Al–4V alloy (Ti alloy) plate were investigated. Plate of 400 mm × 140 mm × 2 mm with single edge notch was anodized in phosphoric solution and Ti alloy plate of 200 mm × 20 (40) mm × 2 mm was anodized in alkali solution. Patterns of two alloys were studied at original/anodized condition. And then, aluminum alloy and Ti alloy plates were assembled into a sample with FM 94 film adhesive. Fatigue crack behaviors of the sample were investigated under condition of nominal stress σ = 36 MPa and 54 MPa, stress ratio of 0.1. Testing results show that anodization treatment modifies alloys surface topography. Ti alloy bonding to Al–Li alloy plate effectively retards crack growth than that of Al–Li alloy plate. Fatigue life of sample bonded with Ti alloy strap improves about 62.5% than that of non-strap plate.

  20. Microstructural characterization of as-cast hf-b alloys

    Directory of Open Access Journals (Sweden)

    João Carlos Jânio Gigolotti

    2012-04-01

    Full Text Available An accurate knowledge of several metal-boron phase diagrams is important to evaluation of higher order systems such as metal-silicon-boron ternaries. The refinement and reassessment of phase diagram data is a continuous work, thus the reevaluation of metal-boron systems provides the possibility to confirm previous data from an investigation using higher purity materials and better analytical techniques. This work presents results of rigorous microstructural characterization of as-cast hafnium-boron alloys which are significant to assess the liquid composition associated to most of the invariant reactions of this system. Alloys were prepared by arc melting high purity hafnium (minimum 99.8% and boron (minimum 99.5% slices under argon atmosphere in water-cooled copper crucible with non consumable tungsten electrode and titanium getter. The phases were identified by scanning electron microscopy, using back-scattered electron image mode and X-ray diffraction. In general, a good agreement was found between our data and those from the currently accepted Hafnium-Boron phase diagram. The phases identified are αHfSS and B-RhomSS, the intermediate compounds HfB and HfB2 and the liquide L. The reactions are the eutectic L ⇔ αHfSS + HfB and L ⇔ HfB2 + B-Rhom, the peritectic L + HfB2 ⇔ HfB and the congruent formation of HfB2.

  1. Microstructural characterization of as-cast Cr-Si alloys

    International Nuclear Information System (INIS)

    This work presents results of microstructural characterization of as-cast Cr-Si alloys. The alloys were prepared by arc melting pure Cr (min. 99.996%) and Si (min. 99.998%) powder mixtures under argon atmosphere in a water-cooled copper crucible with nonconsumable tungsten electrode and titanium getter. The phases were identified by scanning electron microscopy (SEM), using the back-scattered electron (BSE) image mode and X-ray diffraction (XRD). The results confirm the currently accepted Cr-Si phase diagram in terms of the invariant reactions and solid phases present in this system. Small corrections are proposed for the compositions of the liquid phase in the following reactions: (i) L ↔ CrSS+Cr3Si, from 15 to 16 at.% Si; (ii) L+αCr5Si3 ↔ CrSi, from 51 at.% Si to slightly above 53 at.% Si; (iii) L ↔ CrSi+CrSi2, from 56 to slightly above 57 at.% Si; (iv) L ↔ CrSi2+Si, from 82 to slightly above 85 at.% Si

  2. Mechanical properties of multicomponent cast high-strength martensitic titanium alloys

    International Nuclear Information System (INIS)

    The investigation of mechanical properties and workability of titanium alloys of the Ta-Al-Mo-V-Sn-Zn-Cu-Fe system with the purpose of alloy development for mold castings with σsub(u) >= 1100 MPa and high resistance to repeated static loads is performed. As optimum alloy for manufacturing power packs and details the alloy of the following composition is chosen: 5.5%Al, 3% Mo; 1.5% V; 1.0% Cu; 0.8% Fe; 1.5% Sn; 3.5% Zr (VT26L) having high stringth σsub(U)=1100... 1250 MPa, satisfactory plasticity ( delta=4...8%, PHI=8... 12%) resistance to repeated-static loads at the VT22 alloy level and satisfactory casting properties. It is established that the VT26L alloy has high level of properties upon casting, without any heat treatment

  3. Nanoreinforced Cast Al-Si Alloys with Al2O3, TiO2 and ZrO2 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Iman S. El-Mahallawi

    2015-05-01

    Full Text Available This study presents a new concept of refining and enhancing the properties of cast aluminum alloys by adding nanoparticles. In this work, the effect of adding alumina (Al2O3, titanium dioxide (TiO2 and zirconia (ZrO2 nano-particles (40 nm to the aluminum cast alloy A356 as a base metal matrix was investigated. Alumina, titanium dioxide and zirconia nano-powders were stirred in the A356 matrix with different fraction ratios ranging from (0%–5% by weight at variable stirring speeds ranging from (270, 800, 1500, 2150 rpm in both the semisolid (600 °C and liquid (700 °C state using a constant stirring time of one minute. The cast microstructure exhibited change of grains from dendritic to spherical shape with increasing stirring speed. The fracture surface showed the presence of nanoparticles at the interdendritic spacing of the fracture surface and was confirmed with EDX analysis of these particles. The results of the study showed that the mechanical properties (strength, elongation and hardness for the nanoreinforced castings using Al2O3, TiO2 and ZrO2 were enhanced for the castings made in the semi-solid state (600 °C with 2 weight% Al2O3 and 3 weight% TiO2 or ZrO2 at 1500 rpm stirring speed.

  4. Development of high plasticity Al-Si alloy and its casting process

    Institute of Scientific and Technical Information of China (English)

    郭国文; 李元元; 陈维平; 张大童; 龙雁

    2002-01-01

    Aiming to meet the challenge of the shape complexity and high plasticity demanded for the upper connective plate(UCP) in motorcycle, a high plasticity Al-Si alloy named HGZL-02 was developed by optimizing the chemical composition and casting process. Premium UCP castings were obtained by using optimized casting process. Results show that fine and dense microstructure are obtained in the UCP castings. An average of 224MPa in ultimate tensile strength, 149MPa in yield strength and 13.2% in elongation are achieved for T6 heat-treated UPS castings.

  5. The effect of microstructure of low-alloy spheroidal cast iron on impact strength

    Directory of Open Access Journals (Sweden)

    T. Szykowny

    2010-01-01

    Full Text Available The study presents an evaluation of the effect of microstructure of low-alloy spheroidal cast iron on impact strength within the temperature range from –60 to 100°C. Analyses were conducted on one type of cast iron containing 0.51% Cu and 0.72% Ni. Cast iron was austempered or normalized. Values of KCV and static mechanical properties were determined. Structural and fractographic analyses were based on light and scanning microscopy as well as X-ray diffraction. It was found that thermal processing considerably improves impact strength in relation to cast iron after casting. At the same time static mechanical properties are enhanced.

  6. The Effect of Impurities on the Processing of Aluminum Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zi-Kui Liu; Shengjun Zhang; Qingyou Han; Vinod Sikka

    2007-04-23

    For this Aluminum Industry of the Future (IOF) project, the effect of impurities on the processing of aluminum alloys was systematically investigated. The work was carried out as a collaborative effort between the Pennsylvania State University and Oak Ridge National Laboratory. Industrial support was provided by ALCOA and ThermoCalc, Inc. The achievements described below were made. A method that combines first-principles calculation and calculation of phase diagrams (CALPHAD) was used to develop the multicomponent database Al-Ca-K-Li-Mg-Na. This method was extensively used in this project for the development of a thermodynamic database. The first-principles approach provided some thermodynamic property data that are not available in the open literature. These calculated results were used in the thermodynamic modeling as experimental data. Some of the thermodynamic property data are difficult, if not impossible, to measure. The method developed and used in this project allows the estimation of these data for thermodynamic database development. The multicomponent database Al-Ca-K-Li-Mg-Na was developed. Elements such as Ca, Li, Na, and K are impurities that strongly affect the formability and corrosion behavior of aluminum alloys. However, these impurity elements are not included in the commercial aluminum alloy database. The process of thermodynamic modeling began from Al-Na, Ca-Li, Li-Na, K-Na, and Li-K sub-binary systems. Then ternary and higher systems were extrapolated because of the lack of experimental information. Databases for five binary alloy systems and two ternary systems were developed. Along with other existing binary and ternary databases, the full database of the multicomponent Al-Ca-K-Li-Mg-Na system was completed in this project. The methodology in integrating with commercial or other aluminum alloy databases can be developed. The mechanism of sodium-induced high-temperature embrittlement (HTE) of Al-Mg is now understood. Using the thermodynamic

  7. Current research progress in grain refinement of cast magnesium alloys: A review article

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Yahia; Qiu, Dong [School of Mechanical and Mining Engineering, University of Queensland, St Lucia, QLD 4072 (Australia); Jiang, Bin; Pan, Fusheng [College of Materials Science and Engineering, Chongqing University, Chongqing 400030 (China); Zhang, Ming-Xing, E-mail: Mingxing.Zhang@uq.edu.au [School of Mechanical and Mining Engineering, University of Queensland, St Lucia, QLD 4072 (Australia)

    2015-01-15

    Grain refinement of cast magnesium alloys, particularly in magnesium–aluminium (Mg–Al) based alloys, has been an active research topic in the past two decades, because it has been considered as one of the most effective approaches to simultaneously increase the strength, ductility and formability. The development of new grain refiners was normally based on the theories/models that were established through comprehensive and considerable studies of grain refinement in cast Al alloys. Generally, grain refinement in cast Al can be achieved through either inoculation treatment, which is a process of adding, or in situ forming, foreign particles to promote heterogeneous nucleation rate, or restricting grain growth by controlling the constitutional supercooling or both. But, the concrete and tangible grain refinement mechanism in cast metals is still not fully understood and there are a number of controversies. Therefore, most of the new developed grain refiners for Mg–Al based alloys are not as efficient as the commercially available ones, such as zirconium in non-Al containing Mg alloys. To facilitate the research in grain refinement of cast magnesium alloys, this review starts with highlighting the theoretical aspects of grain refinement in cast metals, followed by reviewing the latest research progress in grain refinement of magnesium alloys in terms of the solute effect and potent nucleants.

  8. Current research progress in grain refinement of cast magnesium alloys: A review article

    International Nuclear Information System (INIS)

    Grain refinement of cast magnesium alloys, particularly in magnesium–aluminium (Mg–Al) based alloys, has been an active research topic in the past two decades, because it has been considered as one of the most effective approaches to simultaneously increase the strength, ductility and formability. The development of new grain refiners was normally based on the theories/models that were established through comprehensive and considerable studies of grain refinement in cast Al alloys. Generally, grain refinement in cast Al can be achieved through either inoculation treatment, which is a process of adding, or in situ forming, foreign particles to promote heterogeneous nucleation rate, or restricting grain growth by controlling the constitutional supercooling or both. But, the concrete and tangible grain refinement mechanism in cast metals is still not fully understood and there are a number of controversies. Therefore, most of the new developed grain refiners for Mg–Al based alloys are not as efficient as the commercially available ones, such as zirconium in non-Al containing Mg alloys. To facilitate the research in grain refinement of cast magnesium alloys, this review starts with highlighting the theoretical aspects of grain refinement in cast metals, followed by reviewing the latest research progress in grain refinement of magnesium alloys in terms of the solute effect and potent nucleants

  9. Electrochemical behavior of Co-Cr and Ni-Cr dental cast alloys

    Institute of Scientific and Technical Information of China (English)

    Viswanathan S. SAJI; Han-Cheol CHOE

    2009-01-01

    The cast structures influencing the electrochemical corrosion behavior of Co-Cr and Ni-Cr dental alloys were studied using potentiodynamic polarization and AC impedance in 0.9% (mass fraction) NaCl solution at (37±1) ℃. The phase and microstructure of the alloys that were fabricated using two different casting methods viz. centrifugal casting and high frequency induction casting, were examined using X-ray diffraction analysis, scanning electron microscopy and energy dispersive spectroscopy. The roles of alloying elements and the passive film homogeneity on the corrosion resistance of Co-Cr-Mo and Ni-Cr-Mo dental cast alloys were reviewed. The results of electrochemical study show that the dependence of corrosion resistance on the microstructure associated with the casting methods is marginal. The Co-Cr alloy exhibits more desirable corrosion resistance properties than the Ni-Cr alloy. There is severe preferential dissolution of Ni-rich, Cr and Mo depleted zones in the Ni-Cr alloy.

  10. Bearing Strengths of Some Wrought-aluminum Alloys

    Science.gov (United States)

    Moore, R L; Wescoat, C

    1943-01-01

    Although a number of investigations of the bearing strength of aluminum alloys have been made, the problem remains one of considerable interest to the aircraft industry. For this reason it has seemed advisable to make additional tests of the commonly used aircraft alloys in an effort to establish a better basis for the selection of allowable bearing values. Current design practice does not recognize the effect of edge distance upon bearing strengths, and for this reason edge distance was one of the principal variables considered in this investigation. The increasing emphasis being placed upon permanent set limitations makes it essential that more information on bearing yield phenomena be obtained. The object of this investigation was to determine bearing yield and ultimate strengths of the following aluminum alloy products: 17S-T, 24S-T, Alclad 24S-T, 24S-RT, 52S-0, 52S-1/2H, 52S-H, 53S-T, and 61S-T extrusions. Ratios of these bearing properties to tensile properties were also determined.

  11. Research of Mechanical Property Gradient Distribution of Al-Cu Alloy in Centrifugal Casting

    Science.gov (United States)

    Sun, Zhi; Sui, Yanwei; Liu, Aihui; Li, Bangsheng; Guo, Jingjie

    Al-Cu alloy castings are obtained using centrifugal casting. The regularity of mechanical property gradient distribution of Al-Cu alloy castings with the same centrifugal radius at different positions is investigated. The result shows that the tensile strength, yield strength, elongation and microscope hardness exhibit the following gradient distribution characteristic — high on both sides and low on the center. The trend of mechanical property gradient distribution of Al-Cu alloy increases with the increase in the rotation speed. Moreover, the mechanical properties of casting centerline two sides have asymmetry. The reason is that the grain size of casting centerline two sides and Al2Cu phase and Cu content change correspondingly.

  12. Evaluation of the importance of rheological model accuracy on the numerical simulation of the pressure die-casting of thixotropic light alloys

    International Nuclear Information System (INIS)

    The use of thixotropic or semi-solid light alloys (magnesium and aluminum alloys) in the manufacture of various components, particularly in the automotive field, offers many advantages. While such alloys are used in a number of different manufacturing processes, the concern here is with the die-casting of components using these alloys. The improvement of this process and the application of the process in the production of a wider range of cast components can be considerably aided by the use of accurate numerical simulations of the entire process provided that these simulations have been shown to be accurate particularly in their prediction of the development of faults in the castings. One the major difficulties encountered in the simulation of the pressure die-casting of thixotropic alloys is the identification of an accurate model to describe the rheological properties of the alloys involved and to be able to judge how accurately the parameters in such a model have to be known in order to adequately predict the casting and, in particular, to predict the formation of faults in the cast components. The present study is based on the use of the ProCAST software with its thixo-module platform. A series of generic components were selected and the casting of these components using different rheological models was numerically studied, particular attention being paid to the formation of faults in the components during the casting process. Three rheological models were examined in detail in the present study - a Newtonian model, a Power Law Cut-off non-Newtonian model and a Carreau-Yasuda non-Newtonian model being considered. The effect of the model used on the prediction of the mold filling and on the properties of the cast component have been considered for the various generic components. In addition, the effect of changes in the values of the model parameters on the casting predictions has been studied and it has also been shown that highly accurate values for all of the

  13. Development of a discriminatory biocompatibility testing model for non-precious dental casting alloys.

    LENUS (Irish Health Repository)

    McGinley, Emma Louise

    2011-12-01

    To develop an enhanced, reproducible and discriminatory biocompatibility testing model for non-precious dental casting alloys, prepared to a clinically relevant surface finishing condition, using TR146 oral keratinocyte cells.

  14. GAS-CREATION OF SEPARATING COVERINGS FOR MOULDS FOR DIE CASTING OF ALUMINIUM ALLOYS

    OpenAIRE

    A. M. Mihaltsov; A. A. Pivovarchik; A. A. Subota

    2016-01-01

    The methods of experiments on determination of gascreating ability of different separating coverings for the moulds of aluminium alloys die casting are given and described in the article, and the results of investigation are given as well.

  15. Characteristics of Fe-28Mn-6Si-5Cr shape memory alloy produced by centrifugal casting

    International Nuclear Information System (INIS)

    Recent application of ferrous shape memory alloys, particularly Fe-Mn-Si alloys as pipe joints used for a tunnel driving technique in the field of civil engineering, requires efficient production of alloy pipes. Centrifugal casting is one of the efficient manufacturing techniques which can produce suitable sizes of pipes of approximately 4 to 14 inches in outside diameter. The mechanical properties of the centrifugally cast Fe-Mn-Si shape memory alloy were investigated to have 700 MPa in tensile strength and shape recovery of ∝3% of the initial deformation. The shape recovery achieved by the centrifugally cast materials proved to be comparable to that of the rolled materials. The TEM microstructure of the centrifugally cast materials deformed necessarily in the process of shape recovery reveals random distribution of ε (hcp) bands containing many dislocations inside, whereas the structure of the rolled materials shows ε phases containing fewer dislocations. (orig.)

  16. Strengthening Aluminum Alloys for High Temperature Applications Using Nanoparticles of Al203 and Al3-X Compounds (X= Ti, V, Zr)

    Science.gov (United States)

    Lee, Jonathan A.

    2007-01-01

    In this paper the effect of nanoparticles A12O3 and A13-X compounds (X= Ti, V, Zr) on the improvement of mechanical properties of aluminum alloys for elevated temperature applications is presented. These nanoparticles were selected based on their chemical stability and low diffusions rates in aluminum matrix at high temperatures. The strengthening mechanism for aluminum alloy is based on the mechanical blocking of dislocation movements by these nanoparticles. Samples were prepared from A12O3 nanoparticle preforms, which were produced using ceramic injection molding process and pressure infiltrated by molten aluminum. A12O3 nanoparticles can also be homogeneously mixed with aluminum powder and consolidated into samples through hot pressing and sintering. On the other hand, the Al3-X nanoparticles are produced as precipitates via in situ reactions with molten aluminum alloys using conventional casting techniques. The degree of alloy strengthening using nanoparticles will depend on the materials, particle size, shape, volume fraction, and mean inter-particle spacing.

  17. Effect of pressure on heat transfer coefficient at the metal/mold interface of A356 aluminum alloy

    DEFF Research Database (Denmark)

    Fardi Ilkhchy, A.; Jabbari, Masoud; Davami, P.

    2012-01-01

    The aim of this paper is to correlate interfacial heat transfer coefficient (IHTC) to applied external pressure, in which IHTC at the interface between A356 aluminum alloy and metallic mold during the solidification of casting under different pressures were obtained using the inverse heat...... presented for correlation between external pressure and heat transfer coefficient. Acceptable agreement with data in literature shows the accuracy of the proposed formula....... conduction problem (IHCP) method. The method covers the expedient of comparing theoretical and experimental thermal histories. Temperature profiles obtained from thermocouples were used in a finite difference heat flow program to estimate the transient heat transfer coefficients. The new simple formula was...

  18. Thin Wall Ductile Iron Castings: Technological Aspects

    Directory of Open Access Journals (Sweden)

    E Fraś

    2013-01-01

    Full Text Available The paper discusses the reasons for the current trend of substituting ductile iron castings by aluminum alloys castings.However, it has been shown that ductile iron is superior to aluminum alloys in many applications. In particular it has beendemonstrated that is possible to produce thin wall wheel rim made of ductile iron without the development of chills, coldlaps or misruns. In addition it has been shown that thin wall wheel rim made of ductile iron can have the same weight, andbetter mechanical properties, than their substitutes made of aluminum alloys.

  19. Evolution of Fe Bearing Intermetallics During DC Casting and Homogenization of an Al-Mg-Si Al Alloy

    Science.gov (United States)

    Kumar, S.; Grant, P. S.; O'Reilly, K. A. Q.

    2016-04-01

    The evolution of iron (Fe) bearing intermetallics (Fe-IMCs) during direct chill casting and homogenization of a grain-refined 6063 aluminum-magnesium-silicon (Al-Mg-Si) alloy has been studied. The as-cast and homogenized microstructure contained Fe-IMCs at the grain boundaries and within Al grains. The primary α-Al grain size, α-Al dendritic arm spacing, IMC particle size, and IMC three-dimensional (3D) inter-connectivity increased from the edge to the center of the as-cast billet; both α c-AlFeSi and β-AlFeSi Fe-IMCs were identified, and overall α c-AlFeSi was predominant. For the first time in industrial billets, the different Fe-rich IMCs have been characterized into types based on their 3D chemistry and morphology. Additionally, the role of β-AlFeSi in nucleating Mg2Si particles has been identified. After homogenization, α c-AlFeSi predominated across the entire billet cross section, with marked changes in the 3D morphology and strong reductions in inter-connectivity, both supporting a recovery in alloy ductility.

  20. Evolution of Fe Bearing Intermetallics During DC Casting and Homogenization of an Al-Mg-Si Al Alloy

    Science.gov (United States)

    Kumar, S.; Grant, P. S.; O'Reilly, K. A. Q.

    2016-06-01

    The evolution of iron (Fe) bearing intermetallics (Fe-IMCs) during direct chill casting and homogenization of a grain-refined 6063 aluminum-magnesium-silicon (Al-Mg-Si) alloy has been studied. The as-cast and homogenized microstructure contained Fe-IMCs at the grain boundaries and within Al grains. The primary α-Al grain size, α-Al dendritic arm spacing, IMC particle size, and IMC three-dimensional (3D) inter-connectivity increased from the edge to the center of the as-cast billet; both α c-AlFeSi and β-AlFeSi Fe-IMCs were identified, and overall α c-AlFeSi was predominant. For the first time in industrial billets, the different Fe-rich IMCs have been characterized into types based on their 3D chemistry and morphology. Additionally, the role of β-AlFeSi in nucleating Mg2Si particles has been identified. After homogenization, α c-AlFeSi predominated across the entire billet cross section, with marked changes in the 3D morphology and strong reductions in inter-connectivity, both supporting a recovery in alloy ductility.

  1. Influence of casting defects on fatigue strength of an investment cast Ti-6Al-4V alloy

    Directory of Open Access Journals (Sweden)

    Léopold Gaëlle

    2014-06-01

    Full Text Available The influence of casting defects on fatigue strength of an investment cast Ti-6Al-4V alloy is investigated. The most common of these defects are: pinhole, linear defect and inclusion. Each of them is currently defined by its size, morphology and position from the surface but is different from each other for a same type. An experimental campaign is defined with different types of defect. The first part of the campaign is focused on the influence of an artificial and spherical defect, considering two different surface conditions. It is shown that fatigue behaviour of this alloy is very sensitive to the surface condition of this artificial defect despite stress concentrations at the tip of the defect. The second part of the campaign is focused on casting defects: reduction of fatigue life is quantified and it is shown that an electro-discharge machined defect cannot be representative of pinhole.

  2. Development of a Two-Phase Model for the Hot Deformation of Highly-Alloyed Aluminum

    Energy Technology Data Exchange (ETDEWEB)

    A. J. Beaudoin; J. A. Dantzig; I. M. Robertson; B. E. Gore; S. F. Harnish; H. A. Padilla

    2005-10-31

    Conventional processing methods for highly alloyed aluminum consist of ingot casting, followed by hot rolling and thermal treatments. Defects result in lost productivity and wasted energy through the need to remelt and reprocess the material. This research centers on developing a fundamental understanding for deformation of wrought 705X series alloys, a key alloy system used in structural airframe applications. The development of damage at grain boundaries is characterized through a novel test that provides initiation of failure while preserving a controlled deformation response. Data from these mechanical tests are linked to computer simulations of the hot rolling process through a critical measure of damage. Transmission electron microscopy provides fundamental insight into deformation at these high working temperatures, and--in a novel link between microscale and macroscale response--the evolution of microstructure (crystallographic orientation) provides feedback for tuning of friction in the hot rolling process. The key product of this research is a modeling framework for the analysis of industrial hot rolling.

  3. Effect of inter-critical quenching on mechanical properties of casting low-alloy steel

    OpenAIRE

    Liu Zhongli; Shang Yong

    2013-01-01

    For some casting low-alloy steels, traditional quenching and tempering heat treatments can improve the strength; however, sometimes the ductility is not satisfied. Therefore, some kind of effective heat treatment method seems necessary; one which could improve the ductility, but not seriously affect the strength. In this paper, the effect of inter-critical quenching (IQ) on the mechanical properties of casting low-alloy steel was studied. IQ was added between quenching and tempering heat trea...

  4. Derivative thermo analysis of the Al-Si cast alloy with addition of rare earths metals

    Directory of Open Access Journals (Sweden)

    M. Krupiński

    2010-01-01

    Full Text Available In this paper the dependence between chemical composition, structure and cooling rate of Al–Si aluminium cast alloy was investigated. For studying of the structure changes the thermo-analysis was carried out, using the UMSA (Universal Metallurgical Simulator and Analyzer device. For structure investigation optical and electron scanning microscopy was used, phase and chemical composition of the Al cast alloy also using qualitative point-wise EDS microanalysis.

  5. Derivative thermo analysis of the Al-Si cast alloy with addition of rare earths metals

    OpenAIRE

    M. Krupiński; K. Labisz; L.A. Dobrzański; Z. Rdzawski

    2010-01-01

    In this paper the dependence between chemical composition, structure and cooling rate of Al–Si aluminium cast alloy was investigated. For studying of the structure changes the thermo-analysis was carried out, using the UMSA (Universal Metallurgical Simulator and Analyzer) device. For structure investigation optical and electron scanning microscopy was used, phase and chemical composition of the Al cast alloy also using qualitative point-wise EDS microanalysis.

  6. Upgrading the alloy AlSi6Cu4 (AK64) cast to the ceramic mould

    OpenAIRE

    M. Dudyk; J. Asłanowicz; L. Ościłowski

    2007-01-01

    In this article are presented the results of study on the kinetics of the crystallization processes in the refined, modified and filtered Silumin containing copper and the metallographic analysis of the obtained structures. Impact of the upgrading processes – refining, modification and filtration – of the studied alloy AK64 on changes of the impact strength KCV of the cast samples. Original metallographic analysis of the foam filters cast with the studied alloy was carried out. The efficiency...

  7. Effect of Squeeze Cast Process Parameters on Fluidity of Hypereutectic Al-Si Alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effects of processing variables on the fluidity of hypereutectic Al-Si alloy melt during squeeze casting were investigated. The maximum fluidity of Al-16.0%Si alloy during squeeze casting was obtained under the applied pressure of 30 MPa. The fluidity increased with superheat. The fluidity increased with silicon content in the range from 12.0% to 20.0%. That was decreased respectively by eutectic modification and primary silicon refinement.

  8. Energy Saving Melting and Revert Reduction Technology (Energy-SMARRT): Light Metals Permanent Mold Casting

    Energy Technology Data Exchange (ETDEWEB)

    Fasoyinu, Yemi [CanmetMATERIALS

    2014-03-31

    Current vehicles use mostly ferrous components for structural applications. It is possible to reduce the weight of the vehicle by substituting these parts with those made from light metals such as aluminum and magnesium. Many alloys and manufacturing processes can be used to produce these light metal components and casting is known to be most economical. One of the high integrity casting processes is permanent mold casting which is the focus of this research report. Many aluminum alloy castings used in automotive applications are produced by the sand casting process. Also, aluminum-silicon (Al-Si) alloys are the most widely used alloy systems for automotive applications. It is possible that by using high strength aluminum alloys based on an aluminum-copper (Al-Cu) system and permanent mold casting, the performance of these components can be enhanced significantly. This will also help to further reduce the weight. However, many technological obstacles need to be overcome before using these alloys in automotive applications in an economical way. There is very limited information in the open literature on gravity and low-pressure permanent mold casting of high strength aluminum alloys. This report summarizes the results and issues encountered during the casting trials of high strength aluminum alloy 206.0 (Al-Cu alloy) and moderate strength alloy 535.0 (Al-Mg alloy). Five engineering components were cast by gravity tilt-pour or low pressure permanent mold casting processes at CanmetMATERIALS (CMAT) and two production foundries. The results of the casting trials show that high integrity engineering components can be produced successfully from both alloys if specific processing parameters are used. It was shown that a combination of melt processing and mold temperature is necessary for the elimination of hot tears in both alloys.

  9. Effect of tempering temperature on the properties of low-alloy cast steel

    Directory of Open Access Journals (Sweden)

    D. Bartocha

    2011-07-01

    Full Text Available The mechanical properties of cast steel are primarily a function of chemical composition and solidification conditions i.e. primary structure, however, them can be change in a limited extent, by heat treatment. In the article the influence parameters of quenching on mechanical properties of low-alloy structural cast steel, modeled in terms of chemical composition, on the cast steel L20HGSNM, are presented. An attempt to quantify this relationship was made.

  10. The technology of precision casting of titanium alloys by centrifugal process

    OpenAIRE

    A. Karwiński; W. Leśniewski; S. Pysz; P. Wieliczko

    2011-01-01

    The article describes the development of a procedure for the preparation of foundry ceramic moulds and making first test castings. The presented studies included:development of technological parameters of the ceramic mould preparation process using water-based zirconium binders and zirconia ceramic materials, where moulds are next used for the centrifugal casting of titanium alloys melted in vacuum furnaces, designing of pouring process using simulation software, making test castings,testing ...

  11. Effect of Coolant Water Flow Rate on Aluminum Alloys Corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Golosov, O.A. [Institute of Nuclear Materials, Zarechny, Sverdlovsk region, 624250 (Russian Federation)

    2011-07-01

    One of the most important factors limiting a life-time of fuel elements in high-flux research reactors are a corrosion rate of fuel cladding material and a formation rate of oxide film. This study presents the results of the corrosion tests with and without irradiation. The aluminum alloys systems Al-Fe-Ni, Al-Fe-Ni-Cu-Mg and Al-Mg-Si-Cu were irradiated in the water flow of a velocity from 1.3 to 14.2m/s at 200 {sup o}C for time within 570 to 2000 hours. (author)

  12. Corrosion fatigue of 2219-T87 aluminum alloy

    Science.gov (United States)

    Mcmillan, V. C.

    1986-01-01

    Corrosion fatigue studies were conducted on bare, chemical conversion coated, and anodized 2219-T87 aluminum alloy. These tests were performed using a rotating beam machine running at a velocity of 2500 rpm. The corrosive environments tested were distilled water, 100 ppm NaCl, and 3.5 percent NaCl. Results were compared to the endurance limit in air. An evaluation of the effect of protective coatings on corrosion fatigue was made by comparing the fatigue properties of specimens with coatings to those without.

  13. Corrosion damage evolution and residual strength of corroded aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    Youhong Zhang; Guozhi Lv; Hui Wang; Bomei Si; Yueliang Cheng

    2008-01-01

    The LY12CZ aluminum alloy specimens were eurroded under the conditions of different test temperatures and exposure durations. After corrosion exposure, fatigue tests were performed. Scanning electron microscopy and optical microscope analyses on corrosion damage were carried out. The definition of surface corrosion damage ratio was provided to describe the extent of surface corrosion damage. On the basis of the measured data sets of the corrosion damage ratio, the probabilistic model of corrosion damage evolution was built. The corrosion damage decreased the fatigue life by a factor of about 1.25 to 2.38 and the prediction method of residual strength of the corroded structure was presented.

  14. Sensors Array Technique for Monitoring Aluminum Alloy Spot Welding

    Institute of Scientific and Technical Information of China (English)

    王蕤; 罗震; 单平; 步贤政; 袁书现; 敖三三

    2010-01-01

    In this paper,the sensors array technique is applied to the quality detection of aluminum alloy spot welding.The sensors array has three forms,i.e.,linear magnetic sensors array,annular magnetic sensors array and cross magnetic sensors array.An algorithm based on principal component analysis is proposed to extract the signal eigenvalues.The three types of magnetic sensors array are used in the experiment of monitoring the signal.After the eigenvalues are extracted,they are used to build a relationship with ...

  15. Interdiffusion in binary cast and powders W-Re and Mo-Re alloys

    International Nuclear Information System (INIS)

    Concentration dependences of diffusion coefficients in the cast and powder alloys of the W-Re and Mo-Re systems are obtained. It is shown, that in spite of the fact that the diffusion coefficients values in dispersed materials are higher than in the cast ones, the peculiarities of the concentration dependences are common for both cases

  16. Annealing of chromium oxycarbide coatings deposited by plasma immersion ion processing (PIIP) for aluminum die casting

    International Nuclear Information System (INIS)

    Chromium oxycarbide coatings have been investigated for use as non-wetting coatings for aluminum die casting. This paper examines Cr-C-O coating stability and non-wetability at elevated temperatures for extended periods. Coatings were deposited onto 304 stainless steel from chromium carbonyl [Cr(CO)6] by plasma immersion ion processing. The coatings were annealed in air at an aluminum die casting temperature of 700 deg. C up to 8 h. Coatings were analyzed using resonant ion backscattering spectroscopy, nanoindentation and pin-on-disk tribometry. Molten aluminum was used to determine coating wetting and contact angle. Results indicate that the surface oxide layer reaches a maximum thickness of 900 nm. Oxygen concentrations in the coatings increased from 24% to 34%, while the surface concentration rose to almost 45%. Hardness values ranged from 22.1 to 6.7 GPa, wear coefficients ranged from 21 to 8x10-6 mm3/Nm and contact angles ranged from 156 deg. to 127 deg

  17. Annealing of chromium oxycarbide coatings deposited by plasma immersion ion processing (PIIP) for aluminum die casting

    Science.gov (United States)

    Peters, A. M.; He, X. M.; Trkula, M.; Nastasi, M.

    2001-04-01

    Chromium oxycarbide coatings have been investigated for use as non-wetting coatings for aluminum die casting. This paper examines Cr-C-O coating stability and non-wetability at elevated temperatures for extended periods. Coatings were deposited onto 304 stainless steel from chromium carbonyl [Cr(CO) 6] by plasma immersion ion processing. The coatings were annealed in air at an aluminum die casting temperature of 700°C up to 8 h. Coatings were analyzed using resonant ion backscattering spectroscopy, nanoindentation and pin-on-disk tribometry. Molten aluminum was used to determine coating wetting and contact angle. Results indicate that the surface oxide layer reaches a maximum thickness of 900 nm. Oxygen concentrations in the coatings increased from 24% to 34%, while the surface concentration rose to almost 45%. Hardness values ranged from 22.1 to 6.7 GPa, wear coefficients ranged from 21 to 8×10 -6 mm3/ Nm and contact angles ranged from 156° to 127°.

  18. Material and information flows pertaining to aluminum alloy pipe distribution

    Directory of Open Access Journals (Sweden)

    D. Simić

    2013-10-01

    Full Text Available This paper discusses the distribution flow of aluminum (Al alloy pipes, starting with the completion of the manufacturing process and final inspection. The proposed solution considers the use of bar-coded caps produced from recycled polymer materials that are placed on the ends of the tubes in order to achieve protection against potential changes in material properties and preserve the product quality. For the preparation of capped tube bundles for shipment from the manufacturer output storage to the customer input warehouse, a technical solution that enables correct and efficient Al alloy pipe handling is proposed, in terms of safety, security, reliability, financial feasibility and ecological viability, with optimal utilization of transport and storage.

  19. Corrosion and protection of heterogeneous cast Al-Si (356) and Al-Si-Cu-Fe (380) alloys by chromate adn cerium inhibitors

    Science.gov (United States)

    Jain, Syadwad

    In this study, the localized corrosion and conversion coating on cast alloys 356 (Al-7.0Si-0.3Mg) and 380 (Al-8.5Si-3.5Cu-1.6Fe) were characterized. The intermetallic phases presence in the permanent mold cast alloy 356 are primary-Si, Al5FeSi, Al8Si6Mg3Fe and Mg2Si. The die cast alloy 380 is rich in Cu and Fe elements. These alloying elements result in formation of the intermetallic phases Al 5FeSi, Al2Cu and Al(FeCuCr) along with primary-Si. The Cu- and Fe-rich IMPS are cathodic with respect to the matrix phase and strongly govern the corrosion behavior of the two cast alloys in an aggressive environment due to formation of local electrochemical cell in their vicinity. Results have shown that corrosion behavior of permanent mould cast alloy 356 is significantly better than the die cast aluminum alloy 380, primarily due to high content of Cu- and Fe-rich phases such as Al2Cu and Al 5FeSi in the latter. The IMPS also alter the protection mechanism of the cast alloys in the presence of inhibitors in an environment. The presence of chromate in the solution results in reduced cathodic activity on all the phases. Chromate provides some anodic inhibition by increasing pitting potentials and altering corrosion potentials for the phases. Results have shown that performance of CCC was much better on 356 than on 380, primarily due to inhomogeneous and incomplete coating deposition on Cu- and Fe- phases present in alloy 380. XPS and Raman were used to characterize coating deposition on intermetallics. Results show evidence of cyanide complex formation on the intermetallic phases. The presence of this complex is speculated to locally suppress CCC formation. Formation and breakdown of cerium conversion coatings on 356 and 380 was also analyzed. Results showed that deposition of cerium hydroxide started with heavy precipitation on intermetallic particles with the coatings growing outwards onto the matrix. Electrochemical analysis of synthesized intermetallics compounds in the

  20. A Rare Earth High-iron Aluminum Alloy Cable Company to Settle in Chongqing

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>On September 14,the reporter learnt from the Seminar on Application of New Rare Earth High-iron Aluminum Alloy Cable Technologies for Energy Conservation and Environmental Protection held by Chongqing Electric Industry Association that a rare earth high-iron aluminum alloy cable company with

  1. Corrosion Behavior of the As-cast and Heat-treated ZA27 Alloy

    Directory of Open Access Journals (Sweden)

    B. Bobic

    2011-06-01

    Full Text Available Corrosion behaviour of the as-cast and heat-treated ZA27 alloy was examined. The alloy was prepared by conventional melting and casting route and then thermally processed by applying T4 heat treatment regime (solutionizing at 370 °C for 3 hours followed by water quenching and natural aging. Corrosion rate of the as-cast and heat-treated ZA27 alloy was determined in 3.5 wt. % NaCl solution through immersion test using both weight loss method and polarization resistance measurements. It was shown that applied thermal treatment resulted in increased ductility of the heat-treated alloy and had a small beneficial effect on the corrosion resistance of ZA27 alloy.

  2. Contrasting LME in aluminum and nickel alloys, with overtones to SCC

    International Nuclear Information System (INIS)

    The susceptibility of Alloys 400, 600, 200 and 800 to liquid metal embrittlement (LME), hydrogen embrittlement and stress corrosion cracking are in that order (most to least). Correlations exist, too, in the cracking mode, intergranular or transgranular. Accordingly, understanding LME and LME tests have potential uses in alloy development and screening. The use of a quick indentation test for LME is described that worked admirably for aluminum alloys but did not work for nickel-base alloys. The problem is that LME is strain rate sensitive in nickel alloys but not in aluminum alloys. This is believed to be a wetting issue

  3. The use of surface modification techniques for the corrosion protection of aluminum and aluminum alloys

    International Nuclear Information System (INIS)

    Surface modification techniques such as ion beam assisted deposition (IBAD) and radio frequency plasma enhanced chemical vapor deposition (PECVD) offer a means to produce surfaces with unique and improved properties. This paper reviews the advantages of the IBAD and PECVD processes and discusses the preparation and pitting corrosion behavior of IBAD modified aluminum surfaces and PECVD coatings on a 7075 aluminum alloy. Pitting potential values for the base materials and for the base materials with silicon nitride IBAD, tantalum oxide IBAD, or PECVD diamond-like carbon coatings were determined in deaerated 0.1M NaCl solutions. The thickness of the modified region ranged from 0.01 to 5.0 microm. All three coatings improved the resistance to pit initiation

  4. Structure changes and mechanical properties of laser alloyed magnesium cast alloys

    OpenAIRE

    W. Kwaśny; T. Tański,; Sz. Malara; J. Domagała; L.A. Dobrzański

    2009-01-01

    Purpose: The aim of this work was to investigate structure and mechanical properties of the MCMgAl12Zn1 casting magnesium alloys after laser treatment. The laser treatment was carried out using a high power diode laser (HPDL).Design/methodology/approach: The laser processing of TiC, WC, SiC particles in MCMgAl12Zn1 and the resulted microstructures and properties are discussed in this paper. The resulting microstructure in the modified surface layer was examined. Phase composition was...

  5. Single-aging characteristics of 7055 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; YIN Zhi-min; SHEN Kai; LI Jie; HUANG ji-wu

    2007-01-01

    The microstructures and properties of 7055 aluminum alloy were studied at different single-aging for up to 48 h using hardness test, tensile test, electrical conductivity measurement, XRD and TEM microstructure analysis. The results show that at the early stage of aging, the hardness and strength of the alloy increase rapidly, the peak hardness and strength are approached after 120 ℃ aging for 4 h, then maintained at a high level for a long time. The suitable single-aging treatment of 7055 alloy is 480 ℃, 1 h solution treatment and water quenching, then aging at 120 ℃ for 24 h. Under those condition, the tensile strength, yield strength, elongation and electrical conductivity of the studied alloy are 513 MPa, 462 MPa, 9.5% and 29%(IACS), respectively. During aging, the solid solution decomposes and precipitation occurs. At the early aging stage of 120 ℃, GP zones form and then grow up gradually with increasing ageing time. η' phase forms after ageing for 4 h and η phase starts to occur after 24 h aging.

  6. Retention and release of tritium in aluminum clad, Al-Li alloys

    International Nuclear Information System (INIS)

    Tritium retention in and release from aluminum clad, aluminum-lithium alloys is modeled from experimental and operational data developed during the thirty plus years of tritium production at the Savannah River Site. The model assumes that tritium atoms, formed by the 6Li(n,α)3He reaction, are produced in solid solution in the Al-Li alloy. Because of the low solubility of hydrogen isotopes in aluminum alloys, the irradiated Al-Li rapidly becomes supersaturated in tritium. Newly produced tritium atoms are trapped by lithium atoms to form a lithium tritide. The effective tritium pressure required for trap or tritide stability is the equilibrium decomposition pressure of tritium over a lithium tritide-aluminum mixture. The temperature dependence of tritium release is determined by the permeability of the cladding to tritium and the local equilibrium at the trap sites. This model is used to calculate tritium release from aluminum clad, aluminum-lithium alloys. 9 refs., 3 figs

  7. Changes of Tempering Microstructure and Properties of Fe-Cr-V-Ni-Mn-C Cast Alloys

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-xia; MA Yong-qing; WANG Yue-hua; ZHANG Zhan-ping; ZHANG Yang

    2004-01-01

    The changes of tempering microstructure and properties of Fe-Cr-V-Ni-Mn-C cast alloys with martensite matrix and much retained austenite are studied. The results showed that when tempering at 200℃ the amount of retained austenite in the alloys is so much that is nearly to as-cast, and a lot of retained austenite decomposes when tempering at 350℃ and the retained austenite decomposes almost until tempering at 560℃. When tempering at 600℃, the retained austenite in the alloys all decomposes. At 560℃ the hardness is highest due to secondary hardening. The effect of nickel and manganese on the microstructure and properties of Fe-Cr-V-C cast alloy were also studied. The results show that the Fe-Cr-V-C cast alloy added nickel and manganese can obtain martensite matrix and much retained austenite microstructure, and nickel can also prevent pearlite transformation. With the increasing content of nickel and manganese, the hardness of as-cast alloy will decreases gradually, so one can improve the hardness of alloy by tempering process. When the content of nickel and manganese is 1.3~1.7%, the hardness of secondary hardening is the highest (HRC64). But when the content of nickel and manganese increase continually, the hardness of secondary hardening is low slightly, and the tempering temperature of secondary hardening rises.

  8. High-strength and high-RRR Al-Ni alloy for aluminum-stabilized superconductor

    CERN Document Server

    Wada, K; Sakamoto, H; Yamamoto, A; Makida, Y

    2000-01-01

    The precipitation type aluminum alloys have excellent performance as the increasing rate in electric resistivity with additives in the precipitation state is considerably low, compared to that of the aluminum alloy with additives in the solid-solution state. It is possible to enhance the mechanical strength without remarkable degradation in residual resistivity ratio (RRR) by increasing content of selected additive elements. Nickel is the suitable additive element because it has very low solubility in aluminum and low increasing rate in electric resistivity, and furthermore, nickel and aluminum form intermetallic compounds which effectively resist the motion of dislocations. First, Al-0.1wt%Ni alloy was developed for the ATLAS thin superconducting solenoid. This alloy achieved high yield strength of 79 MPa (R.T.) and 117 MPa (4.2 K) with high RRR of 490 after cold working of 21% in area reduction. These highly balanced properties could not be achieved with previously developed solid-solution aluminum alloys. ...

  9. Interfacial study of semi-solid aluminum alloy and stainless steel sheathed extrusion

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-wei; GUO Cheng; LIU Xu-feng; SHAO Guang-jie

    2006-01-01

    Using sheathed extrusion technique, the bonding and forming of semi solid aluminum alloy with stainless steel sheath are successfully realized. The relationship between the interfacial shear strength and the solid fraction of semi solid aluminum alloy at different extrusion ratios is analyzed; the interfacial and fracture structure of the sheath material are studied by optical microscopy(OM) and scanning electric microscopy(SEM). The result shows that interfacial shear strength increases with the increase of extrusion ratio, the maximum value of the interfacial shear strength is obtained when solid fraction of aluminum alloy is 30%,solid phase and liquid phase of the semi solid aluminum alloy are bonded with stainless steel by turns along the interface, and the aluminum alloy can not be peeled from the stainless steel completely, which means nicer bonding occurs at the interface.

  10. Influence of Refiner in ZA-12 Alloys During Centrifugal Casting Process

    Science.gov (United States)

    Jyothi, P. N.; Shailesh, Rao A.; Jagath, M. C.; Channakeshavalu, K.

    2014-05-01

    The behavior of the molten melt plays a predominant role in determining the quality cast product. In continuous casting, addition of refiner 1% (Al+Ti+B2) onto the molten metal increases its mechanical properties as a result of the nucleation within the process. In this article, the effect of refiners in the centrifugal casting process was studied. Eutectic ZA-12 alloys were taken for our experiment and cast at various rotational speeds (400 rpm, 600 rpm, and 800 rpm) with and without the addition of refiners. Rather than increase in the solidification rate as in continuous casting, these refiners diminish the solidification rate, which in turn forms an irregular-shaped cast tube. The microstructure and hardness for the entire cast specimen were discussed finally.

  11. Numerical simulation and process optimization for producing large-sized castings

    Institute of Scientific and Technical Information of China (English)

    Wang Junqing; Sun Xun; Guan Yang; Wang Penghua; Li Hailan; Bai Limei; Sun Xinzhi

    2008-01-01

    3-D velocity and temperature fields of mold filling and solidification processes of large-sized castings were calculated, and the efficiency and accuracy of numerical calculation were studied. The mold filling and solidification processes of large-sized stainless steel, iron and aluminum alloy castings were simulated by using of new scheme; their casting processes were optimized, and then applied to produce castings.

  12. Modeling of the Microstructure Evolution in Continuously Cast Al-Pb Alloys

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A numerical model is presented describing the microstructure evolution of an immiscible alloy under the continuous casting conditions. Calculations are carried out to investigate the microstructure evolution in a vertical strip cast sample of Al+5wt pct Pb alloy. The numerical results show that there exists a peak value for the supersaturation in front of the solid/liquid interface, and the minority phase droplets are nucleated in a region around this peak. Under strip casting conditions the Marangoni migration dominates the motion of droplets. This leads to an accumulation of the minority phase droplets in front of the solid/liquid interface.

  13. Optimization of Squeeze Casting Parameters for 2017 A Wrought Al Alloy Using Taguchi Method

    Directory of Open Access Journals (Sweden)

    Najib Souissi

    2014-04-01

    Full Text Available This study applies the Taguchi method to investigate the relationship between the ultimate tensile strength, hardness and process variables in a squeeze casting 2017 A wrought aluminium alloy. The effects of various casting parameters including squeeze pressure, melt temperature and die temperature were studied. Therefore, the objectives of the Taguchi method for the squeeze casting process are to establish the optimal combination of process parameters and to reduce the variation in quality between only a few experiments. The experimental results show that the squeeze pressure significantly affects the microstructure and the mechanical properties of 2017 A Al alloy.

  14. Flexural-torsional buckling behavior of aluminum alloy beams

    Institute of Scientific and Technical Information of China (English)

    Xiaonong GUO; Zhe XIONG; Zuyan SHEN

    2015-01-01

    This paper presents an investigation on the flexural-torsional buckling behavior of aluminum alloy beams (AAB). First, based on the tests of 14 aluminum alloy beams under concentrated loads, the failure pattern, load- deformation curves, bearing capacity and flexural-torsional buckling factor are studied. It is found that all the beam specimens collapsed in the flexuml-torsional buckling with excessive deformation pattern. Moreover, the span, loading location and slenderness ratio influence the flexural-torsional buckling capacity of beams significantly. Secondly, besides the experiments, a finite element method (FEM) analysis on the flexural-torsional buckling behavior of AAB is also conducted. The main parameters in the FEM analysis are initial imperfection, material property, cross-section and loading scheme. According to the analytical results, it is indicated that the FEM is reasonable to capture mechanical behavior of AAB. Finally, on the basis of the experimental and analytical results, theoretical formulae to estimate the flexural- torsional buckling capacity of AAB are proposed, which could improve the application of present codes for AAB.

  15. Stress corrosion cracking susceptibility of 7A52 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jun-jun; WANG Wei-xin; CAI Zhi-hai; ZHANG Ping

    2006-01-01

    The stress corrosion sensitivity of 7A52 aluminum alloy was investigated in the artificial sea water through slow stain rate test(SSRT). The stress corrosion cracking(SCC) susceptibility was estimated with the loss of elongation and stress corrosion sensitivity index. The results show that the susceptibility of 7A52 aluminum alloy is always high when the strain rate is in the range of 10-5-10-7s-1. It reaches the maximum at the strain rate of 8.7×10-7s-1, and the sensitivity index reaches 0.346. The characteristics of stress corrosion can be observed clearly on the fracture of tensile specimen. The process of SCC is depicted according to the fracture morphology. The SCC initiates at the edge of the specimen. Then the SCC grows rapidly because of the anode dissolving and stress concentration. When the area of specimen cannot support the tensile stress, it ruptures suddenly. The secondary cracks and quasi-cleavage surface can be found on the fracture morphology.susceptibility

  16. Investigation of Corrosion Behavior Of 6013 Aluminum Alloys For Artificial Aged Microwave Furnace

    Directory of Open Access Journals (Sweden)

    Muzaffer Erdoğan

    2014-01-01

    Full Text Available Low density and high strength aluminum alloys can be achieved today is a type of an alloy. These alloys are more resistant, particularly the aging process is the precipitate formed. In this study, increased strength 6013 aluminum alloy in a microwave furnace yaşlandırarak artificial. Volume samples in a microwave oven aging method and aging has provided a homogeneous way.6013 aluminum alloys, pure argon gas atmosphere in a microwave furnace hardness after being subjected to artificial aging process analysis, the internal structure (optical microscope, SEM, characterization of the studied. Aging of the phases, the presence server in the XRD of the samples was determined by curves. Corrosion of artificial aged samples has been analyzed by the internal structure of the phases present. Depending on the time of artificial aging of aluminum alloy 6013 samples in a microwave furnace in the mechanical properties of the sediment affected the corrosion resistance values.

  17. Thermal Decoating of Aerospace Aluminum Alloys for Aircraft Recycling

    Science.gov (United States)

    Muñiz Lerma, Jose Alberto; Jung, In-Ho; Brochu, Mathieu

    2016-06-01

    Recycling of aircraft aluminum alloys can be complex due to the presence of their corrosion protection coating that includes inorganic compounds containing Cr(VI). In this study, the characterization and thermal degradation behavior of the coating on aluminum substrates coming from an aircraft destined for recycling are presented. Elements such as Sr, Cr, Si, Ba, Ti, S, C, and O were found in three different layers by EDS elemental mapping corresponding to SrCrO4, Rutile-TiO2, SiO2, and BaSO4 with an overall particle size D 50 = 1.96 µm. The thermal degradation profile analyzed by TGA showed four different stages. The temperature of complete degradation at the fourth stage occurred at 753.15 K (480 °C) at lower heating rates. At higher heating rates and holding an isotherm at the same temperature, the residence time to fully decompose the aircraft coating has been estimated as 4.0 ± 0.2 minutes. The activation energy calculated by the Flynn-Wall-Ozawa and the modified Coats-Redfern methods for multiple fraction of decomposition showed a non-constant behavior indicating the complexity of the reaction. Finally, the concentration of Cr(VI) released to the environment during thermal decoating was obtained by UV-Vis spectroscopy. It was found that 2.6 ± 0.1 µg of Cr(VI)/mm2 of aluminum substrate could be released unless adequate particle controls are used.

  18. Thermal Decoating of Aerospace Aluminum Alloys for Aircraft Recycling

    Science.gov (United States)

    Muñiz Lerma, Jose Alberto; Jung, In-Ho; Brochu, Mathieu

    2016-03-01

    Recycling of aircraft aluminum alloys can be complex due to the presence of their corrosion protection coating that includes inorganic compounds containing Cr(VI). In this study, the characterization and thermal degradation behavior of the coating on aluminum substrates coming from an aircraft destined for recycling are presented. Elements such as Sr, Cr, Si, Ba, Ti, S, C, and O were found in three different layers by EDS elemental mapping corresponding to SrCrO4, Rutile-TiO2, SiO2, and BaSO4 with an overall particle size D 50 = 1.96 µm. The thermal degradation profile analyzed by TGA showed four different stages. The temperature of complete degradation at the fourth stage occurred at 753.15 K (480 °C) at lower heating rates. At higher heating rates and holding an isotherm at the same temperature, the residence time to fully decompose the aircraft coating has been estimated as 4.0 ± 0.2 minutes. The activation energy calculated by the Flynn-Wall-Ozawa and the modified Coats-Redfern methods for multiple fraction of decomposition showed a non-constant behavior indicating the complexity of the reaction. Finally, the concentration of Cr(VI) released to the environment during thermal decoating was obtained by UV-Vis spectroscopy. It was found that 2.6 ± 0.1 µg of Cr(VI)/mm2 of aluminum substrate could be released unless adequate particle controls are used.

  19. Crystallization of Low-alloyed Construction Cast Steel Modified with V and Ti

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2013-07-01

    Full Text Available In this paper crystallization studies of low-alloyed construction cast steel were presented for different additions of chromium, nickel and molybdenum modified with vanadium and titanium. Studies were conducted using developed TDA stand, which additionally enabled evaluation of cooling rate influence on crystallization process of investigated alloys.

  20. Fatigue Resistance of Liquid-assisted Self-repairing Aluminum Alloys Reinforced with Shape Memory Alloys

    Science.gov (United States)

    Wright, M. Clara; Manuel, Michele; Wallace, Terryl

    2013-01-01

    A self-repairing aluminum-based composite system has been developed using a liquid-assisted healing theory in conjunction with the shape memory effect of wire reinforcements. The metal-metal composite was thermodynamically designed to have a matrix with a relatively even dispersion of a low-melting eutectic phase, allowing for repair of cracks at a predetermined temperature. Additionally, shape memory alloy (SMA) wire reinforcements were used within the composite to provide crack closure. Investigators focused the research on fatigue cracks propagating through the matrix in order to show a proof-of-concept Shape Memory Alloy Self-Healing (SMASH) technology for aeronautical applications.