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Sample records for es steel sheets

  1. Steel Sheet Pile Walls in Soft Soil

    NARCIS (Netherlands)

    Kort, D.A.

    2002-01-01

    For almost a century, steel sheet pile walls are applied worldwide as earth retaining structures for excavations and quay walls. Within the framework of the development of European structural codes for Civil Engineering works, the Eurocodes, Eurocode 3 Part 5 for design of steel sheet pile walls was

  2. Milled Die Steel Surface Roughness Correlation with Steel Sheet Friction

    DEFF Research Database (Denmark)

    Berglund, J.; Brown, C.A.; Rosén, B.-G.

    2010-01-01

    This work investigates correlations between the surface topography ofmilled steel dies and friction with steel sheet. Several die surfaces were prepared by milling. Friction was measured in bending under tension testing. Linear regression coefficients (R2) between the friction and texture...... characterization parameters were tested. None of the height, spacing, material volume, void or segmentation parameters showed good correlations. Developed area, rms surface gradient, relative area and complexity showed strong correlations (R2 > 0.7). For area-scale fractal complexity the correlation increases...

  3. Construction of Steel Pipe Sheet Piles with Newly Developed Joint ...

    African Journals Online (AJOL)

    H-joint in steel pipe sheet piles (SPSP) is introduced and developed, the joint is made by welding a cylindrical steel pile on either side of an H steel section, welding is continuous along their lengths therefore it is completely waterproof with high strength; the two connected piles are installed simultaneously hence short ...

  4. Zinc coated sheet steel for press hardening

    Science.gov (United States)

    Ghanbari, Zahra N.

    Galvanized steels are of interest to enhance corrosion resistance of press-hardened steels, but concerns related to liquid metal embrittlement have been raised. The objective of this study was to assess the soak time and temperature conditions relevant to the hot-stamping process during which Zn penetration did or did not occur in galvanized 22MnB5 press-hardening steel. A GleebleRTM 3500 was used to heat treat samples using hold times and temperatures similar to those used in industrial hot-stamping. Deformation at both elevated temperature and room temperature were conducted to assess the coating and substrate behavior related to forming (at high temperature) and service (at room temperature). The extent of alloying between the coating and substrate was assessed on undeformed samples heat treated under similar conditions to the deformed samples. The coating transitioned from an α + Gamma1 composition to an α (bcc Fe-Zn) phase with increased soak time. This transition likely corresponded to a decrease in availability of Zn-rich liquid in the coating during elevated temperature deformation. Penetration of Zn into the substrate sheet in the undeformed condition was not observed for any of the processing conditions examined. The number and depth of cracks in the coating and substrate steel was also measured in the hot-ductility samples. The number of cracks appeared to increase, while the depth of cracks appeared to decrease, with increasing soak time and increasing soak temperature. The crack depth appeared to be minimized in the sample soaked at the highest soak temperature (900 °C) for intermediate and extended soak times (300 s or 600 s). Zn penetration into the substrate steel was observed in the hot-ductility samples soaked at each hold temperature for the shortest soak time (10 s) before being deformed at elevated temperature. Reduction of area and elongation measurements showed that the coated sample soaked at the highest temperature and longest soak time

  5. 75 FR 81308 - Stainless Steel Sheet And Strip From Germany, Italy, Japan, Korea, Mexico, And Taiwan

    Science.gov (United States)

    2010-12-27

    ... COMMISSION Stainless Steel Sheet And Strip From Germany, Italy, Japan, Korea, Mexico, And Taiwan AGENCY... countervailing duty order on stainless steel sheet and strip from Korea and antidumping duty orders on stainless... on stainless steel sheet and strip from Korea and/or the antidumping duty orders on stainless steel...

  6. Fatigue characteristics of dual-phase steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Onn, Irwan Herman; Ahmad, Norhayati; Tamin, Mohd Nasir [Universiti Teknologi Malaysia, Skudai (Malaysia)

    2015-01-15

    Fatigue characteristics of dual-phase steel sheets, commonly used in automobile body construction were established. For this purpose, a series of fatigue tests, each at constant stress amplitude were conducted on 1.2 mm-thick, dual-phase DP600 steel sheet specimens with two different load ratios of minimum-to-maximum stress, R = 0.1 and -1. The resulting fatigue behavior is expressed in terms of fatigue strength-life (S-N) curves. Fatigue behavior of the steel sheets in the high-cycle fatigue region can be represented by Basquin's equation with coefficient and exponent value of 921.2 and 0.093, respectively. An endurance limit of 255 MPa is observed. In addition, fatigue strengths of the dual-phase steel sheets display lower magnitude than their bulk counterparts. Effect of mean stress on fatigue behavior of the steel sheets is well predicted by Walker's model. Exponential calibration factor is introduced to the models by SWT, Goodman and Morrow with comparable prediction to the Walker's model.

  7. Laser welding of Zn-coated sheet steels

    Science.gov (United States)

    Graham, Marianne P.; Kerr, Hugh W.; Weckman, David C.

    1996-04-01

    Compared to other welding processes, laser welding of sheet steels coated with various zinc- rich layers (galvanized, electrogalvanized, galvannealed, etc.) can permit weight reduction of automobiles plus increase in productivity. Some instances of laser welding of such coated steels have been reported. However, wider applications of lasers for this purpose are hampered by the low boiling temperature of zinc compared to the melting temperature of steel. During laser welding in the lap-joint configuration, the presence of vaporized zinc between the steel sheets often leads to expulsion of the weld metal or considerably weld porosity. Attempts to overcome this problem using Nd:YAG laser welding are reviewed. For the lap-joint configuration, techniques examined include provision of a gap between the sheets, use of geometrical solutions such as concave or convex surfaces, and pulsing or modulating the laser waveform. The effects on weld quality of power density, pulse time and pulse shaping (for pulsed welding), the coating type and weight, the location of the beam axis and beam focus with respect to the sheet surface(s) and the joint geometry (lap and edge) have been examined. The results provide insight into the weldability of coated sheet steels by the laser welding process as well as better assessment of viable approaches to this problem.

  8. Dynamic characteristics of automotive steel sheets

    Directory of Open Access Journals (Sweden)

    M. Mihaliková

    2016-10-01

    Full Text Available The aim of this experimental research was to perform an analysis of deformation characteristics on two different types of steel: IF steel, and micro-alloyed steel were used automotive industry. For that purpose changes of properties of these materials were carried out by static 10-3 · s-1 and dynamic 103 · s-1 strain rate assess its plastic properties. Vickers micro hardness test was carried out by the static and dynamic loading condition and describes different hardness distribution. The higher strain hardening of materials was obtained too that was confirmed by distribution of dislocations.

  9. The stretch zone of automotive steel sheets

    Indian Academy of Sciences (India)

    This study brings new material properties which are necessary for modelling and simulation the crash behaviour of automotive sheets. ... The specimens were loaded by eccentric tension on a tensile testing machine (FP 100/1) at two crosshead-rates: 0.0217 and 2.17 mm/s. The videoextensometry technique enables us to.

  10. 75 FR 30437 - Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan

    Science.gov (United States)

    2010-06-01

    ... COMMISSION Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan AGENCY... countervailing duty order on stainless steel sheet and strip from Korea and the antidumping duty orders on stainless steel sheet and strip from Germany, Italy, Japan, Korea, Mexico, and Taiwan. SUMMARY: The...

  11. 76 FR 46323 - Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan

    Science.gov (United States)

    2011-08-02

    ... COMMISSION Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan... U.S.C.1675(c)), that revocation of the antidumping duty orders on stainless steel sheet and strip... revocation of the countervailing duty order on stainless steel sheet and strip from Korea and revocation of...

  12. 75 FR 59744 - Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan

    Science.gov (United States)

    2010-09-28

    ... COMMISSION Stainless Steel Sheet and Strip From Germany, Italy, Japan, Korea, Mexico, and Taiwan AGENCY... five-year reviews concerning the countervailing duty order on stainless steel sheet and strip from Korea and the antidumping duty orders on stainless steel sheet and strip from Germany, Italy, Japan...

  13. 76 FR 13357 - Stainless Steel Sheet and Strip in Coils From Mexico; Correction Notice to Amended Final Results...

    Science.gov (United States)

    2011-03-11

    ... International Trade Administration Stainless Steel Sheet and Strip in Coils From Mexico; Correction Notice to... administrative review for stainless steel sheet and strip in coils from Mexico. See Stainless Steel Sheet and.... See Stainless Steel Sheet and Strip in Coils from Mexico; Final Results of Antidumping Duty...

  14. 76 FR 18518 - Stainless Steel Sheet and Strip in Coils From Mexico: Rescission of Antidumping Duty...

    Science.gov (United States)

    2011-04-04

    ... International Trade Administration Stainless Steel Sheet and Strip in Coils From Mexico: Rescission of... stainless steel sheet and strip in coils from Mexico. The period of review is July 1, 2009, through June 30... American Stainless, and AK Steel Corporation (collectively ``petitioners''), we are now rescinding this...

  15. CO2 Laser Cutting of Hot Stamping Boron Steel Sheets

    Directory of Open Access Journals (Sweden)

    Pasquale Russo Spena

    2017-10-01

    Full Text Available This study investigates the quality of CO2 laser cutting of hot stamping boron steel sheets that are employed in the fabrication of automotive body-in-white. For this purpose, experimental laser cutting tests were conducted on 1.2 mm sheets at varying levels of laser power, cutting speed, and oxygen pressure. The resulting quality of cut edges was evaluated in terms of perpendicularity tolerance, surface irregularity, kerf width, heat affected zone, and dross extension. Experimental tests were based on a L9(34 orthogonal array design, with the effects of the process parameters on the quality responses being determined by means of a statistical analysis of variance (ANOVA. Quadratic mathematical models were developed to determine the relationships between the cutting parameters and the quality responses. Finally, a routine based on an optimization criterion was employed to predict the optimal setting of cutting factors and its effect on the quality responses. A confirmation experiment was conducted to verify the appropriateness of the optimization routine. The results show that all of the examined process parameters have a key role in determining the cut quality of hot stamping boron steel sheets, with cutting speed and their interactions having the most influencing effects. Particularly, interactions can have an opposite behavior for different levels of the process parameters.

  16. Correlation of titanium content and core loss in non-oriented electrical steel sheets

    OpenAIRE

    D. Steiner Petrovič; M. Jenko; A. Jaklič; A. Čop

    2010-01-01

    In this study the correlation between the titanium content of steel and the core loss of non-oriented electrical steel sheets was determined. The core loss and titanium content of steel have a weak, but positive, correlation. The core loss was found to increase with an increasing titanium content. The study included a statistical analysis of an industrial data set and a metallographic analysis of the titanium inclusions. The analyzed titanium inclusions in the electrical steel sheets containi...

  17. IMPACT OF STRAIN RATE ON MICROALLOYED STEEL SHEET BREAKING

    Directory of Open Access Journals (Sweden)

    Mária Mihaliková

    2014-08-01

    Full Text Available Strain rate is a significant external factor and its influence on material behavior in forming process is a function of its internal structure. The contribution is analysis of the impact of loading rate from 1.6 x 10-4 ms-1 to 24 ms-1 to changes in the fracture of steel sheet used for bodywork components in cars. Experiments were performed on samples taken from HC420LA grade strips produced by cold rolling and hot dip galvanizing. Material strength properties were compared based on measured values, and changes to fracture surface character were observed.

  18. The Effect of Strain Rate on the Mechanical Properties of Automotive Steel Sheets

    Directory of Open Access Journals (Sweden)

    Miroslav Német

    2013-01-01

    Full Text Available The automotive industry is currently seeking detailed information about various types of materials and their behavior under dynamic loading. Dynamic tensile testing of sheet steels is growing in importance. The experimental dynamic tensile technique depends on the strain rate. Each type oftest serves for a specific range of strain rates, and provides specific types of information. This workdeals with the influence of the strain rate on the mechanical properties of automotive steel sheets.Three different types of steel: IF steel, DP steel, and micro-alloyed steel (S 460 were used to compare static and dynamic properties.

  19. Steel Sheet Piles – Applications and Elementary Design Issues

    Science.gov (United States)

    Sobala, Dariusz; Rybak, Jarosław

    2017-10-01

    High-intensity housing having been carried out in town’s centres causes that many complex issues related to earthworks and foundations must be resolved. Project owners are required to ensure respective number of parking bays, which in turn demands 2-3 storeys of underground car parks. It is especially difficult to fulfil in dense buildings of old town areas where apart from engineering problems, very stringent requirements of heritage conservator supervision are also raised. The problems with ensuring stability of excavation sidewalls need to be, at the same time, dealt with analysis of foundations of neighbouring structures, and possible strengthening them at the stages of installing the excavation protection walls, progressing the excavations and constructing basement storeys. A separate problem refers to necessity of constructing underground storeys below the level of local groundwater. This requires long-term lowering of water table inside excavation while at possibly limited intervention in hydrological regime beyond the project in progress. In river valleys such “hoarding off” the excavation and cutting off groundwater leads to temporary or permanent disturbances of groundwater run-off and local swellings. Traditional way to protect vertical fault and simultaneously to cut-off groundwater inflow consists in application of steel sheet pilings. They enable to construct monolithic reinforced concrete structures of underground storeys thus ensuring both their tightness and high rigidity of foundation. Depending on situation, steel sheet pilings can be in retrieving or staying-in-place versions. This study deals with some selected aspects of engineering design and fabrication of sheet piling for deep excavations and underground parts of buildings.

  20. 77 FR 32998 - Tin- and Chromium-Coated Steel Sheet From Japan

    Science.gov (United States)

    2012-06-04

    ... COMMISSION Tin- and Chromium-Coated Steel Sheet From Japan Determination On the basis of the record \\1... antidumping duty order on tin- and chromium-coated steel sheet from Japan would be likely to lead to... from Japan: Investigation No. 731-TA-860 (Second Review). By order of the Commission. Issued: May 29...

  1. Design recommendations for long span composite slabs with deep profiled steel sheets

    NARCIS (Netherlands)

    Brekelmans, J.W.P.M.; Daniels, B.J.; Hove, B.W.E.M. van; Koukkari, H.; Stark, J.W.B.; Schuurman, R.G.

    1997-01-01

    As part of the ECSC research project `Steel intensive shallow floor construction', design recommendations for long span composite slabs with deep profiled steel deck have been drafted. These deep profiled steel sheets have depths of at least 200 mm. Test results and design recommendations are

  2. 78 FR 14270 - Stainless Steel Sheet and Strip in Coils From Mexico: Notice of Settlement of NAFTA Proceedings

    Science.gov (United States)

    2013-03-05

    ... International Trade Administration Stainless Steel Sheet and Strip in Coils From Mexico: Notice of Settlement of... July 27, 1999, the Department published the antidumping duty order on stainless steel sheet and strip in coils from Mexico (SSSS from Mexico). See Stainless Steel Sheet and Strip in Coils from Mexico, 64...

  3. Three-Sheet Spot Welding of Advanced High-Strength Steels

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Friis, Kasper Storgaard; Zhang, W.

    2011-01-01

    The automotive industry has introduced the three-layer weld configuration, which represents new challenges compared to normal two-sheet lap welds. The process is further complicated by introducing high-strength steels in the joint. The present article investigates the weldability of thin, low....... The weld mechanisms are analyzed numerically and compared with metallographic analyses showing how the primary bonding mechanism between the thin, low-carbon steel sheet and the thicker sheet of high-strength steel is solid-state bonding, whereas the two high-strength steels are joined by melting, forming...... a weld nugget at their mutual interface. Despite the absence of the typical fusion nugget through the interface between the low-carbon steel and high-strength steel, the weld strengths obtained are acceptable. The failure mechanism in destructive testing is ductile fracture with plug failure....

  4. Measurement research on magnetic properties of electrical sheet steel under different temperature, harmonic and dc bias

    Directory of Open Access Journals (Sweden)

    Dezhi Chen

    2017-05-01

    Full Text Available The iron core of large power transformer is mainly composed of electrical sheet steel, which is easily affected by temperature, harmonic, and DC bias. Therefore, it is necessary to measure the magnetic properties of electrical sheet steel under different temperature, harmonic and DC Bias. This paper presents the experiment measurement system for the 30ZH120 electrical steel sheet. The B-H magnetization curve, permeability, and loss curve under different temperature, different harmonic, and different DC bias are given, respectively. The simulation of transformer is carried out by using measuring result under DC bias. The presented research provides a reference for optimizing the design of power transformer.

  5. Correlation of titanium content and core loss in non-oriented electrical steel sheets

    Directory of Open Access Journals (Sweden)

    D. Steiner Petrovič

    2010-01-01

    Full Text Available In this study the correlation between the titanium content of steel and the core loss of non-oriented electrical steel sheets was determined. The core loss and titanium content of steel have a weak, but positive, correlation. The core loss was found to increase with an increasing titanium content. The study included a statistical analysis of an industrial data set and a metallographic analysis of the titanium inclusions. The analyzed titanium inclusions in the electrical steel sheets containing 0,006 mas.% Ti and 0,008 mas.% Ti were complex oxycarbonitrides, complex TiC and complex Ti(C,N.

  6. Multi objective Taguchi optimization approach for resistance spot welding of cold rolled TWIP steel sheets

    Science.gov (United States)

    Tutar, Mumin; Aydin, Hakan; Bayram, Ali

    2017-08-01

    Formability and energy absorption capability of a steel sheet are highly desirable properties in manufacturing components for automotive applications. TWinning Induced Plastisity (TWIP) steels are, new generation high Mn alloyed steels, attractive for the automotive industry due to its outstanding elongation (%40-45) and tensile strength (~1000MPa). So, TWIP steels provide excellent formability and energy absorption capability. Another required property from the steel sheets is suitability for manufacturing methods such as welding. The use of the steel sheets in the automotive applications inevitably involves welding. Considering that there are 3000-5000 welded spots on a vehicle, it can be interpreted that one of the most important manufacturing method is Resistance Spot Welding (RSW) for the automotive industry. In this study; firstly, TWIP steel sheet were cold rolled to 15% reduction in thickness. Then, the cold rolled TWIP steel sheets were welded with RSW method. The welding parameters (welding current, welding time and electrode force) were optimized for maximizing the peak tensile shear load and minimizing the indentation of the joints using a Taguchi L9 orthogonal array. The effect of welding parameters was also evaluated by examining the signal-to-noise ratio and analysis of variance (ANOVA) results.

  7. Internal force analysis of steel sheet pile cofferdam by considering the construction "path" effect

    Directory of Open Access Journals (Sweden)

    Dong LIANG

    2016-04-01

    Full Text Available In the process of installing inner support, the force loaded on the steel sheet pile is continuous, that is, the installation of inner support always happens after the accumulative deformation caused by inside and outside pressure difference of the steel sheet pile cofferdam. Taking the steel sheet pile cofferdam construction of a specially long span bridge as example, the paper puts forwards a spatial model of steel sheet pile cofferdam considering the construction “path” based on ANSYS. The model calculation result and the actual measurement result are compared. The results show that the model based on considering the “path” effects has a more similar calculating result with the measured value.

  8. Experimental characterization of microstructure development during loading path changes in bcc sheet steels

    NARCIS (Netherlands)

    Clausmeyer, T.; Gerstein, G.; Bargmann, S.; Svendsen, B.; van den Boogaard, Antonius H.; Zillmann, B.

    2013-01-01

    Interstitial free sheet steels show transient work hardening behavior, i.e., the Bauschinger effect and cross hardening, after changes in the loading path. This behavior affects sheet forming processes and the properties of the final part. The transient work hardening behavior is attributed to

  9. Testing new tribo-systems for sheet metal forming of advanced high strength steels and stainless steels

    DEFF Research Database (Denmark)

    Bay, Niels; Ceron, Ermanno

    2014-01-01

    Testing of new tribo-systems in sheet metal forming has become an important issue due to new legislation, which forces industry to replace current, hazardous lubricants. The present paper summarizes the work done in a recent PhD project at the Technical University of Denmark on the development...... of a methodology for off-line testing of new tribo-systems for advanced high strength steels and stainless steels. The methodology is presented and applied to an industrial case, where different tribo-systems are tested. A universal sheet tribotester has been developed, which can run automatically repetitive...

  10. The Effect of Local Heating by Laser Irradiation for Aluminum, Deep Drawing Steel and Copper Sheets in Incremental Sheet Forming

    Science.gov (United States)

    Lehtinen, Pekka; Väisänen, Tapio; Salmi, Mika

    Incremental sheet forming is a technique where a metal sheet is formed into a product usually by a CNC-controlled (Computer Numerical Control) round tipped tool. The part is formed as the tool indents into the sheet and follows a contour of the desired product. In single point incremental forming (SPIF) there is no need for tailored tools and dies, since the process requires only a CNC machine, a clamping rig and a simple tool. The effect of applying local heating by laser irradiation from the bottom side of the metal sheet is investigated with a SPIF approach. Using a laser light source for local heating should increase the material ductility and decrease material strength, and thus, increase the formability. The research was performed using 0.50-0.75 mm thick, deep drawing steel, aluminum and copper sheets. The forming was done with a round tipped tool, whose tip diameter was 4 mm. In order to achieve selective heating, a 1 kW fiber laser was attached to a 3-axis stepper motor driven CNC milling machine. The results show that the applied heating increased the maximum achievable wall angle of aluminum and copper products. However, for the steel sheets the local heating reduced the maximum achievable wall angle and increased the surface roughness.

  11. Application technologies for effective utilization of advanced high strength steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Suehiro, Masayoshi, E-mail: suehiro.kp5.masayoshi@jp.nssmc.com [Steel Research Laboratories, Nippon Steel and Sumitomo Metal Corporation, 20-1 Shintomi, Futtsu, Chiba 293-8511 (Japan)

    2013-12-16

    Recently, application of high strength steel sheets for automobiles has increased in order to meet a demand of light weighting of automobiles to reduce a carbon footprint while satisfying collision safety. The formability of steel sheets generally decreases with the increase in strength. Fracture and wrinkles tend to occur easily during forming. The springback phenomenon is also one of the issues which we should cope with, because it makes it difficult to obtain the desired shape after forming. Advanced high strength steel sheets with high formability have been developed in order to overcome these issues, and at the same time application technologies have been developed for their effective utilization. These sheets are normally used for cold forming. As a different type of forming, hot forming technique has been developed in order to produce parts with ultra high strength. In this report, technologies developed at NSSMC in this field will be introduced.

  12. Connection in Joints for Thin-Walled Steel Sections and Sheeting

    Directory of Open Access Journals (Sweden)

    M.A. Othuman Mydin

    2014-07-01

    Full Text Available Thin-walled cold-formed members are thin, this will give rise to behavioural phenomena, which are not usually encountered in the more familiar hot-rolled sections. When compared to hot-rolled steel sections, cold-formed thin-walled steel sections are more likely to fail in local buckling, distortional buckling, various global buckling and shear buckling. This paper will discuss types of connection in Jjoints for coldformed thin-walled sections and steel sheeting. Bolts, screws, blind rivets or cartridge fired pins are commonly used in joints for coldformed thin-walled sections or steel sheet connections. Fasteners in light gauge steel tend to be relatively less stiff than their counterparts in heavier construction so that connection flexibility can be significant in certain assemblies. Furthermore, as in any load-bearing structure, it is important that connections are not brittle and this implies that there should be adequate deformation capacity.

  13. Experimental Analysis of the Feasibility of Shaving Process Applied for High-Strength Steel Sheets

    Directory of Open Access Journals (Sweden)

    Wiriyakorn Phanitwong

    2016-01-01

    Full Text Available In recent years, the engineered materials were developed to improve their mechanical properties. A high-strength steel sheet is one of them, developed to serve the requirement of reducing weight of vehicles. Therefore, as a new material, many researches have been carried out to examine the use of sheet metal forming process applied for high-strength steel sheet. However, the feasibility of shaving process applied for it has not been investigated yet. In the present study, this feasibility was revealed by using experiments on two types of high-strength steel sheets: SAPH 440 and SPFH 590Y (JIS. The relationship between shaved surface feature and shearing clearance of high-strength steel sheets corresponded well with those of their conventional metal sheets. However, due to the high ultimate strength of these materials, it was revealed in this present study that there were not any suitable conditions of shaving process that could be applied to achieve the requirements of smooth cut surface overall material thickness.

  14. The rolling performance of Fe-6.5 wt.% Si sheets edged with stainless steel

    Science.gov (United States)

    Zhang, B.; Ye, F.; Liang, Y. F.; Shi, X. J.; Lin, J. P.

    2017-10-01

    Compared with common electrical steel, high silicon electrical steel (Fe-6.5 wt.% Si alloy) exhibits excellent soft magnetic properties and a wide application prospect in high frequency electromagnetic fields. In the process of cold rolling Fe-6.5 wt.% Si alloy, edge-crack often occurs on the sheets due to the inadequate ductility and limited formability. It was found that the Fe-6.5 wt.% Si alloy sheet edged with 304 stainless steel by laser welding show an improved rolling performance. The composite sheet could be cold rolled to a thickness of 0.07 mm without observed edge cracks. The mechanical property of the edging material should be in an appropriate window in reference to that of the Fe-6.5 wt.% Si alloy.

  15. Microstructures and Properties of Medium Manganese Sheet Steels - Strategies and Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Rana, Radhakanta [CSM/ASPPRC; De Moor, Emmanuel [CSM/ASPPRC; Speer, John G [CSM/ASPPRC; Matlock, David K [CSM/ASPPRC

    2015-10-06

    Medium manganese steels, with 3 to 10 wt pct Mn, have been shown to be capable of being thermally-processed to produce sheet products with a variety of strength-ductility combinations and thus are receiving considerable attention as candidates for 3rd generation advanced high strength steels (3GAHSS). The steels typically contain refined microstructures with characteristic microstructural dimensions of 1 to 2 µm and consist of significant amounts of retained austenite in a fine grained ferritic matrix. Strategies for development of medium manganese steels are reviewed and results of recent property predictions based on composite modeling are presented. The importance of controlling austenite stability is illustrated with data on medium Mn (7 and 10 wt pct.), low carbon (0.1 and 0.15 wt pct) steels. Important forming variables (strain, strain rate, and temperature) are discussed, along with a consideration of yield point elongation, present in many medium Mn steels.

  16. Increments of plastic strain and hardness HV10 of automotive steel SHEETS

    Directory of Open Access Journals (Sweden)

    M. Mihaliková

    2012-10-01

    Full Text Available The present paper deals with measurements of the increments of strain and hardness HV10 on automotive steel sheets. The car body manufacture trends are focused, in particular, on high energy absorption capability. In the manufacture of a car body, there are requirements for high plasticity and homogeneity of the pressed sheets. The measurements were made on DP steel, micro-alloyed steel, and IF steel. The increments of strain were measured around V notches. The specimens were scanned using a video-extensometer technique with a CCD camera. The result was strain increment maps, constructed using the Matlab software. The hardness HV10 was measured on the failed specimens around the notches. 3D hardness distribution maps were made from the measured values of HV10.

  17. Determination of the forming limit diagram of zinc electro-galvanized steel sheets

    Directory of Open Access Journals (Sweden)

    W. Fracz

    2012-04-01

    Full Text Available Forming limit curves (FLC of deep drawing steel sheets have been determined experimentally and calculated on the base of the material tensile properties following the Hill, Swift, Marciniak-Kuczyński and Sing-Rao methods. Only the FLC modeled from a singly linear forming limit stress curve exhibits good consistence with experimental curve. It was established that a linearized limit stress locus describes adequately the actual localized neck conditions for the material chosen in this study. The quantitative X-ray microanalysis of the Fe contents in the sheet surface layer composition was used to determine cracking limit curve (CLC of electro-galvanized steel sheet. The change in zinc layer (and base sheet metal thickness was used as a criteria in calculation of the CLC.

  18. The analysis of spot welding joints of steel sheets with closed profile by ultrasonic method

    Directory of Open Access Journals (Sweden)

    Dariusz Ulbrich

    2015-11-01

    Full Text Available Resistance spot welding is widely used in the fabrication of vehicle bodies and parts of their equipment. The article presents the methodology and the results of non-destructive ultrasonic testing of resistance spot welded joints of thin steel sheet with closed profile. Non-destructive test results were verified on the basis of welded joint area after destructive testing. The obtained results were used to develop an assessment technique for spot welded joints of closed profile with steel sheet, which could be used in factories employing such joints. In addition, the article makes comparison between the costs of the developed assessment technique and currently used destructive method.

  19. Mechanical Behavior of Steel Fiber-Reinforced Concrete Beams Bonded with External Carbon Fiber Sheets.

    Science.gov (United States)

    Gribniak, Viktor; Tamulenas, Vytautas; Ng, Pui-Lam; Arnautov, Aleksandr K; Gudonis, Eugenijus; Misiunaite, Ieva

    2017-06-17

    This study investigates the mechanical behavior of steel fiber-reinforced concrete (SFRC) beams internally reinforced with steel bars and externally bonded with carbon fiber-reinforced polymer (CFRP) sheets fixed by adhesive and hybrid jointing techniques. In particular, attention is paid to the load resistance and failure modes of composite beams. The steel fibers were used to avoiding the rip-off failure of the concrete cover. The CFRP sheets were fixed to the concrete surface by epoxy adhesive as well as combined with various configurations of small-diameter steel pins for mechanical fastening to form a hybrid connection. Such hybrid jointing techniques were found to be particularly advantageous in avoiding brittle debonding failure, by promoting progressive failure within the hybrid joints. The use of CFRP sheets was also effective in suppressing the localization of the discrete cracks. The development of the crack pattern was monitored using the digital image correlation method. As revealed from the image analyses, with an appropriate layout of the steel pins, brittle failure of the concrete-carbon fiber interface could be effectively prevented. Inverse analysis of the moment-curvature diagrams was conducted, and it was found that a simplified tension-stiffening model with a constant residual stress level at 90% of the strength of the SFRC is adequate for numerically simulating the deformation behavior of beams up to the debonding of the CFRP sheets.

  20. The analysis of spot welding joints of steel sheets with closed profile by ultrasonic method

    OpenAIRE

    Dariusz Ulbrich; Jakub Kowalczyk; Marian Jósko; Jarosław Selech

    2015-01-01

    Resistance spot welding is widely used in the fabrication of vehicle bodies and parts of their equipment. The article presents the methodology and the results of non-destructive ultrasonic testing of resistance spot welded joints of thin steel sheet with closed profile. Non-destructive test results were verified on the basis of welded joint area after destructive testing. The obtained results were used to develop an assessment technique for spot welded joints of closed profile with steel shee...

  1. Magnetic Properties and Structure of Non-Oriented Electrical Steel Sheets after Different Shape Processing

    Czech Academy of Sciences Publication Activity Database

    Bulín, Tomáš; Švábenská, Eva; Hapla, Miroslav; Ondrůšek, Č.; Schneeweiss, Oldřich

    2017-01-01

    Roč. 131, č. 4 (2017), s. 819-821 ISSN 0587-4246. [CSMAG 2016 - Czech and Slovak Conference on Magnetism /16./. Košice, 13.06.2016-17.06.2016] R&D Projects: GA TA ČR(CZ) TE02000232 Institutional support: RVO:68081723 Keywords : Magnetic properties * Silicon steel * Steel sheet Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.469, year: 2016

  2. Tool degradation during sheet metal forming of three stainless steel alloys

    DEFF Research Database (Denmark)

    Wadman, Boel; Nielsen, Peter Søe; Wiklund, Daniel

    2010-01-01

    To evaluate if changes in tool design and tool surface preparation are needed when low-Ni stainless steels are used instead of austenitic stainless steels, the effect on tool degradation in the form of galling was investigated with three different types of stainless steel. The resistance to tool...... degradation was analysed by the strip reduction test, simulating resistance to galling during ironing. It was shown that the surface condition of both the tools and the sheet metal was of importance to the galling resistance. Numerical simulations of the experimental tests were compared with the experimental...

  3. Influence of heat treatment on mechanical property of steel hollow sphere and its sheet construction

    Science.gov (United States)

    Yoshida, Yoshinori; Ozawa, Sho

    2017-10-01

    Heat treatments, water quenching and annealing, are performed on the metallic hollow spheres (MHS) made from steel with 4.0 mm in outer diameter. They are pierced then put on a piece of tungsten alloy wire for making a MHS thread. The thread is set in between two neighboring warps of the tungsten alloy and the thread is placed in a reticular pattern. The MHS fabric sheet which has plain weave structure is produced by the weaving process. Furthermore, a sandwich construction of the sheet with 2 sheets of aluminum plate. The influence of the heat treatments on difference of mechanical and energy absorption property are evaluated by mean of compression test for the sheet along with the thickness direction. In addition, an aluminum pipe is filled with a heat treated MHS sheet and compression test is performed for the pipe along the radial direction. Its difference of compression load and energy consumption property is investigated.

  4. Wear of soft tool materials in sliding contact with zinc coated steel sheet

    NARCIS (Netherlands)

    van der Heide, Emile; Burlat, M.; Bolt, P.J.; Schipper, Dirk J.

    2003-01-01

    In order to reduce costs of tooling for press operations, efforts are made to use alternative tool materials like wood or plastic. Friction and wear characteristics in sliding contact with zinc-coated steel sheet could, however, limit the applicability of these tool materials for automotive

  5. Tribological study in roll forming of lean duplex stainless steel sheets

    DEFF Research Database (Denmark)

    Nielsen, Peter Søe; Nielsen, Morten Strogaard; Bay, Niels

    2012-01-01

    focus on tribological issues are galling and pick-up formation as well as tool life in roll forming of stainless duplex steel sheets. The roll forming process is exemplified by production of an s-shaped profile used in interlock carcass production for flexible pipes used in off-shore oil extraction...

  6. THE IMPACT OF SELECTED TECHNOLOGICAL AND MATERIAL PARAMETERS ON THE STRENGTH OF ADHESIVE STEEL SHEETS JOINTS

    Directory of Open Access Journals (Sweden)

    Anna Rudawska

    2017-06-01

    Full Text Available The following paper analyses selected problems regarding the impact of technological parameters and type of adherend material on the strength of adhesive-bonded steel sheet joints. The subject of the test was a single-lap adhesive joint of S235JR steel sheet. Joints were formed on two types of substrates: with or without corrosion products on the surface. The surface of steel sheet adherends was pre-treated with three cleaning solutions: acetone, Wiko industrial degreasing agent and Cortanin F anti-corrosion agent, depend-ing on the state of the surface. Adhesive joints were formed with Epidian 53/ET/100:15 epoxy adhesive. The formed joints were subjected to one of three ageing variants: 14 days, two months and 3 months, which were followed by destructive testing to determine the shear strength of joints. The analysis of results ob-tained in tests indicates that the strength performance of adhesive joints of corrosion-free adherends was characterised by higher values than in corroded steel sheets, regardless of ageing time.

  7. Testing and modelling of new tribo-systems for industrial sheet forming of stainless steels

    DEFF Research Database (Denmark)

    Nielsen, Peter Søe; Friis, Kasper Storgaard; Bay, Niels

    2011-01-01

    Sheet metal forming of stainless steels is known to be tribologically demanding. To ensure satisfactory production without pick-up and galling, lubrication with environmentally hazardous chlorinated paraffin oil is normally required and in the most severe cases combined with ceramic tool coatings...

  8. Cyclic shear behavior of austenitic stainless steel sheet

    NARCIS (Netherlands)

    Geijselaers, Hubertus J.M.; Bor, Teunis Cornelis; Hilkhuijsen, P.; van den Boogaard, Antonius H.

    2015-01-01

    An austenitic stainless steel has been subjected to large amplitude strain paths containing a strain reversal. During the tests, apart from the stress and the strain also magnetic induction was measured to monitor the transformation of austenite to martensite. From the in-situ magnetic induction

  9. Transformation in austenitic stainless steel sheet under different loading directions

    NARCIS (Netherlands)

    van den Boogaard, Antonius H.; Krauer, J.; Hora, P.

    2011-01-01

    The stress-strain relation for austenitic stainless steels is based on 2 main contributions: work hardening and a phase transformation from austenite to martensite. The transformation is highly temperature dependent. In most models for phase transformation from austenite to martensite, the stress

  10. Transformation in Austenitic Stainless Steel Sheet under Different Loading Directions

    NARCIS (Netherlands)

    van den Boogaard, Antonius H.; Krauer, J.; Hora, P.

    2011-01-01

    The stress-strain relation for austenitic stainless steels is based on 2 main contributions: work hardening and a phase transformation from austenite to martensite. The transformation is highly temperature dependent. In most models for phase transformation from austenite to martensite, the stress

  11. 76 FR 31633 - Tin- and Chromium-Coated Steel Sheet from Japan; Institution of a Five-Year Review Concerning the...

    Science.gov (United States)

    2011-06-01

    ... COMMISSION Tin- and Chromium-Coated Steel Sheet from Japan; Institution of a Five-Year Review Concerning the Antidumping Duty Order on Tin- and Chromium-Coated Steel Sheet from Japan AGENCY: United States International... whether revocation of the antidumping duty order on tin- and chromium-coated steel sheet from Japan would...

  12. Development of strategic surface topographies for lubrication in sheet forming of stainless steel

    DEFF Research Database (Denmark)

    Nilsson, Morten; Olsson, David Dam; Petrushina, Irina

    2004-01-01

    Strategic stainless steel surfaces have been developed by which the tribological properties are significantly improved for sheet metal forming compared to as received surfaces. The improvements have been achieved by modification of the surface in order to promote micro-plasto hydrodynamic...... lubrication by increasing the ratio of closed lubricant pockets and modifying the pocket geometry. These factors influence the retention and subsequently escape of lubricant during forming thus enhancing lubricant permeability to the contact between flattened work piece asperities and contacting tool....... The technique, which has been developed, is based on an electrochemical treatment changing the topography of the stainless steel surface. Comparative testing of the new surface topographies in ironing and deep drawing of stainless steel sheet shows significant improvements and possibilities of replacing...

  13. AISI/DOE Technology Roadmap Program: Improved Surface Quality of Exposed Automotive Sheet Steels

    Energy Technology Data Exchange (ETDEWEB)

    John G. Speer; David K. Matlock; Noel Meyers; Young-Min Choi

    2002-10-10

    Surface quality of sheet steels is an important economic and technical issue for applications such as critical automotive surfaces. This project was therefore initiated to develop a more quantitative methodology for measuring surface imperfections, and to assess their response to forming and painting, particularly with respect to their visibility or invisibility after painting. The objectives were met, and included evaluation of a variety of imperfections present on commercial sheet surfaces or simulated using methods developed in the laboratory. The results are expected to have significant implications with respect to the methodology for assessing surface imperfections, development of quantitative criteria for surface inspection, and understanding and improving key painting process characteristics that influence the perceived quality of sheet steel surfaces.

  14. Reducing the Variability of HSLA Sheet Steels (TRP 9807)

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Anthony J. DeArdo

    2004-03-12

    The sensitivity of the yield strength of a 70 ksi HSLA steel to changes in processing variables was investigated using a laboratory hot-rolling mill. Along with a detailed examination of the hot-rolled microstructures, auxiliary experiments were conducted to determine how the decomposition of the austenite phase and the occurrence of ultra-fine precipitate formation could account for the yield strength variability. A set of guidelines was recommended for the reduction of the yield strength variability.

  15. Reduction of cross section area at fracture in tensile test: measurement and applications for flat sheet steels

    Science.gov (United States)

    Larour, P.; Freudenthaler, J.; Weissböck, T.

    2017-09-01

    This contribution deals with the use of maximum thinning and reduction of sample cross section area at fracture after tensile testing and applications for industrial flat sheet steels. Although included in all usual tensile testing standards, this mechanical property (“Z-value”) has long been neglected for flat sheet materials. It happens however to include some most valuable information on local ductility at fracture of sheet steels. This is increasingly needed for a more suitable description and ranking of newly developed advanced high strength sheet steels with regard to local ductility (stretch-flangeability, bendability, crash-ability) versus global ductility (deep-drawability). It is shown in this investigation that the ISO16630 punched and milled hole expansion ratio correlates linearly with the relative thickness reduction at fracture. A classification of cold rolled AHSS-UHSS sheet steels is attempted by plotting the relative thickness & area reduction at fracture vs. uniform and fracture elongation.

  16. Analysis of hot forming of a sheet metal component made of advanced high strength steel

    Science.gov (United States)

    Demirkaya, Sinem; Darendeliler, Haluk; Gökler, Mustafa İlhan; Ayhaner, Murat

    2013-05-01

    To provide reduction in weight while maintaining crashworthiness and to decrease the fuel consumption of vehicles, thinner components made of Advanced High Strength Steels (AHSS) are being increasingly used in automotive industry. However, AHSS cannot be formed easily at the room temperature (i.e. cold forming). The alternative process involves heating, hot forming and subsequent quenching. A-pillar upper reinforcement of a vehicle is currently being produced by cold forming of DP600 steel sheet with a thickness of 1.8 mm. In this study, the possible decrease in the thickness of this particular part by using 22MnB5 as appropriate AHSS material and applying this alternative process has been studied. The proposed process involves deep drawing, trimming, heating, sizing, cooling and piercing operations. Both the current production process and the proposed process are analyzed by the finite element method. The die geometry, blank holding forces and the design of the cooling channels for the cooling process are determined numerically. It is shown that the particular part made of 22MnB5 steel sheet with a thickness of 1.2 mm can be successfully produced by applying the proposed process sequence and can be used without sacrificing the crashworthiness. With the use of the 22MnB5 steel with a thickness of 1.2 mm instead of DP600 sheet metal with a thickness of 1.8 mm, the weight is reduced by approximately 33%.

  17. Microstructural investigations of the trimmed edge of DP980 steel sheets

    Science.gov (United States)

    Bhattacharya, S.; Green, D. E.; Sohmshetty, R.; Alpas, A. T.

    2017-10-01

    In order to reduce vehicle weight while maintaining crashworthiness, advanced high strength steels (AHSSs), such as DP980, are extensively used for manufacturing automotive body components. During trimming operations, the high tensile strength of DP980 sheets tends to cause damage of the trim edge of D2 die inserts, which result in deterioration of the edge quality. The objective of this work is to study the damage microstructures at the trimmed edge of DP980 steel sheets as a function of the number of trimming cycles. A mechanical press equipped with AISI D2 tool steel inserts was used to continuously trim 1.4 mm thick sheets of DP980 at a rate of 30 strokes/min. Cross-sectional SEM images of the trimmed edges revealed that the sheared edge quality of the DP980 sheets decreased, indicated by an increase in the burr width, with an increase in the number of trims from 40,000 to 70,000. Plastic strains were estimated using the displacements of the martensite plates within plastic flow fields of ferrite. Site-specific cross-sectional TEM samples, excised from the trimmed edge using the in-situ `lift-out' technique by focused ion-beam (FIB)-milling, revealed cracking at the ferrite/martensite interfaces after 70,000 cycles indicating an increase in the depth of deformation zone possibly due to trimming with a chipped and blunted die edge.

  18. Properties of hot-rolled sheets from ferritic steel with increased strength

    Science.gov (United States)

    Perlovich, Yu.; Isaenkova, M.; Dobrokhotov, P.; Stolbov, S.; Bannykh, O.; Bannykh, I.; Antsyferova, M.

    2017-10-01

    Sheets from ferritic steel 3 mm thick with increased strength after thermal hardening were studied by use of various X-ray methods and mechanical testing. Rolling of steel was carried out at 1100°C with rather great reductions per pass, so that plastic deformation of metal spread by the significant distance from the surface. The texture of sheet proved to have two sharply different layers: the inner layer of ˜40% thick with the usual rolling texture of BCC metals and the external layer with the rolling texture of FCC metals. At that, within the intermediate layer the texture is weakened. Texture formation within the external layer is conditioned by the process of dynamical deformation ageing: interstitial impurities from atmosphere block dislocations, prevent from their slip and at increased temperatures promote their collective climb. As a result, the direction of lattice rotation as well as the final rolling texture change. Due to texture layering, by impact testing of the sheet the plane of crack propagation must be changed when this crack reaches the inner layer, and then an additional energy for its further movement is required. Thermal hardening of the sheet retains the type of rolling texture, though results in some its scattering, but at the same time the breaking point of steel grows twice owing to formation of intermetallic particles.

  19. A new specimen for out-of-plane shear strength of advanced high strength steel sheets

    Science.gov (United States)

    Gu, B.; He, J.; Li, S. H.; Zhao, Y. X.; Li, Y. F.; Zeng, D.; Xia, Z. C.; Lin, Z. Q.

    2017-09-01

    Compared with the conventional steels, “shear fracture” is one of the main issues for advanced high strength steels (AHSS). Due to rolling, anisotropy is an intrinsic property for sheet metals. Not only the plastic responses of sheet metals but also the fracture strengths are orientation dependent. In the small radius forming process, for example, the stretch-bending deformation of sheet metals under small radius condition, the normal stress cannot be neglected. Three-dimensional loading condition constructs complex shear stress states of sheet metals especially the out-of-plane shear stress. The out-of-plane performance must be considered in order to better understand the “shear fracture” phenomenon of AHSS. Compared to in-plane shear test, the out-of-plane shear test is more difficult to carry out due to the severe restriction of the dimensions in the thickness direction. In this paper, a new specimen is presented for out-of-plane shear test. Failure of the specimen occurs in shear between two centrally located notches machined halfway through its thickness from opposing sides. Meanwhile, the finite element (FE) model and possible failure modes of this specimen are investigated in detail. At last, brief experimental results between out-of-plane shear fracture strength and the in-plane shear fracture strength are compared for DP980 sheets.

  20. The measurement of magnetic properties of electrical sheet steel - survey on methods and situation of standards

    CERN Document Server

    Sievert, J

    2000-01-01

    A brief review of the different requirements for magnetic measurement techniques for material research, modelling of material properties and grading of the electrical sheet steel for trade purposes is presented. In relation to the main application of laminated electrical steel, this paper deals with AC measurement techniques. Two standard methods, Epstein frame and Single Sheet Tester (SST), producing different results, are used in parallel. This dilemma was analysed in detail. The study leads to a possible solution of the problem, i.e. the possibility of converting the results of one of the two methods into the results of the other in order to satisfy the users of the Epstein method and, at the same time, to improve the acceptance of the more economical SST method.

  1. 76 FR 58536 - Tin- and Chromium-Coated Steel Sheet From Japan; Notice of Commission Determination To Conduct a...

    Science.gov (United States)

    2011-09-21

    ... on tin- and chromium-coated steel sheet from Japan would be likely to lead to continuation or.... Persons with mobility impairments who will need special assistance in gaining access to the Commission...

  2. Fact Sheet - Final Air Toxics Rule for Steel Pickling and HCI Process Facilities and Hydrochloric Acid Regeneration Plants

    Science.gov (United States)

    Fact Sheet summarizing the main points of the national emssions standard for hazaradous air pollutants (NESHAP) for Steel Pickling— HCl Process Facilities and Hydrochloric Acid Regeneration Plants as promulgated on June 22, 1999.

  3. Characterizing Grain-Oriented Silicon Steel Sheet Using Automated High-Resolution Laue X-ray Diffraction

    Science.gov (United States)

    Lynch, Peter; Barnett, Matthew; Stevenson, Andrew; Hutchinson, Bevis

    2017-11-01

    Controlling texture in grain-oriented (GO) silicon steel sheet is critical for optimization of its magnetization performance. A new automated laboratory system, based on X-ray Laue diffraction, is introduced as a rapid method for large scale grain orientation mapping and texture measurement in these materials. Wide area grain orientation maps are demonstrated for both macroetched and coated GO steel sheets. The large secondary grains contain uniform lattice rotations, the origins of which are discussed.

  4. Detection of Steel Fatigue Cracks with Strain Sensing Sheets Based on Large Area Electronics

    Directory of Open Access Journals (Sweden)

    Yao Yao

    2015-04-01

    Full Text Available Reliable early-stage damage detection requires continuous monitoring over large areas of structure, and with sensors of high spatial resolution. Technologies based on Large Area Electronics (LAE can enable direct sensing and can be scaled to the level required for Structural Health Monitoring (SHM of civil structures and infrastructure. Sensing sheets based on LAE contain dense arrangements of thin-film strain sensors, associated electronics and various control circuits deposited and integrated on a flexible polyimide substrate that can cover large areas of structures. This paper presents the development stage of a prototype strain sensing sheet based on LAE for crack detection and localization. Two types of sensing-sheet arrangements with size 6 × 6 inch (152 × 152 mm were designed and manufactured, one with a very dense arrangement of sensors and the other with a less dense arrangement of sensors. The sensing sheets were bonded to steel plates, which had a notch on the boundary, so the fatigue cracks could be generated under cyclic loading. The sensors within the sensing sheet that were close to the notch tip successfully detected the initialization of fatigue crack and localized the damage on the plate. The sensors that were away from the crack successfully detected the propagation of fatigue cracks based on the time history of the measured strain. The results of the tests have validated the general principles of the proposed sensing sheets for crack detection and identified advantages and challenges of the two tested designs.

  5. In Search of the Attributes Responsible for Sliver Formation in Cold Rolled Steel Sheets

    Science.gov (United States)

    Mohanty, Itishree; Das, Prasun; Bhattacharjee, Debashish; Datta, Shubhabrata

    2017-04-01

    Surface quality is one of the most important characteristics of cold rolled (CR) steel sheets for its application in consumer goods industries. The actual cause of sliver formation is very difficult to determine, as it is revealed only after the final cold rolling of the steel. A thorough investigation on searching the root cause of sliver formation in CR steel is done here using several statistical tools towards mining the industrial data for extraction of knowledge. As the complex interactions between the variables make it difficult to identify the cause, it is seen that findings from different techniques differed to a certain extent. Still it is revealed that 21 variables could be short listed as major contributor for sliver formation, but those are found to be from all the areas of the processing. This leads to the conclusion that no particular process variable or particular processing could be held responsible for sliver formation.

  6. The Effect of Grinding and Polishing Procedure of Tool Steels in Sheet Metal Forming

    DEFF Research Database (Denmark)

    Lindvall, F.; Bergström, J.; Krakhmalev, P.

    2010-01-01

    The surface finish of tools in sheet metal forming has a large influence on the performance of the forming tool. Galling, concern of wear in sheet metal forming, is a severe form of adhesive wear where sheet material is transferred on to the tool surface. By polishing the tools to a fine surface...... finish, material pick-up has traditionally been reduced, but some surface preparations withstand adhesive wear better. To investigate the effect on galling performance of different surface preparations lubricated tests have been performed using a strip reduction rig. Two different tool materials, Vancron...... 40 and Vanadis 6 and up to ten different grinding and polishing treatments were tested against AISI 316 stainless steel. The tests showed that an optimum surface preparation might be found at the transition between abrasive and adhesive wear....

  7. Failure Investigation for QP Steel Sheets under uniaxial and Equal-Biaxial Tension Conditions

    Science.gov (United States)

    Zou, Danqing; Li, Shuhui; He, Ji; Cui, Ronggao

    2016-08-01

    The Quenching and Partitioning (QP) steel sheet is new generation material to induce phase transformation for plasticity in forming vehicle parts. The phase transformation is strongly stress state dependent behavior in experiments, which should affect the failure timing and limit strain in forming processes. In this paper, Nakajima test with QP980 and DP1000 steel sheets under equal-biaxial loading condition is performed for failure behavior. X-ray diffraction (XRD) is adopted to obtain the volume fraction of retained austenite (fA). Digital Image Correlation (DIC) is used to record the surface strain field and its evolution during equal-biaxial tension deformation. The same level Dual Phase (DP) steel is also employed for the purpose of comparison. The results show that phase transformation in QP steel gives small impact on failure strain under equal biaxial tension condition which is contradicted with our understanding. It suggests that failure behavior under uniaxial tension of QP980 is strongly phase transformation dependent. But it shows almost independent under equal biaxial tension condition.

  8. 75 FR 17690 - Stainless Steel Sheet and Strip in Coils from Mexico; Extension of Time Limit for Preliminary...

    Science.gov (United States)

    2010-04-07

    ... International Trade Administration Stainless Steel Sheet and Strip in Coils from Mexico; Extension of Time Limit... is not practicable to complete the preliminary results of this review within the original time frame... received a timely request from both Mexinox and Allegheny Ludlum Corporation, AK Steel Corporation, and...

  9. Development of a test method for determining the cracking susceptibility of resistance spot welded high strength steel sheets

    OpenAIRE

    Rethmeier, Michael; Suwala, Hubert

    2014-01-01

    In this study a test method for determining the cracking susceptibility of resistance spot welded high strength steel sheets was investigated. The development of a suitable test procedure is based on the External-Loaded Hot Crack Test (PVC-Test). The test modification for resistance spot welding contains a constant tensile force load. The test method for determining the cracking susceptibility was experimentally verified for a high strength steel, a transformation induced plasticity steel (TR...

  10. Effects of Microalloying on Stretch-flangeability of Ultrahigh-strength TRIP-aided Martensitic Steel Sheets

    OpenAIRE

    Duc, Van Pham; Kobayashi, Junya; Sugimoto, Koh-Ichi

    2014-01-01

    The effects of Cr, Mo, and Ni addition on the microstructure and stretch-flangeability of a 0.2%C-1.5%Si-1.5%Mn-0.05%Nb (mass%) transformation-induced plasticity (TRIP)-aided martensitic steel sheet produced by an isothermal transformation process at a temperature below martensite transformation-finish temperatures were investigated in order to develop third-generation steel sheet for automobiles requiring high hardenability. When 0.5% or 1.0% Cr was added to the base steel, a tensile strengt...

  11. Parametric study on numerical simulation of the electromagnetic forming of DP780 steel workpiece with aluminium driver sheet

    Science.gov (United States)

    Park, Hyeonil; Lee, Jinwoo; Kim, Se-Jong; Lee, Youngseon; Kim, Daeyong

    2016-08-01

    The purpose of this study is to investigate the influences of numerical parameters on the electromagnetic forming (EMF) simulation. The 3-dimensional coupled electromagnetic- mechanical simulations were conducted to predict the deformation behavior of the advanced high strength steel (AHSS) sheet receiving support in EMF with aluminum driver sheet. Dual phase (DP) 780 steel workpiece was formed into a hemi elliptical protrusion shape with aluminum alloy AA1050 driver sheet using a flat spiral coil actuator and open cavity die. The deformed shape of the DP780 workpiece and the computation time with respect to element size, N cycle number and time step of electromagnetic (EM) solver were analysed.

  12. Dissimilar Arc Welding of Advanced High-Strength Car-Body Steel Sheets

    Science.gov (United States)

    Russo Spena, P.; D'Aiuto, F.; Matteis, P.; Scavino, G.

    2014-11-01

    A widespread usage of new advanced TWIP steel grades for the fabrication of car-body parts is conditional on the employment of appropriate welding methods, especially if dissimilar welding must be performed with other automotive steel grades. Therefore, the microstructural features and the mechanical response of dissimilar butt weld seams of TWIP and 22MnB5 steel sheets after metal-active-gas arc welding are examined. The microstructural and mechanical characterization of the welded joints was carried out by optical metallography, microhardness and tensile testing, and fractographic examination. The heat-affected zone on the TWIP side was fully austenitic and the only detectable effect was grain coarsening, while on the 22MnB5 side it exhibited newly formed martensite and tempered martensite. The welded tensile specimens exhibited a much larger deformation on the TWIP steel side than on the 22MnB5. The fracture generally occurred at the interface between the fusion zone and the heat-affected zones, with the fractures surfaces being predominantly ductile. The ultimate tensile strength of the butt joints was about 25% lower than that of the TWIP steel.

  13. Optimization of CO2 laser cutting parameters on Austenitic type Stainless steel sheet

    Science.gov (United States)

    Parthiban, A.; Sathish, S.; Chandrasekaran, M.; Ravikumar, R.

    2017-03-01

    Thin AISI 316L stainless steel sheet widely used in sheet metal processing industries for specific applications. CO2 laser cutting is one of the most popular sheet metal cutting processes for cutting of sheets in different profile. In present work various cutting parameters such as laser power (2000 watts-4000 watts), cutting speed (3500mm/min - 5500 mm/min) and assist gas pressure (0.7 Mpa-0.9Mpa) for cutting of AISI 316L 2mm thickness stainless sheet. This experimentation was conducted based on Box-Behenken design. The aim of this work is to develop a mathematical model kerf width for straight and curved profile through response surface methodology. The developed mathematical models for straight and curved profile have been compared. The Quadratic models have the best agreement with experimental data, and also the shape of the profile a substantial role in achieving to minimize the kerf width. Finally the numerical optimization technique has been used to find out best optimum laser cutting parameter for both straight and curved profile cut.

  14. Corrosion Behavior of MIG Brazed and MIG Welded Joints of Automotive DP600-GI Steel Sheet

    Science.gov (United States)

    Basak, Sushovan; Das, Hrishikesh; Pal, Tapan Kumar; Shome, Mahadev

    2016-12-01

    Galvanized dual-phase steel sheets are extensively used by the auto industry for their corrosion resistance property. Welding by the metal inert gas (MIG) process causes degradation of the steel in the vicinity of the joint due to excessive zinc evaporation. In order to minimize Zn loss, the MIG brazing process has been tried out in lap joint configuration over a heat input range of 136-204 J mm-1. The amount of zinc loss, intermetallic formation and corrosion properties in the joint area has been evaluated for both MIG brazing and MIG welding. Corrosion rate of 21 mm year-1 has been reduced to 2 mm year-1 by adopting MIGB in place MIGW. Impedance study has shown that the corrosion mechanism in base metal, MIG brazed and MIG welded joints is dominated by charge transfer, diffusion and mixed mode control processes, respectively.

  15. A Sustainable Approach for Optimal Steel Sheet Pile Structure Assessment, Maintenance, and Rehabilitation

    Science.gov (United States)

    2011-09-30

    disasters, foundation failures, failures of dams and dikes, corrosion-related failures, and earthquake damag - es. • Leonards (1982) defined failures...developed under REMR focused on concrete and steel materials, along with geotechnical , hydraulic, electrical and mechanical, environmental, and coastal...construction activities (e.g., delay at work zone). Nonuser social costs such as environmental damage are not considered (Chan et al. 2008). State DOTs use

  16. Phase analysis of fume during arc weld brazing of steel sheets with protective coatings

    Directory of Open Access Journals (Sweden)

    J. Matusiak

    2016-04-01

    Full Text Available The article presents the results of research of the phase identification and of the quantitative phase analysis of fume generated during Cold Metal Transfer (CMT, ColdArc and Metal Inert Gas / Metal Active Gas (MIG / MAG weld brazing. Investigations were conducted for hot - dip coated steel sheets with zinc (Zn and zinc-iron (Zn - Fe alloy coatings. Arc shielding gases applied during the research-related tests were Ar + O2, Ar + CO2, Ar + H2 and Ar + CO2 + H2 gas mixtures. The analysis of the results covers the influence of the chemical composition of shielding gas on the chemical composition of welding fume.

  17. SPR Characteristics Curve and Distribution of Residual Stress in Self-Piercing Riveted Joints of Steel Sheets

    Directory of Open Access Journals (Sweden)

    Rezwanul Haque

    2017-01-01

    Full Text Available Neutron diffraction was used to describe the residual stress distributions in self-piercing riveted (SPR joints. The sheet material displayed a compressive residual stress near the joint, and the stress gradually became tensile in the sheet material far away from the joint. The stress in the rivet leg was lower in the thick joint of the softer steel sheet than in the thin joint of the harder steel sheet. This lower magnitude was attributed to the lower force gradient during the rivet flaring stage of the SPR process curve. This study shows how the residual stress results may be related to the physical occurrences that happened during joining, using the characteristics curve. The study also shows that neutron diffraction technique enabled a crack in the rivet tip to be detected which was not apparent from a cross-section.

  18. INVESTIGATION OF POTENTIALITIES TO SET AUTOMATICALLY AMPLITUDE VALUES OF MAGNETIC INDUCTION WHILE MEASURING MAGNETIC CHARACTERISTICS OF ELECTRICAL-SHEET STEEL

    Directory of Open Access Journals (Sweden)

    I. I. Branovitsky

    2005-01-01

    Full Text Available The problems relating to an automation of measurement of magnetic characteristics of electrical-sheet steel have been considered in the paper. The paper investigates efficiency of an application of some well-known iterative methods for setting the required amplitude value of a magnetic induction of the material to be tested. It is shown that the most efficient method providing a fast and stable convergence of an iterative process while testing either textured or isotropic electrical-sheet steel is a parabola method.

  19. Orientation Dependence of Cracking in Hot-Dip Zn-Al-Mg Alloy Coatings on a Sheet Steel

    Science.gov (United States)

    Park, Y. B.; Kim, I. G.; Kim, S. G.; Kim, W. T.; Kim, T. C.; Oh, M. S.; Kim, J. S.

    2017-03-01

    The present study was aimed at investigating a basic cause of cracking in hot-dip Zn-Al-Mg alloy coatings on an extra deep drawing quality sheet steel. The electron backscattering diffraction technique was employed to examine the crystallographic planes of the cracks generated before and after bending deformation of the coated steel sheets. It was clarified that the occurrence of cracking in the Zn-Al-Mg alloy coatings absolutely depends on the orientation of the primary Zn and eutectic Zn alloy phases. Finally, a cracking mechanism was proposed on the basis of the anisotropy of thermal expansion and the Young's modulus in the phases constituting the coatings.

  20. Corrosion of steel members strengthenened with carbon fiber reinforced polymer sheets

    Science.gov (United States)

    Bumadian, Ibrahim

    Due to many years of service at several cases of exposure at various environments there are many of steel bridges which are in need of rehabilitation. The infrastructure needs upgrading, repair or maintenance, and also strengthening, but by using an alternative as retrofits methods. The alternative retrofit method, which used fiber reinforced polymer (FRP) composite materials which their strength materials comes largely from the fiber such as carbon, glass, and aramid fiber. Of the most important materials used in the rehabilitation of infrastructure is a composite material newly developed in bonded externally carbon fiber and polymer (CFRP) sheets, which has achieved remarkable success in the rehabilitation and upgrading of structural members. This technique has many disadvantages one of them is galvanic corrosion. This study presents the effect of galvanic corrosion on the interfacial strength between carbon fiber reinforced polymer (CFRP) sheets and a steel substrate. A total of 35 double-lap joint specimens and 19 beams specimens are prepared and exposed to an aggressive service environment in conjunction with an electrical potential method accelerating corrosion damage. Six test categories are planned at a typical exposure interval of 12 hours, including five specimens per category for double-lap joint specimens. And six test categories are planned at a typical exposure interval of 12 hours, including three specimens per category for Beam section specimens. In addition one beam section specimen is control. The degree of corrosion is measured. Fourier transform infrared (FTIR) reflectance spectroscopy has been used to monitor and confirm the proposed corrosion mechanisms on the surface of CFRP. In this study we are using FTIR-spectroscopic measurement systems in the mid infrared (MIR) wavelength region (4000 - 400) cm-1 to monitor characteristic spectral features. Upon completion of corrosion processes, all specimens are monotonically loaded until failure

  1. Tailoring the mechanical properties of steel sheets using FeC films and diffusion annealing

    Energy Technology Data Exchange (ETDEWEB)

    Cantergiani, Elisa [Department of Mechanical Engineering, University of Ottawa, 161 Louis Pasteur, Ottawa, ON, Canada K1N 6N5 (Canada); Fillon, Amélie [Université de Rouen, Groupe de Physique des Matériaux, UMR CNRS 6634, BP-12, 76801, Saint Etienne du Rouvray Cedex (France); Lawrence, Ben [The University of British Columbia, Dept. of Materials Engineering, 309-6350 Stores Road, Vancouver, Canada V6T1Z4 (Canada); Sauvage, Xavier [Université de Rouen, Groupe de Physique des Matériaux, UMR CNRS 6634, BP-12, 76801, Saint Etienne du Rouvray Cedex (France); Perez, Michel [Université de Lyon, MATEIS-INSA-Lyon, UMR CNRS 5510, 69621 Villeurbanne (France); Scott, Colin P. [Canmet MATERIALS, Hamilton, ON, Canada L8P0A5 (Canada); Weck, Arnaud, E-mail: aweck@uottawa.ca [Department of Mechanical Engineering, University of Ottawa, 161 Louis Pasteur, Ottawa, ON, Canada K1N 6N5 (Canada); Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, Canada K1N 6N5 (Canada); Centre for Research in Photonics at the University of Ottawa, 800 King Edward Ave., Ottawa, ON, Canada K1N 6N5 (Canada)

    2016-03-07

    In this work amorphous FeC films were deposited on thin sheets of interstitial free steel using physical vapor deposition. Annealing treatments were then carried out to diffuse C from the coating into the substrate at temperatures lower than those traditionally used in carburizing treatments. The yield stress was shown to significantly increase with annealing temperature from ~120 MPa at 25 °C up to a maximum of 300 MPa at 630 °C without any significant loss of ductility. At 710 °C, a decrease in yield strength was related to the coarsening of carbides inside the IF steel (confirmed by atom probe tomography), and the associated reduction in the matrix solid solution carbon concentration (confirmed by thermoelectric power measurements). The through-thickness carbon diffusion profile was predicted using Fick's law and validated by Knoop hardness measurements. Yield strength predictions were accurate if the crystallization of the FeC film was taken into account as it controls the amount of carbon available to be diffused in the interstitial free steel substrate.

  2. Investigation on the cold rolling and structuring of cold sprayed copper-coated steel sheets

    Science.gov (United States)

    Bobzin, K.; Öte, M.; Wiesner, S.; Gerdt, L.; Senge, S.; Hirt, G.

    2017-03-01

    A current driving force of research is lightweight design. One of the approaches to reduce the weight of a component without causing an overall stiffness decrease is the use of multi-material components. One of the main challenges of this approach is the low bonding strength between different materials. Focusing on steel-aluminum multi-material components, thermally sprayed copper coatings can come into use as a bonding agent between steel sheets and high pressure die cast aluminum to improve the bonding strength. This paper presents a combination of cold gas spraying of copper coatings and their subsequent structuring by rolling as surface pretreatment method of the steel inserts. Therefore, flat rolling experiments are performed with samples in “as sprayed” and heat treated conditions to determine the influence of the rolling process on the bond strength and the formability of the coating. Furthermore, the influence of the rolling on the roughness and the hardness of the coating was examined. In the next step, the coated surface was structured, to create a surface topology suited for a form closure connection in a subsequent high-pressure die casting process. No cracks were observed after the cold rolling process with a thickness reduction of up to ε = 14 % for heat treated samples. Structuring of heat treated samples could be realized without delamination and cracking.

  3. Microstructural and Mechanical Study of Press Hardening of Thick Boron Steel Sheet

    Science.gov (United States)

    Pujante, J.; Garcia-Llamas, E.; Golling, S.; Casellas, D.

    2017-09-01

    Press hardening has become a staple in the production of automotive safety components, due to the combination of high mechanical properties and form complexity it offers. However, the use of press hardened components has not spread to the truck industry despite the advantages it confers, namely affordable weight reduction without the use of exotic materials, would be extremely attractive for this sector. The main reason for this is that application of press hardened components in trucks implies adapting the process to the manufacture of thick sheet metal. This introduces an additional layer of complexity, mainly due to the thermal gradients inside the material resulting in though-thickness differences in austenitization and cooling, potentially resulting in complex microstructure and gradient of mechanical properties. This work presents a preliminary study on the press hardening of thick boron steel sheet. First of all, the evolution of the sheet metal during austenitization is studied by means of dilatometry tests and by analysing the effect of furnace dwell time on grain size. Afterwards, material cooled using different cooling strategies, and therefore different effective cooling rates, is studied in terms of microstructure and mechanical properties. Initial results from finite element simulation are compared to experimental results, focusing on the phase composition in through thickness direction. Results show that industrial-equivalent cooling conditions do not lead to gradient microstructures, even in extreme scenarios involving asymmetrical cooling.

  4. Numerical and Experimental Investigation into Hot Forming of Ultra High Strength Steel Sheet

    Science.gov (United States)

    Liu, Hongsheng; Liu, Wei; Bao, Jun; Xing, Zhongwen; Song, Baoyu; Lei, Chengxi

    2011-02-01

    Hot forming of ultra high strength steel (UHSS) sheet metal grade 22MnB5 boron for channel components using water cooling is studied on a laboratory scale. After hot forming, the different microstructures such as martensite, bainite, and pearlite in formed component are produced, which are closely related with mechanical properties of formed component. The effect of forming start temperature and the contact state between blank and die on the microstructure evolution is investigated. In addition, the effect of processing parameters, such as forming start temperature and blank holder force (BHF), on the final quality of component, i.e., springback, that happens after hot forming of UHSS is investigated. It can be concluded that the forming start temperature has a significant effect on the final mechanical properties of formed components. The effect of forming start temperature on springback is examined in detail under a wide range of operating conditions. The higher the BHF and the forming start temperature, the lower is the springback after hot forming. Furthermore, thermo-mechanically coupled finite element analysis model encompassing heating of sheet blank, forming and quenching are developed for hot forming process. The stress distributions on sheet blank under different conditions during hot forming are compared to gain a fundamental understanding of the mechanism of springback. Comparisons show that numerical simulation results have good agreement with experimental results.

  5. 76 FR 77013 - Tin- and Chromium-Coated Steel Sheet From Japan; Scheduling of a Full Five-Year Review Concerning...

    Science.gov (United States)

    2011-12-09

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Tin- and Chromium-Coated Steel Sheet From Japan; Scheduling of a Full Five-Year Review Concerning... of the antidumping duty order on tin- and chromium-coated steel sheet from Japan would be likely to...

  6. Microstructural Developments Leading to New Advanced High Strength Sheet Steels: A Historical Assessment of Critical Metallographic Observations

    Energy Technology Data Exchange (ETDEWEB)

    Matlock, David K [CSM/ASPPRC; Thomas, Larrin S [CSM/ASPPRC; Taylor, Mark D [CSM/ASPPRC; De Moor, Emmanuel [CSM/ASPPRC; Speer, John G [CSM/ASPPRC

    2015-08-03

    In the past 30+ years significant advancements have been made in the development of higher strength sheet steels with improved combinations of strength and ductility that have enabled important product improvements leading to safer, lighter weight, and more fuel efficient automobiles and in other applications. Properties of the primarily low carbon, low alloy steels are derived through careful control of time-temperature processing histories designed to produce multiphase ferritic based microstructures that include martensite and other constituents including retained austenite. The basis for these developments stems from the early work on dual-phase steels which was the subject of much interest. In response to industry needs, dual-phase steels have evolved as a unique class of advanced high strength sheet steels (AHSS) in which the thermal and mechanical processing histories have been specifically designed to produce constituent combinations for the purpose of simultaneously controlling strength and deformation behavior, i.e. stress-strain curve shapes. Improvements continue as enhanced dual-phase steels have recently been produced with finer microstructures, higher strengths, and better overall formability. Today, dual phase steels are the primary AHSS products used in vehicle manufacture, and several companies have indicated that the steels will remain as important design materials well into the future. In this presentation, fundamental results from the early work on dual-phase steels will be reviewed and assessed in light of recent steel developments. Specific contributions from industry/university cooperative research leading to product improvements will be highlighted. The historical perspective provided in the evolution of dual-phase steels represents a case-study that provides important framework and lessons to be incorporated in next generation AHSS products.

  7. An experimental study on fracture toughness of resistance spot welded galvanized and ungalvanized DP 450 steel sheets used in automotive body

    Directory of Open Access Journals (Sweden)

    Sevim, Ibrahim

    2016-09-01

    Full Text Available The purpose of this study is to determine fracture toughness of Resistance Spot Welded (RSW Dual Phase (DP steels. RSW of galvanized and ungalvanized DP 450 steel sheets was carried out on spot welding machine. Fracture toughness of RSW joints of galvanized and ungalvanized DP 450 steel sheets was calculated from tensile-shear tests. New empirical equations were developed using Least Squares Method (LSM between energy release rate, fracture toughness and critical crack size depending on the relationship between hardness and fracture toughness values. Results indicated that fracture toughness of joints welded by using RSW increased exponentially while the hardness decreased. In addition, fracture toughness and energy release rate of RSW galvanized DP 450 steel sheets were lower compared to RSW ungalvanized DP 450 steel sheets which had approximately the same hardness.El objetivo de este estudio es determinar la tenacidad de fractura de los aceros dual (DP soldados por puntos de resistencia (RSW. En la máquina de soldadura por puntos se realizó la soldadura de láminas de acero DP 450 galvanizado y sin galvanizar. A partir de los ensayos de tracción-cizallamiento, se calculó la tenacidad a la fractura de las uniones del acero DP 450 galvanizado y sin galvanizar. Aplicando el método de mínimos cuadrados (LSM se desarrollaron nuevas ecuaciones empíricas entre el porcentaje de energía liberada, la tenacidad de fractura y el tamaño de grieta crítica en función de la relación entre los valores de tenacidad de fractura y de dureza. Los resultados indicaron que la tenacidad de fractura de las uniones soldadas por RSW aumentó exponencialmente, mientras que la dureza disminuyó. Además, el porcentaje de energía liberada de las láminas de acero DP 450 galvanizadas y soldadas fueron menores que en el caso de las láminas sin galvanizar a valores iguales de dureza.

  8. Toward the production of 50 000 tonnes of low-carbon steel sheet for the LHC superconducting dipole and quadrupole magnets

    CERN Document Server

    Babic, S; Beckers, F; Brixhe, F; Peiro, G; Verbeeck, T

    2002-01-01

    A total of 50 000 tonnes of low-carbon steel sheet has been ordered for the LHC main magnets. After three years of production, about 10 000 tonnes of steel sheet have been produced by Cockerill-Sambre Groupe Usinor. This paper gives a summary of the manufacturing process and improvements implemented as well as an overview of the difficulties encountered during this production. Preliminary statistics obtained for the mechanical and magnetic steel properties are presented. (6 refs).

  9. Towards the production of 50'000 tonnes of low-carbon steel sheet for the LHC superconducting dipole and quadrupole magnets

    CERN Document Server

    Babic, S; Brixhe, F; Comel, S; Peiro, G; Verbeeck, T

    2002-01-01

    A total of 50'000 tonnes of low-carbon steel sheet has been ordered for the LHC main magnets. After three years of production, about 10'000 tonnes of steel sheet have been produced by Cockerill-Sambre Groupe Usinor. This paper gives a summary of the manufacturing process and improvements implemented as well as an overview of the difficulties encountered during this production. Preliminary statistics obtained for the mechanical and magnetic steel properties are presented.

  10. Statistical modeling of laser welding of DP/TRIP steel sheets

    Science.gov (United States)

    Reisgen, U.; Schleser, M.; Mokrov, O.; Ahmed, E.

    2012-02-01

    In this research work, a statistical analysis of the CO 2 laser beam welding of dual phase (DP600)/transformation induced plasticity (TRIP700) steel sheets was done using response surface methodology. The analysis considered the effect of laser power (2-2.2 kW), welding speed (40-50 mm/s) and focus position (-1 to 0 mm) on the heat input, the weld bead geometry, uniaxial tensile strength, formability limited dome height and welding operation cost. The experimental design was based on Box-Behnken design using linear and quadratic polynomial equations for predicting the mathematical models. The results indicate that the proposed models predict the responses adequately within the limits of welding parameters being used and the welding speed is the most significant parameter during the welding process.

  11. Sealable joint steel sheet piling for groundwater control and remediation: Case histories

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, D. [Univ. of Waterloo (Canada); Jowett, R. [Waterloo Barrier Inc., Rockwood, Ontario (Canada); Gamble, M. [C3 Environmental, Breslau, Ontario (Canada)

    1997-12-31

    The Waterloo Barrier{trademark} steel sheet piling (patents pending) incorporates a cavity at each interlocking joint that is flushed clean and injected with sealant after the piles have been driven into the ground to form a vertical cutoff wall. The installation and sealing procedures allow for a high degree of quality assurance and control. Bulk wall hydraulic conductivities of 10{sup -8} to 10{sup -10} cm/sec have been demonstrated at field installations. Recent case histories are presented in which Waterloo Barrier{trademark} cutoff walls are used to prevent off-site migration of contaminated groundwater or soil gases to adjacent property and waterways. Full enclosures to isolate DNAPL source zones or portions of contaminated aquifers for pilot-scale remediation testing will also be described. Monitoring data will be used to demonstrate the effectiveness of the Waterloo Barrier{trademark} in these applications.

  12. Use of a geomembrane steel sheet pile verticle barrier to curtail organic seepage

    Energy Technology Data Exchange (ETDEWEB)

    Guglielmetti, J.L.; Butler, P.B. [DuPont Environmental Remediation Services, Wilmington, DE (United States)

    1997-12-31

    At a Superfund site in Delaware, contaminated groundwater, seeping out of a riverbank, produced a visible sheen on the river. As part of an emergency response action, a geomembrane steel sheet pile vertical barrier system was installed to contain the sheen and contaminated soil and sediments. The response action presented an engineering challenge due to the close proximity manufacturing facilities, steep riverbank slopes, tidal fluctuations, high velocity river flow, and underground and overhead interferences. A unique vertical containment barrier was developed to stabilize the riverbank slope, curtail sheens on the river, and prevent groundwater mounding behind the vertical barrier. In addition, the cost-effective vertical barrier enables natural chemical and biological processes to contain the organic seepage without requiring a groundwater extraction system.

  13. Temperature effects on the magnetic properties of silicon-steel sheets using standardized toroidal frame.

    Science.gov (United States)

    Wu, Cheng-Ju; Lin, Shih-Yu; Chou, Shang-Chin; Tsai, Chia-Yun; Yen, Jia-Yush

    2014-01-01

    This study designed a detachable and standardized toroidal test frame to measure the electromagnetic characteristic of toroidal laminated silicon steel specimens. The purpose of the design was to provide the measurements with standardized and controlled environment. The device also can withstand high temperatures (25-300°C) for short time period to allow high temperature tests. The accompanying driving circuit facilitates testing for high frequency (50-5,000 Hz) and high magnetic flux (0.2-1.8 T) conditions and produces both sinusoidal and nonsinusoidal test waveforms. The thickness of the stacked laminated silicon-steel sheets must be 30~31 mm, with an internal diameter of 72 mm and an outer diameter of 90 mm. With the standardized setup, it is possible to carry out tests for toroidal specimen in high temperature and high flux operation. The test results show that there is a tendency of increased iron loss under high temperature operation. The test results with various driving waveforms also provide references to the required consideration in engineering designs.

  14. Influence of the mechanical fatigue progress on the magnetic properties of electrical steel sheets

    Directory of Open Access Journals (Sweden)

    Karthaus Jan

    2017-06-01

    Full Text Available The purpose of this paper is to study the variation of the magnetic properties of non-oriented electrical steel sheets with the fatigue state during cyclic mechanical loading. The obtained results are central to the design of variable drives such as traction drives in electric vehicles in which varying mechanical loads, e.g. in the rotor core (centrifugal forces, alter the magnetic properties. Specimens of non-oriented electrical steel are subject to a cyclically varying mechanical tensile stress with different stress amplitudes and number of cycles. The specimens are characterised magnetically at different fatigue states for different magnetic flux densities and magnetising frequencies. The measurements show a variation in magnetic properties depending on the number of cycles and stress magnitude which can be explained by changes in the material structure due to a beginning mechanical fatigue process. The studied effect is critical for the estimation of the impact of mechanical material fatigue on the operational behaviour of electrical machines. Particularly in electrical machines with a higher speed where the rotor is stressed by high centrifugal forces, material fatigue occurs and can lead to deterioration of the rotor’s stack lamination.

  15. INVESTIGATING SPOT WELD GROWTH ON 304 AUSTENITIC STAINLESS STEEL (2 mm SHEETS

    Directory of Open Access Journals (Sweden)

    NACHIMANI CHARDE

    2013-02-01

    Full Text Available Resistance spot welding (RSW has revolutionized automotive industries since early 1970s for its mechanical assemblies. To date one mechanical assembly out five is welded using spot welding technology in various industries and stainless steel became very popular among common materials. As such this research paper analyses the spot weld growth on 304 austenitic stainless steels with 2mm sample sheets. The growth of a spot weld is primarily determined by its parameters such as current, weld time, electrode tip and force. However other factors such as electrode deformations, corrosions, dissimilar materials and material properties are also affect the weld growth. This paper is intended to analyze only the effects of nuggets growth due to the current and weld time increment with constant force and unchanged electrode tips. A JPC 75kVA spot welder was used to accomplish it and the welded samples were undergone tensile test, hardness test and metallurgical test to characterize the formation of weld nuggets.

  16. Mechanical Properties Involved in the Micro-forming of Ultra-thin Stainless Steel Sheets

    Science.gov (United States)

    Pham, Cong-Hanh; Thuillier, Sandrine; Manach, Pierre-Yves

    2015-08-01

    The objective of this paper is to characterize the mechanical behavior of an ultra-thin stainless steel, of 0.15-mm thickness, that is commonly used in the manufacturing of miniature connectors. The main focus is the relationship between some microstructural features, like grain size and surface roughness, and the macroscopic mechanical behavior investigated in uniaxial tension and simple shear. In tension, adaptations to the very small sheet thickness, in order to hold the specimen under the grips, are presented. Yield stress, initial elastic modulus, and evolution of the loading-unloading slope with plastic deformation were evaluated. Moreover, the kinematic contribution to the hardening was characterized by monotonic and cyclic simple shear test and reproduced by a mixed hardening law implemented in Abaqus finite element code. Then, the evolution of surface roughness with plastic strain, both in tension and simple shear, was analyzed. It was shown that in the case of an ultra-thin sheet, the stress levels, calculated either from an average thickness or when considering the effect of the surface roughness, exhibit a significant difference. Finally, the influence of surface roughness on the fracture of a tensile specimen was also investigated.

  17. An experimental study on fracture toughness of resistance spot welded galvanized and ungalvanized DP 450 steel sheets used in automotive body

    Energy Technology Data Exchange (ETDEWEB)

    Sevim, I.

    2016-07-01

    The purpose of this study is to determine fracture toughness of Resistance Spot Welded (RSW) Dual Phase (DP) steels. RSW of galvanized and ungalvanized DP 450 steel sheets was carried out on spot welding machine. Fracture toughness of RSW joints of galvanized and ungalvanized DP 450 steel sheets was calculated from tensile-shear tests. New empirical equations were developed using Least Squares Method (LSM) between energy release rate, fracture toughness and critical crack size depending on the relationship between hardness and fracture toughness values. Results indicated that fracture toughness of joints welded by using RSW increased exponentially while the hardness decreased. In addition, fracture toughness and energy release rate of RSW galvanized DP 450 steel sheets were lower compared to RSW ungalvanized DP 450 steel sheets which had approximately the same hardness. (Author)

  18. TECHNOLOGY OF REVERSE-BLAST CORROSION CLEANING OF STEEL SHEETS PRIOR TO LASER CUTTING

    Directory of Open Access Journals (Sweden)

    A. N. Zguk

    2017-01-01

    Full Text Available Quality of surface cleaning against corrosion influences on efficiency in realization of a number of technological processes. While using bentonite clays in power fluid reverse-blast cleaning ensures formation of anticorrosion protective coating with light absorbing properties on the cleaned surface and prevents formation of the repeated corrosion. The paper presents results of the investigations pertaining to influence of reverse-blast cleaning parameters of steel sheets on quality of the cleaned surface prior to laser cutting. Processing conditions, applied compositions of power fluid and also properties of the protective film coatings on the cleaned surface have been given in the paper. The paper considers topography, morphology and chemical composition of the given coating while applying complex metal micrographic, X-ray diffraction and electronic and microscopic investigations. A complex of laser cutting (refer to gas lasers with output continuous capacity of 2.5/4.0 kW has been applied for experimental works to evaluate influence of the formed surface quality on efficiency of laser cutting process. Specimens having dimension 120×120 mm, made of steel Ст3пс, with thickness from 3 to 10 mm have been prepared for the experiments. An analysis has shown that the application of reverse-blast cleaning ensures higher speed in laser cutting by a mean of 10–20 %. The investigations have made it possible to determine optimum cleaning modes: distance from a nozzle to the surface to be cleaned, jet velocity, pressure. It has been revealed that after drying of the specimens processed by power fluid based on water with concentrations of bentonite clay and calcined soda a protective film coating with thickness of some 5–7 µm has been formed on the whole cleaned specimen surfaces. Chemical base of the coating has been formed by the elements which are included in the composition of bentonite clay being the basic component of the power fluid. 

  19. Comparative Analysis of Welded and Adhesive Joints Strength Made of Acid-Resistant Stainless Steel Sheets

    Directory of Open Access Journals (Sweden)

    Izabela Miturska

    2017-12-01

    Full Text Available The article presents the selected results of strength tests on the effectiveness of bonding high-alloy steel 1.4310. Sheet steel is one of the materials that are difficult to activate energy. Effective joining of it is difficult, requires selection of the appropriate bonding technology. The paper focuses on the comparative tests the shear strength of one-single lap welded and bonded joints. The welding process was performed 3 groups of samples TIG welding and argon, where the variable value of the welding process was current: 60A, 70A, 80A. The adhesion process was performed in 6 groups of samples which differed in the method of surface preparation and the type of the adhesive. Adhesive joints were made by using adhesive of epoxy resin and a hardener: Epidian 61/TFF at a mass ratio of 100:22 and Epidian 61/IDA at a mass ratio of 100:40. As a way of surface preparation applied 3 different, but simplified and environmentally friendly methods of surface preparation: degreasing with using cleaner Loctite 7061, abrasive machining with P320 and degreasing and grinding with abrasive T800 and degreasing were used. Make joints and curing the adhesive joints were carried out at ambient temperature. Analyzed the joints were tested destructive - which set out the shear strength, in accordance with DIN EN 1465 on the testing machine Zwick / Roell Z150. Based on the results of research it was found that better results were obtained for the maximum welded joints, but this result was similar to the maximum value of the strength of the adhesive bond.

  20. Modeling and FE Simulation of Quenchable High Strength Steels Sheet Metal Hot Forming Process

    Science.gov (United States)

    Liu, Hongsheng; Bao, Jun; Xing, Zhongwen; Zhang, Dejin; Song, Baoyu; Lei, Chengxi

    2011-08-01

    High strength steel (HSS) sheet metal hot forming process is investigated by means of numerical simulations. With regard to a reliable numerical process design, the knowledge of the thermal and thermo-mechanical properties is essential. In this article, tensile tests are performed to examine the flow stress of the material HSS 22MnB5 at different strains, strain rates, and temperatures. Constitutive model based on phenomenological approach is developed to describe the thermo-mechanical properties of the material 22MnB5 by fitting the experimental data. A 2D coupled thermo-mechanical finite element (FE) model is developed to simulate the HSS sheet metal hot forming process for U-channel part. The ABAQUS/explicit model is used conduct the hot forming stage simulations, and ABAQUS/implicit model is used for accurately predicting the springback which happens at the end of hot forming stage. Material modeling and FE numerical simulations are carried out to investigate the effect of the processing parameters on the hot forming process. The processing parameters have significant influence on the microstructure of U-channel part. The springback after hot forming stage is the main factor impairing the shape precision of hot-formed part. The mechanism of springback is advanced and verified through numerical simulations and tensile loading-unloading tests. Creep strain is found in the tensile loading-unloading test under isothermal condition and has a distinct effect on springback. According to the numerical and experimental results, it can be concluded that springback is mainly caused by different cooling rats and the nonhomogengeous shrink of material during hot forming process, the creep strain is the main factor influencing the amount of the springback.

  1. Temperature-dependent yield criterion for high strength steel sheets under warm-forming conditions

    Directory of Open Access Journals (Sweden)

    Cai Zhengyang

    2015-01-01

    Full Text Available In this paper, uniaxial and biaxial tensile tests with cruciform specimens were conducted to investigate the deformation behaviour of dual phase steel sheet with a tensile strength of 590 MPa (DP590 under evaluated warm-forming temperatures (20–190 ∘C. Detailed analyses were then carried out to obtain the corresponding experimental yield loci. For the purpose of describing the temperature-dependent yield behaviour of DP590 appropriately, the Yld2000–2d yield function with temperature-dependent exponent was proposed. The identification procedures of the introduced parameters were then proposed based on Levenberg-Marquardt optimization algorithm. Afterwards, the proposed model was implemented into ABAQUS as user subroutine VUMAT with NICE (Next Increment Corrects Error explicit integration scheme. The numerical simulations of biaxial tensile tests were then conducted to confirm the validity of the proposed model. It could be concluded that the flexibility and accuracy of the proposed model guarantee the applicability in warm-forming applications.

  2. Very high cycle fatigue strength and crack growth of thin steel sheets

    Directory of Open Access Journals (Sweden)

    Mohand Ouarabi

    2016-03-01

    Full Text Available For basic observations or for industrial applications it is of interest to use flat specimens at very high frequency in the gigacycle regime. In this work, thin flat sheet, with 1.2 mm thickness of a complex phase ferrite-martensitic steels were considered for carrying out fatigue tests at high frequency (20 kHz up to the gigacycle regime (>109 cycles. The crack initiation tests were carried out with water cooling, while the crack growth test were carried out in laboratory air at room temperature. All the tests were carried out under loading ratio R=-1. To do that, special designs of specimens were made and computed using FEM for defining the stress amplitude for endurance tests. Special attachments for specimens to the ultrasonic system’s horn were enhanced. A particular FEM computing of the stress intensity range on crack growth specimens was carried out for determining the specimen dimensions and an equation that defines the stress intensity range as a function of the harmonic displacement amplitude, dynamic Young’s modulus, material density and crack length. Detailed procedures and fatigue results are presented in this paper.

  3. Mechanical characterization of auxetic stainless steel thin sheets with reentrant structure

    Science.gov (United States)

    Lekesiz, H.; Bhullar, S. K.; Karaca, A. A.; Jun, M. B. G.

    2017-08-01

    Smart materials in auxetic form present a great potential for various medical applications due to their unique deformation mechanisms along with durable infrastructure. Both analytical and finite element (FE) models are extensively used in literature to characterize mechanical response of auxetic structures but these structures are mostly thick enough to be considered as bulk material and 3D inherently. Auxetic plates in very thin form, a.e. foil, may bring numerous advantages such as very light design and better biodegradability when needed. However, there is a gap in literature on mechanical characterization of auxetic thin plates. In this study, structural analysis of very thin auxetic plates under uniaxial loading is investigated using both FE method and experimental method. 25 μm thick stainless steel (316L) plates are fabricated with reentrant texture for three different unit cell dimensions and tested under uniaxial loading using universal testing machine. 25 and 50 μm thick sheets with same cell dimensions were analyzed using implicit transient FE model including strain hardening and failure behaviors. FE results cover all the deformation schemes seen in actual tests and total deformation level matches with test results. Effect of plate thickness and cell geometry on auxetic behavior is discussed in detail using FE results. Finally, based on FE analysis results, an optimum geometry for prolonged auxetic behavior, high flexibility and high durability is suggested for future potential applications.

  4. Experimental analysis and theoretical predictions of the limit strains of a hot-dip galvanized interstitial-free steel sheet

    Directory of Open Access Journals (Sweden)

    Maria Carolina dos Santos Freitas

    2013-04-01

    Full Text Available In this work, the formability of a hot-dip galvanized interstitial-free (IF steel sheet was evaluated by means of uniaxial tensile and Forming Limit Curve (FLC tests. The FLC was defined using the flat-bottomed Marciniak's punch technique, where the strain analysis was made using a digital image correlation software. A plastic localization model was also proposed wherein the governing equations are solved with the help of the Newton's method. The investigated hot-dip galvanized IF steel sheet presented a very good formability level in the deep-drawing range consistent with the measured Lankford values. The predicted limit strains were found to be in good agreement with the experimental data of the hot-dip galvanized IF steel sheet owing to the definition of the localization model geometrical imperfection as a function of the experimental surface roughness evolution and, in particular, to the yield surface flattening near to the plane-strain stress state authorized by the adopted yield criterion.

  5. Effect of elastic-plastic behavior of coating layer on drawability and frictional characteristic of galvannealed steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seong Won; Lee, Jung Min [Korea Institute of Industrial Technology, Jinju (Korea, Republic of); Joun, Man Soo [Gyeongsang National University, Jinju (Korea, Republic of); Kim, Dong Hwan [International University of Korea, Jinju (Korea, Republic of)

    2016-07-15

    During a galvannealed sheet metal forming, the failures of coating layers (powdering, flaking and cracking) frequently affect the strain state of sheets and deteriorate the frictional characteristic between sheets and tools. Two FE-models in this study were suggested to investigate the effects of the mechanical behavior of coating layers on the formability and friction of the coated steel sheets in FE analysis; the first is one-layer model to express the coated sheet as one stress-strain curve and the second is a multiple-layer model which is composed of substrates and coating layers, separately. First, the frictional properties and the formability of the coated sheets were experimentally investigated using a cup deep-drawing trial. After, the drawing process was simulated by FE analysis of the two models. In the multiplelayer model, the mechanical behavior of the coating is defined as a stress-strain curve which was determined using the nanoindentation test of the coating, its FE analysis and artificial neural network method. The result showed that the multiple-layer model provides more accuracy predictions of drawing loads than the one-layer model in the FE analysis, compared to the actual cup drawing test.

  6. DEVELOPING A KNOWLEDGE-DASED DECISION STEM TO SELECT THE STEELS OF DIESFOR SHEET-METAL FORMING

    Directory of Open Access Journals (Sweden)

    EMİN GÜNDOĞAR

    1997-12-01

    Full Text Available Material selection is a problem solving and decison making process. In the selection of die materials, some points are very important. For this reasons, daıabases are not enough to select the steels of dies for sheet metal in themselves. They do not incorporate data relating to all of the contributin g factors needed for quantitive interpretations. To solve the user's problem are requried expertises and knowledge obtained from experts. In this study, a knowledg e-hased decision making system is introduced which is included the knowledge and experiences of the experts that subject fo ı med from rules and there is a database inc l uding the cbaracterictics of die steels. · In this syste m also comprises �ision making mechanizm that selects suitable die steels by using user inte rface.

  7. Metallurgical characteristics and failure mode transition for dissimilar resistance spot welds between ultra-fine grained and coarse-grained low carbon steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Khodabakhshi, F.; Kazeminezhad, M., E-mail: mkazemi@sharif.edu; Kokabi, A.H.

    2015-06-18

    We studied the microstructure and mechanical characteristics of spot welded specimens, fabricated from low carbon steel sheets with different microstructures. Both ultra-fine grained (UFG) steel sheet and coarse grained (CG) steel sheet were used. The refined microstructure of the UFG steel has been produced by severe plastic deformation (SPD) using the constrained groove pressing (CGP) method. The grain size of the base metals was approximately 260 nm and 30 µm in diameter, respectively, in the UFG and CG steels. Examining the microstructure of a cross section cut through the spot weld reveals a similar grain size and phase distribution in the nugget on both the sides of the initial interface between sheets. Some recrystallization is observed in the heat affected zone on the UFG side as previously reported after the welding of symmetrical UFG–UFG spot welded specimens. The same energy deposit produces larger nuggets after the spot welding of UFG steels. Moreover, the hardness distribution across the nugget changes after welding on both sides of the initial (UFG/CG) interface. This effect is presently attributed to a change in the solidification, cooling rate and tempering after welding, likely because the higher resistance of UFG steel sheets increases the heat release by the Joule effect during spot welding. These changes in the mechanical behavior modify the transition between the interfacial failure (IF) and pull out failure (PF) mode with respect to energy deposit.

  8. Effects of heat input on mechanical properties of metal inert gas welded 1.6 mm thick galvanized steel sheet

    Science.gov (United States)

    Rafiqul, M. I.; Ishak, M.; Rahman, M. M.

    2012-09-01

    It is usually a lot easier and less expensive to galvanize steel before it is welded into useful products. Galvanizing afterwards is almost impossible. In this research work, Galvanized Steel was welded by using the ER 308L stainless steel filler material. This work was done to find out an alternative way of welding and investigate the effects of heat input on the mechanical properties of butt welded joints of Galvanized Steel. A 13.7 kW maximum capacity MIG welding machine was used to join 1.6 mm thick sheet of galvanized steel with V groove and no gap between mm. Heat inputs was gradually increased from 21.06 to 25.07 joules/mm in this study. The result shows almost macro defects free welding and with increasing heat input the ultimate tensile strength and welding efficiency decrease. The Vickers hardness also decreases at HAZ with increasing heat input and for each individual specimen; hardness was lowest in heat affected zone (HAZ), intermediate in base metal and maximum in welded zone. The fracture for all specimens was in the heat affected zone while testing in the universal testing machine.

  9. Determination of instability of a DP 980 steel sheet under different stress states based on experiment and theoretical models

    Directory of Open Access Journals (Sweden)

    Song Hong-Wu

    2016-01-01

    Full Text Available It is generally accepted that the formability of sheet metal is limited by the onset of instability which can be described by forming limit diagram (FLD in ε1-ε2 space. Common tests for FLD data usually cover strain ratio range from uniaxial to equal biaxial stretching, −1/2 ≤ ε2/ε1 ≤ 1. In this paper a new design of cruciform type specimen for uniaxial stretching is proposed to test formability with strain ratios in the range from shear to tension, −1 ≤ ε2/ε1 ≤ −1/2 which can be controlled by the geometry parameters. The forming limit of a DP 980 steel sheet was determined using both conventional method and proposed specimen with strain ratios from −1 ≤ ε2/ε1 ≤ 1. Then the experimental results were drawn in both ε1− ε2 and εeq−σm/σeq spaces, and the predicted results based on Hill, Swift, M-K, and Hora instability models were compared with the experimental ones. The formability features of the studied steel in whole strain ratio range and differences among the investigated theoretical models were finally discussed. The results indicate that the M-K instability model shows better prediction of the studied steel compared to the other models investigated in this research.

  10. Investigation on dissimilar laser welding of advanced high strength steel sheets for the automotive industry

    Energy Technology Data Exchange (ETDEWEB)

    Rossini, M., E-mail: matteo.rossini@unibz.it [Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano (Italy); Spena, P. Russo, E-mail: pasquale.russospena@unibz.it [Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano (Italy); Cortese, L., E-mail: luca.cortese@unibz.it [Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano (Italy); Matteis, P., E-mail: paolo.matteis@polito.it [Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy); Firrao, D., E-mail: donato.firrao@polito.it [Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy)

    2015-03-25

    To support the use of advanced high strength steels in car body design and fabrication, an investigation was carried out on dissimilar butt laser welding between TWinning Induced Plasticity (TWIP) steels, Dual Phase (DP) steels, hot stamping boron (22MnB5) steels, and TRansformation Induced Plasticity (TRIP) steels. The base materials and the weldments were fully characterized by means of metallography, microhardness, and tensile tests. Digital image analysis was also used to provide additional information on the local strain field in the joint during the tensile tests. Fractographic examination was finally performed on the fracture surfaces of the tensile samples. The dissimilar joints between the DP, 22MnB5, and TRIP steels exhibit good resistance properties. On the contrary, the dissimilar joints encompassing the TWIP steel exhibit poor mechanical strength and fail along the weld seam by intergranular fracture, probably due to presence of Mn segregations. Therefore, the laser welding of TWIP steel with other advanced high strength steels is not recommended without the use of proper metal fillers. Dissimilar laser welding of DP, TRIP and 22MnB5 combinations, on the contrary, can be a solution to assemble car body parts made of these steel grades.

  11. Two-beam Laser Brazing of Thin Sheet Steel for Automotive Industry Using Cu-base Filler Material

    Science.gov (United States)

    Mittelstädt, C.; Seefeld, T.; Reitemeyer, D.; Vollertsen, F.

    This work shows the potential of two-beam laser brazing for joining both Zn-coated steel and 22MnB5. Brazing of Zn-coated steel sheets using Cu-Si filler wire is already state of the art in car manufacturing. New press-hardened steels like 22MnB5 are more and more used in automotive industry, offering high potential to save costs and improve structural properties (reduced weight / higher stiffness). However, for joining of these ultra-high strength steels investigations are mandatory. In this paper, a novel approach using a two-beam laser brazing process and Cu-base filler material is presented. The use of Cu-base filler material leads to a reduced heat input, compared to currently applied welding processes, which may result in benefits concerning distortion, post processing and tensile strength of the joint. Reliable processing at desired high speeds is attained by means of laser-preheating. High feed rates prevent significant diffusion of copper into the base material.

  12. Surface investigation and tribological mechanism of a sulfate-based lubricant deposited on zinc-coated steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Timma, Christian, E-mail: christian.timma@thyssenkrupp.com [ThyssenKrupp Steel Europe AG, Technology & Innovation, Kaiser-Wilhelm Str. 100, 47166 Duisburg (Germany); University of Duisburg-Essen, Faculty of Chemistry, CENIDE, Universitätsstraße 7, 45141 Essen (Germany); Lostak, Thomas; Janssen, Stella; Flock, Jörg [ThyssenKrupp Steel Europe AG, Technology & Innovation, Kaiser-Wilhelm Str. 100, 47166 Duisburg (Germany); Mayer, Christian [University of Duisburg-Essen, Faculty of Chemistry, CENIDE, Universitätsstraße 7, 45141 Essen (Germany)

    2016-12-30

    Highlights: • Skin-passed hot-dip galvanized (HDG-) steel sheets were coated with (NH{sub 4}){sub 2}SO{sub 4} in a common roll-coating method. • A formation of (NH{sub 4}){sub 2}Zn(SO{sub 4}) * xH{sub 2}O was observed and the reaction mainly occurred in the skin-passed areas of the surface. • Sulfate coated samples reveal a superior friction behaviour in oil-like conditions compared non-sulfated specimen. - Abstract: Phosphatation is a well-known technique to improve friction and wear behaviour of zinc coated steel, but has a variety of economic and ecologic limitations. In this study an alternative coating based on ammonium sulfate ((NH{sub 4}){sub 2}SO{sub 4}) is applied on skin-passed hot-dip galvanized steel sheets in order to investigate its surface chemical and tribological behaviour in a Pin-on-Disk Tribometer. Raman- and X-ray photoelectron spectroscopic results revealed a formation of ammonium zinc sulfate ((NH{sub 4}){sub 2}Zn(SO{sub 4}){sub 2} * xH{sub 2}O) on the surface, which is primarily located in the skin-passed areas of the steel material. Sulfate coated samples exhibited a superior friction behaviour in Pin-on-Disk Tests using squalane as a model substance for oil-like lubricated conditions and a formation of a thin lubrication film is obtained in the wear track. Squalane acts as a carrier substance for ammonium zinc sulfate, leading to an effective lubrication film in the wear track.

  13. 76 FR 49726 - Continuation of Antidumping and Countervailing Duty Orders: Stainless Steel Sheet and Strip in...

    Science.gov (United States)

    2011-08-11

    ... between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a... the scope. This product is defined as a non-magnetic stainless steel manufactured to American Society... stainless steel strip in coils used in the production of textile cutting tools (e.g., carpet knives).\\4...

  14. 78 FR 79667 - Stainless Steel Sheet and Strip in Coils From Japan: Initiation of Expedited Changed...

    Science.gov (United States)

    2013-12-31

    ... iron, in widths 228.6 mm or less, and a thickness between 0.127 and 1.270 mm. It exhibits magnetic... defined as a non-magnetic stainless steel manufactured to American Society of Testing and Materials (ASTM... the production of textile cutting tools (e.g., carpet knives).\\7\\ This steel is similar to AISI grade...

  15. Page 1 3.x: On the formability of sheet Steels 97. Table 4. Values of ...

    Indian Academy of Sciences (India)

    r value is usually associated with a high Ar value. In the case of ferritic stainless steel. (cold-rolled and annealed) a high f value of 208 was observed (table 2). This is presumably due to the very sharp 111 type texture which develops (Miyaji and. Watanabe 1980) in such steel by the mechanism of in situ recrystallization.

  16. Experimental and Numerical Investigations of Applying Tip-bottomed Tool for Bending Advanced Ultra-high Strength Steel Sheet

    Science.gov (United States)

    Mitsomwang, Pusit; Borrisutthekul, Rattana; Klaiw-awoot, Ken; Pattalung, Aran

    2017-09-01

    This research was carried out aiming to investigate the application of a tip-bottomed tool for bending an advanced ultra-high strength steel sheet. The V-die bending experiment of a dual phase steel (DP980) sheet which had a thickness of 1.6 mm was executed using a conventional bending and a tip-bottomed punches. Experimental results revealed that the springback of the bent worksheet in the case of the tip-bottomed punch was less than that of the conventional punch case. To further discuss bending characteristics, a finite element (FE) model was developed and used to simulate the bending of the worksheet. From the FE analysis, it was found that the application of the tip-bottomed punch contributed the plastic deformation to occur at the bending region. Consequently, the springback of the worksheet reduced. In addition, the width of the punch tip was found to affect the deformation at the bending region and determined the springback of the bent worksheet. Moreover, the use of the tip-bottomed punch resulted in the apparent increase of the surface hardness of the bent worksheet, compared to the bending with the conventional punch.

  17. On modelling of shear fracture in deep drawing of a high-strength dual-phase sheet steel

    Science.gov (United States)

    Behrens, B.-A.; Bonk, C.; Peshekhodov, I.

    2017-09-01

    The paper presents application of fracture behaviour characterisation results of a dual-phase sheet steel DP600 to an FEA of its deep-drawing for shear fracture prediction. The characterisation results were obtained with the help of a characterisation method based on a tensile test on a novel butterfly specimen and published previously by the authors. The aim of the present paper is to evaluate that characterisation method on a deep-drawing process. Based on the previous results of the authors, the fracture behaviour is modelled here with the help of the modified Mohr-Coloumb fracture model. The obtained FEA results reveal that shear fracture of the studied material is predicted too early by the used MMC fracture model. A novel adjustment of the model is proposed yielding infinitely high fracture strains at strongly pressure-superimposed stress states. As it is often the case in the state-of-the-art fracture characterisation of high-strenght sheet steels, such stress states were not tested during the previously performed fracture characterisation but occur during the studied deep drawing process. With the help of the adjusted MMC fracture model, it is possible to predict the crack initiation moment very accurately and the crack initiation location sufficiently accurately.

  18. Interlocking multi-material components made of structured steel sheets and high-pressure die cast aluminium

    Science.gov (United States)

    Senge, S.; Brachmann, J.; Hirt, G.; Bührig-Polaczek, A.

    2017-10-01

    Lightweight design is a major driving force of innovation, especially in the automotive industry. Using hybrid components made of two or more different materials is one approach to reduce the vehicles weight and decrease fuel consumption. As a possible way to increase the stiffness of multi-material components, this paper presents a process chain to produce such components made of steel sheets and high-pressure die cast aluminium. Prior to the casting sequence the steel sheets are structured in a modified rolling process which enables continuous interlocking with the aluminium. Two structures manufactured by this rolling process are tested. The first one is a channel like structure and the second one is a channel like structure with undercuts. These undercuts enable the formation of small anchors when the molten aluminium fills them. The correlation between thickness reduction during rolling and the shape of the resulting structure was evaluated for both structures. It can be stated that channels with a depth of up to 0.5 mm and a width of 1 mm could be created. Undercuts with different size depending on the thickness reduction could be realised. Subsequent aluminium high-pressure die casting experiments were performed to determine if the surface structure can be filled gap-free with molten aluminium during the casting sequence and if a gap-free connection can be achieved after contraction of the aluminium. The casting experiments showed that both structures could be filled during the high-pressure die casting. The channel like structure results in a gap between steel and aluminium after contraction of the cast metal whereas the structure with undercuts leads to a good interlocking resulting in a gap-free connection.

  19. Dual-phase steel sheets under cyclic tension-compression to large strains: Experiments and crystal plasticity modeling

    Science.gov (United States)

    Zecevic, Milovan; Korkolis, Yannis P.; Kuwabara, Toshihiko; Knezevic, Marko

    2016-11-01

    In this work, we develop a physically-based crystal plasticity model for the prediction of cyclic tension-compression deformation of multi-phase materials, specifically dual-phase (DP) steels. The model is elasto-plastic in nature and integrates a hardening law based on statistically stored dislocation density, localized hardening due to geometrically necessary dislocations (GNDs), slip-system-level kinematic backstresses, and annihilation of dislocations. The model further features a two level homogenization scheme where the first level is the overall response of a two-phase polycrystalline aggregate and the second level is the homogenized response of the martensite polycrystalline regions. The model is applied to simulate a cyclic tension-compression-tension deformation behavior of DP590 steel sheets. From experiments, we observe that the material exhibits a typical decreasing hardening rate during forward loading, followed by a linear and then a non-linear unloading upon the load reversal, the Bauschinger effect, and changes in hardening rate during strain reversals. To predict these effects, we identify the model parameters using a portion of the measured data and validate and verify them using the remaining data. The developed model is capable of predicting all the particular features of the cyclic deformation of DP590 steel, with great accuracy. From the predictions, we infer and discuss the effects of GNDs, the backstresses, dislocation annihilation, and the two-level homogenization scheme on capturing the cyclic deformation behavior of the material.

  20. Surface investigation and tribological mechanism of a sulfate-based lubricant deposited on zinc-coated steel sheets

    Science.gov (United States)

    Timma, Christian; Lostak, Thomas; Janssen, Stella; Flock, Jörg; Mayer, Christian

    2016-12-01

    Phosphatation is a well-known technique to improve friction and wear behaviour of zinc coated steel, but has a variety of economic and ecologic limitations. In this study an alternative coating based on ammonium sulfate ((NH4)2SO4) is applied on skin-passed hot-dip galvanized steel sheets in order to investigate its surface chemical and tribological behaviour in a Pin-on-Disk Tribometer. Raman- and X-ray photoelectron spectroscopic results revealed a formation of ammonium zinc sulfate ((NH4)2Zn(SO4)2 * xH2O) on the surface, which is primarily located in the skin-passed areas of the steel material. Sulfate coated samples exhibited a superior friction behaviour in Pin-on-Disk Tests using squalane as a model substance for oil-like lubricated conditions and a formation of a thin lubrication film is obtained in the wear track. Squalane acts as a carrier substance for ammonium zinc sulfate, leading to an effective lubrication film in the wear track.

  1. Laser-Assisted Sheet Metal Working of High Strength Steels in Serial Production

    OpenAIRE

    Brecher, Christian; Emonts, Michael; Eckert, Markus

    2011-01-01

    Within the sheet metal working industry the demand for thinner sheet materials with very high strength is growing due to the increasing need to save energy and a responsible use of natural resources. The high strength and the low ductility restricts using state of art technology to sheer, bend, emboss or deep draw parts with the needed complexity and quality. The Fraunhofer IPT developed a combination of laser-assisted preheating and conventional punching to a new hybrid technology which allo...

  2. USING THE VIDEOEXTENSOMETRY AND UCI - HARDNESS FOR MONITORING OF AUTOMOTIVE STEEL SHEETS

    Directory of Open Access Journals (Sweden)

    Mária Mihaliková

    2011-09-01

    Full Text Available The paper deals with examination of relation between the hardness and the size of plastic zone during the tensile loading. UCI (Ultrasonic Contact Impedance micro-hardness method was used for hardness measurements. Deformation was evaluated by non-contact extensometry method – videoextensometry. The result present existence of the power lawl relation between hardness and plastic deformation: HV = HV(p+ kE^a. Hot rolled sheet and thin automotive sheet were investigated.

  3. Comparative Study on Damage Evolution during Sheet Metal Forming of Steels DP600 and DP1000

    Science.gov (United States)

    Münstermann, S.; Lian, J.; Pütz, F.; Könemann, M.; Brinnel, V.

    2017-09-01

    Two different dualphase steels of significantly different strength properties are compared with respect to microstructural configuration, chemical composition, mechanical properties, and ductile damage mechanisms. The investigated steel grades DP600 and DP1000 show remarkable differences in terms of martensite phase fractions, yield and ultimate tensile strength, and ductile damage evolution behaviour. In particular it turns out that steel DP600 experiences a relatively early ductile damage initiation, but only a moderate rate of damage evolution, whereas for steel DP1000, contrary behaviour is observed. This steel shows a comparably late ductile damage initiation with rapid subsequent damage evolution. This behaviour is expressed by the ratio of fracture strain over strain at damage initiation. Its origin lies in both the martensite phase fraction and the individual strength properties of the ferritic and the martensitic phases, which will provoke inhomogeneous plastic strain distributions in the materials’ microstructures. The more pronounced these differences are, the higher the local plastic strain peaks become, and the earlier ductile damage initiation happens. Nevertheless, with decreasing strength of the ferritic phase, its ability to withstand even large plastic strains without fracturing is strongly promoted, so that the fracture strain in steel DP600 can be shifted to higher values even though the material has undergone early damage initiation.

  4. Assessment of the Critical Parameters Influencing the Edge Stretchability of Advanced High-Strength Steel Sheet

    Science.gov (United States)

    Pathak, N.; Butcher, C.; Worswick, M.

    2016-11-01

    The edge formability of ferritic-martensitic DP (dual-phase) and ferritic-bainitic CP (complex-phase) steels was evaluated using a hole expansion test for different edge conditions. Hole expansion tests involving the standard conical punch as well as a custom flat punch were performed to investigate formability when the hole is expanded out-of-plane (conical punch) and in-plane using the flat punch. A range of edge conditions were considered, in order to isolate the influence of a range of factors thought to influence edge formability. The results demonstrate that work hardening and void damage at the sheared edge govern formability, while the sheared surface quality plays a minor or secondary role. A comparison of the edge stretching limits of DP and CP steels demonstrates the advantages of a ferritic-bainitic microstructure for forming operations with severe local deformation as in a stretch-flanging operation. A comparison of a traditional DP780 steel with a CP steel of similar strength showed that the edge stretching limit of the CP steel was three times larger than that of the DP780.

  5. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    Science.gov (United States)

    Thomas, Gareth; Ahn, Jae-Hwan; Kim, Nack-Joon

    1986-01-01

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar.sub.3 temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics.

  6. Joining of Low-Carbon Steel Sheets with Al-Based Weld

    Directory of Open Access Journals (Sweden)

    Boczkal G.

    2016-03-01

    Full Text Available The analysis of the connection steel/Al/steel made by resistance welding was performed. The used low-carbon steel had low content of carbon and other elements, aluminum was of 99.997 wt.% Al purity. Formation of various FeAl intermetallic phases found in the phase diagram depending on the duration of the process was analyzed. Two distinctively different types of structure depending on time of welding were observed: 1 hypoeutectic structure for samples processed for 5 s, and 2 eutectic structure for samples processed for 10 s and more. The shear test showed increase of mechanical properties of the connection for the samples welded 10 s.

  7. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    Science.gov (United States)

    Thomas, G.; Ahn, J.H.; Kim, N.J.

    1986-10-28

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar[sub 3] temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics. 3 figs.

  8. Study and numerical analysis on formability of quenching and partitioning steel sheets of auto-body

    Science.gov (United States)

    Hu, Xing; Liu, Yifan; Zhu, Lin

    2013-05-01

    Advanced high strength steel is the basic structure material for lightweight design and safety enhancement for automobile industry. Quenching and partitioning steel is a recently developed kind of low carbon and low alloy material with retained Austenite for the requirements of both high strength and high ductility. This paper focuses on the formability of a hinge pillar for some car under numerical modelling analysis. The results show that QP980 has an equal elongation comparing with DP590. Moreover, the numerical modelling results of QP980 are more sensitive to the selection of yielding equation comparing with DP590.

  9. Quantification of Residual Stresses in Hot Rolled Steel Sheets by the Hole Drilling Method

    Directory of Open Access Journals (Sweden)

    Trebuňa, F.

    2007-01-01

    Full Text Available The paper deals with the problems of quantification of residual stresses in hot rolled sheets produced under various regimes. On the base of stress distribution along width and thickness of the belt is pointed out on possibilities of belt deformation from the plane as a result of action of torsional moment as an integral internal quantity in cross-section. For the non-uniformly distributed stresses along the thickness of the sheet the new method for residual stresses determination was developed. Application of the method is described in the paper.

  10. Laser-Assisted Sheet Metal Working of High Strength Steels in Serial Production

    Science.gov (United States)

    Brecher, Christian; Emonts, Michael; Eckert, Markus

    Within the sheet metal working industry the demand for thinner sheet materials with very high strength is growing due to the increasing need to save energy and a responsible use of natural resources. The high strength and the low ductility restricts using state of art technology to sheer, bend, emboss or deep draw parts with the needed complexity and quality. The Fraunhofer IPT developed a combination of laser-assisted preheating and conventional punching to a new hybrid technology which allows to shear, bend, emboss and draw high strength materials with a high quality and complexity in a serial production.

  11. Dual beam Nd:YAG laser welding: influence of lubricants to lap joint welding of steel sheets

    Science.gov (United States)

    Geiger, M.; Merklein, M.; Otto, A.; Blankl, A.

    2007-05-01

    Laser welding is applied in large-volume production since the late eighties and has revolutionized the possibilities of designing and engineering products. Nevertheless, problems appear during application because the operational conditions in industrial environments fluctuate and can influence the welding process negatively. Contaminations, like lubricants and organic solids, are an example of changing conditions in laser beam welding. If a lap joint is welded, these materials have to be removed from the sheets, otherwise pores and surface failures may appear due to keyhole instabilities induced by uncontrolled outgassing. One possibility for solving this problem is the use of two separate laser beams. For producing these two beams several systems are available for all different kind of lasers. A bifocal optic is such a solution for an Nd:YAG laser. By using this system, the laser beam is divided after collimation with a prism. Afterwards the two beams are focussed with a lens to the surface of the sheet and two single spots are produced. If the distance between the two spots is low, one common, elliptical keyhole is created. With this system two different welding strategies are possible. The spots can be oriented parallel or normal to the feed direction. For stabilizing the laser welding of contaminated steel sheets the parallel arrangement is better, because the amount of contamination is nearly the same as in single spot welding but the total volume of the keyhole is greater and so pressure variations due to uncontrolled evaporation of contaminations are lower. In order to prove this theory and to determine the exact effects some investigations were made at the Chair of Manufacturing Technology of the University of Erlangen-Nuremberg. A 4 kW Nd:YAG laser with a beam parameter product of 25 mm*mrad and a focal distance of 200 mm was used to weld two 1 mm DC04 steel sheets together with a lap joint. Between the sheets a deep drawing lubricant, Castrol FST 6, was

  12. Explosive Forming of Low Carbon Steel Sheet into a Stepped Disc Shape

    OpenAIRE

    Balasubramanian, S.; S. Sarvat Ali; E.S. Bhagiradha Rao

    1984-01-01

    This paper deals with the explosive forming of deep drawing quality steel into a two stepped disc type shape. An attempt has been made to predict the forming parameters from theoretical considerations by equating the disc shape with an equivalent dome. Results of forming this shape in a single stage vis-a-vis forming in two stages are compared.

  13. Tooling solutions for sheet metal forming and punching of lean duplex stainless steel

    DEFF Research Database (Denmark)

    Wadman, Boel; Madsen, Erik; Bay, Niels

    2012-01-01

    .4509 and lean duplex EN1.4162 in a production designed for austenitic stainless steels, such as EN1.4301 and 1.4401. The result is a guideline that summarizes how stainless material properties may affect tool degradation, and suggests tool solutions for reduced production disturbances and tool maintenance cost....

  14. Experimental and numerical study on optimization of the single point incremental forming of AINSI 304L stainless steel sheet

    Science.gov (United States)

    Saidi, B.; Giraud-Moreau, L.; Cherouat, A.; Nasri, R.

    2017-09-01

    AINSI 304L stainless steel sheets are commonly formed into a variety of shapes for applications in the industrial, architectural, transportation and automobile fields, it’s also used for manufacturing of denture base. In the field of dentistry, there is a need for personalized devises that are custom made for the patient. The single point incremental forming process is highly promising in this area for manufacturing of denture base. The single point incremental forming process (ISF) is an emerging process based on the use of a spherical tool, which is moved along CNC controlled tool path. One of the major advantages of this process is the ability to program several punch trajectories on the same machine in order to obtain different shapes. Several applications of this process exist in the medical field for the manufacturing of personalized titanium prosthesis (cranial plate, knee prosthesis...) due to the need of product customization to each patient. The objective of this paper is to study the incremental forming of AISI 304L stainless steel sheets for future applications in the dentistry field. During the incremental forming process, considerable forces can occur. The control of the forming force is particularly important to ensure the safe use of the CNC milling machine and preserve the tooling and machinery. In this paper, the effect of four different process parameters on the maximum force is studied. The proposed approach consists in using an experimental design based on experimental results. An analysis of variance was conducted with ANOVA to find the input parameters allowing to minimize the maximum forming force. A numerical simulation of the incremental forming process is performed with the optimal input process parameters. Numerical results are compared with the experimental ones.

  15. Metal release from stainless steel powders and massive sheets--comparison and implication for risk assessment of alloys.

    Science.gov (United States)

    Hedberg, Yolanda; Mazinanian, Neda; Odnevall Wallinder, Inger

    2013-02-01

    Industries that place metal and alloy products on the market are required to demonstrate that they are safe for all intended uses, and that any risks to humans, animals or the environment are adequately controlled. This requires reliable and robust in vitro test procedures. The aim of this study is to compare the release of alloy constituents from stainless steel powders of different grades (focus on AISI 316L) and production routes into synthetic body fluids with the release of the same metals from massive sheets in relation to material and surface characteristics. The comparison is justified by the fact that the difference between massive surfaces and powders from a metal release/dissolution and surface perspective is not clearly elucidated within current legislations. Powders and abraded and aged (24 h) massive sheets were exposed to synthetic solutions of relevance for biological settings and human exposure routes, for periods of up to one week. Concentrations of released iron, chromium, nickel, and manganese in solution were measured, and the effect of solution pH, acidity, complexation capacity, and proteins elucidated in relation to surface oxide composition and its properties. Implications for risk assessments based on in vitro metal release data from alloys are elucidated.

  16. Formability evaluation for hot-rolled HB780 steel sheet based on 3-D non-quadratic yield function

    Science.gov (United States)

    Kim, Wonjae; Koh, Youngwoo; Kim, Hyunki; Chung, Youn-Il; Lee, Myoung-Gyu; Chung, Kwansoo

    2017-05-01

    A common practice to evaluate formability in the typical sheet metal forming process is to measure hardening behavior and a forming limit diagram as separate material properties, and perform numerical forming simulations utilizing various yield functions. The measured forming limit diagram is applied as the failure criterion. However, the performance of material properties such as hardening behavior and yield functions in predicting strain localization in the simple tension and forming limit diagram tests is seldom validated before their application to forming simulation. In this study, a new numerical formability evaluation procedure was proposed, in which not only hardening behavior but also measured forming limit data were employed in characterizing the input data for the hardening behavior and the yield function. Besides, strain localization was directly monitored to determine failure without employing any forming limit criterion. The new procedure was applied for rather thick advanced high strength hot-rolled steel sheet so that 3-D continuum elements were utilized along with 3-D non-quadratic Hosford and quadratic Hill yield functions.

  17. Development of 440MPa grade galvannealed steel sheet for laser irradiation strengthening; Laser shosha kyokayo 440 MPa kyu GA koban no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, M.; Makii, K.; Soshiroda, T.; Inoue, T. [Kobe Steel, Ltd., Kobe (Japan); Tomioka, Y.; Nakamura, S.; Nakajima, H.; Sato, A.; Aiko, H. [Toyota Motor Corp., Aichi (Japan)

    1995-04-20

    While weight reduction is being advanced on automotive members, material strength is also improved. However, a problem also exists that the processibility decreases on the other hand. A new method to make these two elements compatible is being developed that materials are strengthened by laser irradiation after the materials have been formed by press. This paper elucidates design parameters for components of steels suitable for laser strengthening from a metallurgical viewpoint, and describes development of sheet steels. A C-Mn steel with a thickness of 1.4 mm was used to perform tensile tests and investigate the structure and hardness to study the effect of the laser irradiation. As a result, it was found that high-accuracy evaluation can be achieved with the K1 value (C% {times} Mn%) which was introduced newly as a material design parameter for strength increase. Development was made on a 440-MPa grade galvannealed sheet steel that has the same processibility as the conventional steels and can achieve as large increase in tensile strength as more than 30% relative to the member strength, by properly balancing the carbon amount and the Mn amount. The steel was verified to be free of problems in practical use both in the fatigue characteristics and the delayed fracture resistant characteristics. 4 refs., 12 figs., 2 tabs.

  18. Analysis of properties laser welded RAK 40/70 steel sheets

    Science.gov (United States)

    Evin, E.; Tomáš, M.; Fujda, M.

    2017-11-01

    Both, the ecological production and operation of vehicles demand using such materials for deformation zones’ structural parts, which show some specific properties and use innovative technologies to process them. Specific requirements for functionality (strength, stiffness, deformation work, fatigue properties) are closely linked to processability (formability). In the paper are presented results for multiphase TRIP steel RAK40/70 when welded by pulse solid-state fiber laser YLS-5000. Based on microstructure analysis in the fusion zone and heat affected zone the welding parameters were optimised. The influence of laser welding on the strength and deformation properties was verified by characteristics of strength, stiffness and deformation work, as they were calculated from mechanical properties measured by tensile test and three-point bending test. The knowledge gathered in the field of laser welding influence on the strength and deformation properties of multiphase TRIP steel RAK40/70 should help designers when design the lightweight structural parts of the car body.

  19. An Investigation of The Reticulated Foam - Perforated Steel Sheet Sandwich Structure As A Blast Mitigation Media

    Science.gov (United States)

    Nguyen, Thuy-Tien Ngoc; Proud, William; Institute of Shock Physics, Imperial College London Collaboration; Royal British Legion CentreBlast Injury Studies at Imperial College London Collaboration

    2015-06-01

    Explosions have always been the main cause of injuries during battles and conflicts, with improvised explosive devices (IEDs) becoming more and more common nowadays. In this paper, the interaction between blast waves and sandwich structures of reticulated foam and perforated sheets, with varying thickness and configuration, is studied using an air-driven shock tube apparatus. The mitigation effects for primary blast injuries of these structures are discussed in terms of pulse shape, pressure magnitude as well as shock impulse. Schlieren photography together with other high-speed imaging was also used to visually investigate the matter. The results show that lower open area of perforated sheet and increased thickness of foam offer best protection. However, below a threshold thickness, no mitigation is seen. The Institute of Shock Physics acknowledges the support of AWE, Aldermaston, UK and Imperial College London. The Centre for Blast Injury Studies acknowledges the support of the Royal British Legion and Imperial College London.

  20. A Fixture for Compressive Tests of Thin Sheet Metal Between Lubricated Steel Guides

    Science.gov (United States)

    1946-04-01

    figure, The width of the paok was reduced about 1/64 inch by light cuts with a surface grinden apd the paok was turned . NACA TN No. 1022 5 ● over and was...RESULTSOFCOMPRESSIVET STSOF0.054-INCH1025CARBONSTEELSHEET, ~NSVE&E SPECIWZNS peoimen number CIT CF6T C21T C22T KindOf testor lateral support Paok -do-- Steel

  1. Influence of Thermal Treatment on Magnetic Properties of Steel Sheet Material Utilised in Cable Routing System

    Directory of Open Access Journals (Sweden)

    Elemir Usak

    2013-01-01

    Full Text Available The influence of relax annealing aimed at removal of the residual stresses (so-called stress-relief annealing on various magnetic parameters, such as the relative magnetic amplitude permeability, coercivity, remanent flux density, etc. is discussed. Samples of steel cable tray material which is a part of commercially available cable routing system were investigated in order to find information about the properties important from the point of view of EMC requirements in extremely demanding industrial environment.

  2. Experimental Investigation on Micro-Welding of Thin Stainless Steel Sheet by Fiber Laser

    OpenAIRE

    Mohd I.S. Ismail; Yasuhiro Okamoto; Akira Okada; Yoshiyuki Uno

    2011-01-01

    Problem statement: The miniaturization of components plays an important role for manufacturing in electrical and electronic industries. Therefore, the joining technology of thin metal sheets has been strongly required. Laser welding with micro-beam and high-speed scanning is a promising solution in micro-welding, because it has high-potential advantages in welding heat sensitive components with precise control of heat input and minimal thermal distortion. Approach: In this study, the characte...

  3. Estimation of tensile shear strength of spot welded joint of steel sheets. 1st report. Resistance spot welded joint strength of steel sheets; Usukohan supotto yosetsu tsugite no hippari sendan tsuyosa no suitei. 1st report. Teiko supotto yosetsu tsugite no tsuyosa

    Energy Technology Data Exchange (ETDEWEB)

    Kabasawa, M.; Funakawa, Y.; Ogawa, K. [NKK Corp., Tokyo (Japan); Tamura, M. [Kokan Keisoku Co. Ltd., Tokyo (Japan)

    1996-11-05

    Recently, use of thinner steel sheets was promoted with their higher strength for weight reduction of car body in the car industry, and also use of higher strength steel sheets was proceeded to improve its collision safety. Among such a condition, estimation of strength of the most fundamental single spot welding joint becomes important because body and parts strengths are mainly occupied by the strength of the welded joint. As relationships between shear strength and strength, thickness and nugget diameter of the steel sheets were investigated uptodate and a lot of empirical equations were obtained, a result obtained by numerical analysis was individual, and empirical equations obtained in conventional studies were narrow in their applied regions and could not be forecast for their application limits. In this study, for a joint obtained by a welding condition corresponding to A class of Japan Welding Society standard WES7301, as an object of low carbon steel sheet containing more than 0.03% of carbon widely used for the car body, an experimental equation to estimate tensile shear strength specified in JIS Z3136 from sheet thickness, mother material feature and nugget diameter was induced. 10 refs., 17 figs., 4 tabs.

  4. HYDRO-ABRASIVE JET CLEANING TECHNOLOGY OF STEEL SHEETS DESIGNED FOR LASER CUTTING

    Directory of Open Access Journals (Sweden)

    I. V. Kachanov

    2013-01-01

    Full Text Available Investigations executed by the BNTU “Shipbuilding and hydraulics” department have shown that rather efficient implementation of the requirements to the metal sheet surface designed for laser cutting can be achieved by using hydro-abrasive jet cleaning while applying water pump equipment with the range of pressure – 20–40 MPa. Type of working fluid plays a significant role for obtaining surface of the required quality. The conducted experiments have demonstrated that the efficient solution of the assigned problems can be ensured by using a working fluid containing bentonite clay, surface-active agent polyacrylamide, soda ash and the rest water.

  5. Numerical analysis of high strain rate failure of electro-magnetically loaded steel sheets

    Directory of Open Access Journals (Sweden)

    Erice Borja

    2015-01-01

    Full Text Available Electro-magnetic forces provide a potentially power full means in designing dynamic experiments with active control of the loading conditions. This article deals with the development of computational models to simulate the thermo-mechanical response of electro-magnetically loaded metallic structures. The model assumes linear electromagnetic constitutive equations and time-independent electric induction to estimate the Joule heating and the Lorentz forces. The latter are then taken into account when evaluating stress equilibrium. A thermo-visco-plastic model with Johnson-Cook type of temperature and strain rate dependence and combined Swift-Voce hardening is used to evaluate the material's thermo-mechanical response. As a first application, the model is used to analyse the effect of electro-magnetic loading on the ductility of advanced high strength steels.

  6. Tribology and Tool Wear of Hot Dip Galvanized Zinc Magnesium Alloys on Cold Rolled Steel Sheets

    Science.gov (United States)

    Raab, A. E.; Berger, E.; Freudenthaler, J.; Leomann, F.; Walch, C.

    2011-05-01

    Recently zinc based coatings on cold rolled steel with improved functionality in terms of forming and/or corrosion behaviour have been intensively investigated in the steel industry1,2,3. One of the most promising products are zinc magnesium alloys produced in hot dip galvanizing process. These coatings were already introduced in construction industry a few years ago1. With some modifications the improved properties of the coating are also interesting for automotive industry. In the present work the tribological potential of hot dip galvanized zinc magnesium coatings (HDG/ZM) produced at an industrial line under regular production, was studied in terms of sliding properties, adhesive and abrasive tool wear. First a short introduction into surface morphology of HDG/ZM will be given. For the tribological characterization of the material, which is the main topic of the contribution, different tests were performed on hot dip galvanised zinc magnesium material and results were compared with classic hot dip galvanized zinc coating (HDG/Z). The investigations are mainly based on the strip draw test which allows the determination of the friction coefficient directly by using a constant contact pressure. Deep drawing property was tested by forming model cups. The abrasive tool wear was tested using a standard test for material used in automotive industry. The adhesive tool wear was investigated by characterizing the coating material transferred to the tool in the strip draw test. All performed tests show an improved drawability of HDG/ZM compared to classical HDG/Z reference material. However the most promising difference between HDG/ZM and HDG/Z is that galling was found to be less for HDG/ZM than for HDG/Z. Therefore HDG/ZM is an interesting system not only with respect to corrosion protection but also in terms of tribology and provides clear advantages in formability.

  7. A comparative investigation of the efficacy of CO2 and high power diode lasers for the forming of EN3 mild steel sheets

    OpenAIRE

    Lawrence, Jonathan

    2002-01-01

    A comparative investigation of the effectiveness of a high power diode laser (HPDL) and a CO2 laser for the forming of thin section EN3 mild steel sheet has been conducted. The buckling mechanism was identified as the laser forming mechanism responsible for the induced bending. For both lasers it was found that the induced bending angles increased with an increasing number of irradiations and high laser powers, whilst decreasing as the traverse speed was increased. Also, it was apparent from ...

  8. Fiber laser welding of dual-phase galvanized sheet steel (DP590): traditional analysis and new quality assessment techniques

    Science.gov (United States)

    Miller, Stephanie; Pfeif, Erik; Kazakov, Andrei; Baumann, Esther; Dowell, Marla

    2016-03-01

    Laser welding has many advantages over traditional joining methods, yet remains underutilized. NIST has undertaken an ambitious initiative to improve predictions of weldability, reliability, and performance of laser welds. This study investigates butt welding of galvanized and ungalvanized dual-phase automotive sheet steels (DP 590) using a 10 kW commercial fiber laser system. Parameter development work, hardness profiles, microstructural characterization, and optical profilometry results are presented. Sound welding was accomplished in a laser power range of 2.0 kW to 4.5 kW and travel speed of 2000 mm/min to 5000 mm/min. Vickers hardness ranged from approximately 2 GPa to 4 GPa across the welds, with limited evidence of heat affected zone softening. Decreased hardness across the heat affected zone directly correlated to the appearance of ferrite. A technique was developed to non-destructively evaluate weld quality based on geometrical criteria. Weld face profilometry data were compared between light optical, metallographic sample, and frequency-modulated continuous-wave laser detection and ranging (FMCW LADAR) methods.

  9. Residual stress, micro-hardness and tensile properties of ANSI 304 stainless steel thick sheet by fiber laser welding

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, L. [School of Mechanical Engineering, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang 212013 (China); Lu, J.Z., E-mail: blueesky2005@163.com [School of Mechanical Engineering, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang 212013 (China); Luo, K.Y., E-mail: luokaiyu2012@gmail.com [School of Mechanical Engineering, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang 212013 (China); Feng, A.X. [School of Mechanical Engineering, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang 212013 (China); College of Mechanical Engineering, Wenzhou University, Wenzhou 325035 (China); Dai, F.Z.; Zhong, J.S.; Luo, M. [School of Mechanical Engineering, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang 212013 (China); Zhang, Y.K. [School of Mechanical Engineering, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang 212013 (China); School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)

    2013-01-20

    A fiber laser was chosen to weld the ANSI 304 stainless steel (ANSI 304 SS) sheets with a thickness of 5 mm. The effects of laser power, defocusing distance and welding speed on the weld appearances were investigated by the orthogonal test and the analyses on the appearances and properties of laser welds. Residual stress, micro-hardness and tensile properties of ANSI 304 SS welds were measured, and the cross section and surface morphologies were characterized by optical microscope (OM) compared with the two conventional laser (CO{sub 2}, Nd:YAG) welding methods. Results showed that ANSI 304 SS welds with good quality can be obtained if the appropriate fiber laser welding parameters were chosen. Tensile residual stresses of the fiber laser weld with the appropriate welding parameters were the lowest and micro-hardness and tensile properties were the highest among the three laser welding methods. In addition, the crystal solidification process induced by the fiber laser welding was schematically illustrated and systematically revealed.

  10. Investigation of the Hot-Stamping Process for Advanced High-Strength Steel Sheet by Numerical Simulation

    Science.gov (United States)

    Liu, H. S.; Xing, Z. W.; Bao, J.; Song, B. Y.

    2010-04-01

    Hot forming is a new way to manufacture complex-shaped components of advanced high-strength steel (AHSS) sheet with a minimum of spring-back. Numerical simulation is an effective way to examine the hot-forming process, particularly to determine thermal and thermo-mechanical characteristics and their dependencies on temperature, strain and strain rate. The flow behavior of the 22MnB5 AHSS is investigated through hot tensile tests. A 3D finite element (FE) model of hot-stamping process for the [InlineMediaObject not available: see fulltext.] shaped part is built under the ABAQUS/Explicit environment based on the solutions of several key problems, such as treatment of contact between blank and tools, determination of material characteristics and meshing, etc. Numerical simulation is carried out to investigate the influence of blank holder force (BHF) and die gap on the hot-forming process for the [InlineMediaObject not available: see fulltext.] shaped part. Numerical results show the FE model is effective in simulation of hot-forming process. Large BHF reduces the amount of spring-back and improves the contact of flange with tools while avoiding cracking of stamped part. Die gap has a considerable influence on the distribution of temperature on side walls; the larger the die gap, higher is the temperature on the sidewall of [InlineMediaObject not available: see fulltext.] shaped part.

  11. Experimental and numerical studies on formability of extra-deep drawing steel in incremental sheet metal forming

    Directory of Open Access Journals (Sweden)

    Suresh Kurra

    2014-04-01

    Full Text Available This paper focuses on the formability and thickness distribution in incremental sheet forming (ISF of extra-deep drawing steel (EDD. In ISF, the formability of the material is primarily measured by the maximum formable wall angle and maximum allowable thinning. The maximum wall angle is generally obtained by forming frustum of cones and square pyramids having different wall angles till fracture, which requires a large number of experiments. Therefore in the present study, a continuously varying wall angle conical frustum (VWACF was used to predict the maximum wall angle to minimize the number of experiments. VWACF is generated using circular, parabolic, elliptical and exponential generatrices. In order to get the maximum allowable thinning, the thickness of the formed geometry has been measured at various points along the depth. In addition, the thickness distribution has been computed theoretically based on the sine law and also using finite element code LS-DYNA. Theoretical and simulated thickness values have been compared with measured thickness values. It was found from the results that the finite element model was more accurate than theoretical model in predicting thickness distribution.

  12. Experimental investigations and statistical analysis of pulsed laser bending of AISI 304 stainless steel sheet

    Science.gov (United States)

    Maji, Kuntal; Pratihar, D. K.; Nath, A. K.

    2013-07-01

    This paper presents experimental investigations on pulsed laser bending of sheet metal and statistical analysis to study the effects of process parameters. Laser power, scan speed, spot diameter and pulsed duration were taken as input variables and bending angle was considered as the output. Response surface methodology was used for modeling and optimization of the pulsed laser bending process. The performance of the developed model was validated through the experiments. All the input variables were found to have significant influence on the bending angle. Bending angle increased with the increase of laser power and pulse duration and decreased with the increase of scan speed and spot diameter. The optimum process parameters for the maximum bending angle were also found and verified with experimental data. The effects of pulse frequency, pulse width and pulse energy on bending angle were also investigated through experiments. Bending angle was found to be the maximum for a certain value of pulse frequency. With the increase of pulse width, bending angle increased at constant laser power but decreased at constant pulse energy. Bending angle was seen to increase with the increase of spatial overlapping and decrease with the increase of gap at constant laser power, but it showed optimal values for both the cases at constant line energy. A comparative study between continuous and pulsed laser bending was carried out to study the process efficiency in terms of energy input and produced deformation.

  13. Evaluation of essential work of fracture in a dual phase high strength steel sheet; Evaluacion del trabajo esencial de fractura en chapa de un acero de alta resistencia de fase dual

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, D.; Perez, L. I.; Lara, A.; Casellas, D.; Prado, J. M.

    2013-03-01

    Fracture toughness of advanced high strength steels (AHSS), can be used to optimize crash behavior of structural components. However it cannot be readily measured in metal sheet because of the sheet thickness. In this work, the Essential Work of Fracture (EWF) methodology is proposed to evaluate the fracture toughness of metal sheets. It has been successfully applied in polymers films and some metal sheets. However, their information about the applicability of this methodology to AHSS is relatively scarce. In the present work the fracture toughness of a Dual Phase (strength of 800 MPa) and drawing steel sheets has been measured by means of the EWF. The results show that the test requirements are met and also show the clear influence of notch radii on the measured values, specially for the AHSS grade. Thus, the EWF is postulated as a methodology to evaluate the fracture toughness in AHSS sheets. (Author) 18 refs.

  14. Un nuevo sistema de diseño de embuticiones en láminas de acero para maximizar resistencia de losas compuestas A new system for designing embossments in steel sheets to increase composite slabs shear resistance

    Directory of Open Access Journals (Sweden)

    Melchor López Ávila

    2007-12-01

    Full Text Available Se presenta un resumen de algunos de los principales antecedentes históricos en el análisis de las losas compuestas con láminas metálicas colaborantes sometidas a flexión, así como de los principales métodos de diseño, instrumentación y ensayo aceptados por las distintas normas internacionales. Se analizan cada uno de los parámetros fundamentales que influencian el comportamiento estructural de las losas compuestas, y a partir del estudio numérico de estos se propone un método de optimización del sistema de embuticiones, implementado en hojas de cálculo, con el cual es posible estimar una resistencia a esfuerzos cortantes para las láminas de perfilado abierto y entregando los resultados de los parámetros más importantes, y que empleándolos en forma comparativa es posible determinar el sistema de embuticiones óptimo a incluir en una lámina de perfilado abierto. Aplicando el método propuesto obtuve un sistema de embuticiones tecnológicamente posible y con un coste mínimo de inversiones para una línea industrial de láminas de perfilado abierto.A summary is presented with the main historical background in the analysis of the composite slabs with steel sheets subjected to flexion, as well as of the main methods of design, instrumentation and tests accepted by different International Standards. They fundamental parameters that influence the structural behaviour of the composite slabs are analyzed, and with a numeric study an analytical optimization method of the embossments system, is proposed and implemented in a spread sheet is possible to estimate the shear resistance of open web sheets and by comparing them, is possible to determine the better embossments system to include in a open web sheet with such method. Applying the proposed method a technologically possible embossments system can be obtained with a minimum cost for an industrial line of open web sheets.

  15. Experimental investigation of the effect of the material damage induced in sheet metal forming process on the service performance of 22MnB5 steel

    Science.gov (United States)

    Zhuang, Weimin; Xie, Dongxuan; Chen, Yanhong

    2016-07-01

    The use of ultra-high strength steels through sheet metal forming process offers a practical solution to the lightweight design of vehicles. However, sheet metal forming process not only produces desirable changes in material properties but also causes material damage that may adversely influence the service performance of the material formed. Thus, an investigation is conducted to experimentally quantify such influence for a commonly used steel (the 22MnB5 steel) based on the hot and cold forming processes. For each process, a number of samples are used to conduct a uniaxial tensile test to simulate the forming process. After that, some of the samples are trimmed into a standard shape and then uniaxially extended until fracture to simulate the service stage. Finally, a microstructure test is conducted to analyze the microdefects of the remaining samples. Based on the results of the first two tests, the effect of material damage on the service performance of 22MnB5 steel is analyzed. It is found that the material damages of both the hot and cold forming processes cause reductions in the service performance, such as the failure strain, the ultimate stress, the capacity of energy absorption and the ratio of residual strain. The reductions are generally lower and non-linear in the former process but higher and linear in the latter process. Additionally, it is found from the microstructure analysis that the difference in the reductions of the service performance of 22MnB5 by the two forming processes is driven by the difference in the micro damage mechanisms of the two processes. The findings of this research provide a useful reference in terms of the selection of sheet metal forming processes and the determination of forming parameters for 22MnB5.

  16. Effect of the Die Temperature and Blank Thickness on the Formability of a Laser-Welded Blank of a Boron Steel Sheet with Removing Al-Si Coating Layer

    Directory of Open Access Journals (Sweden)

    M. S. Lee

    2014-05-01

    Full Text Available Reducing carbon emissions has been a major focus in the automobile industry to address various environmental issues. In particular, studies on parts comprised of high strength sheets and light car bodies are ongoing. Accordingly, this study examined the use of boron steel, which is commonly used in high strength sheets. Boron steel is a type of sheet used for hot stamping parts. Although it has high strength, the elongation is inferior, which reduces its crash energy absorption capacity. To solve this problem, two sheets of different thickness were welded so the thin sheet would absorb crash energy and the thick sheet would work as a support. Boron steel, however, may show weakening at the welding spot due to the Al-Si coating layer used to prevent oxidation from occurring during the welding process. Therefore, a certain part of the coating layer of a double-thickness boron steel sheet that is welded in the hot stamping process is removed through laser ablation, and the formability of the hot-work was examined.

  17. Effect of Die and Punch Radius on Springback of Stainless Steel Sheet Metal in the Air V-Die Bending Process

    Directory of Open Access Journals (Sweden)

    M.S. Buang

    2015-06-01

    Full Text Available This paper focuses on the effect of the die and punch radii on the springback in the air V-die free bending process of stainless steel sheet metal. The experiment was performed on sheet metal using various die and punch radius values while their springback behavior was observed. The design of experiment approach was used in these experiments using the full factorial and analysis of variance methods to identify whether or not the die and punch radii are significant input parameters in predicting springback. From the statistical analysis, it shows that the die and punch radius parameters are significant factors contributing to the springback effect in the V-die bending of stainless steel sheet metal at the significance level of 0.05 because their p-value is less than 0.05. The results from the experiments showed that springback is affected by the die and punch radius values in the air V-bending experiments. From this analysis, it can be concluded that the springback values can be decreased by decreasing the values of the die and punch radii. In the air V-die bending process, the punch radius is the most important factor to be considered. The experimental method agreed well with the design of experiment results.

  18. Effect of the determination method of the material parameters on the accuracy of the hole expansion simulation for cold rolled steel sheet

    Science.gov (United States)

    Nakano, Hayato; Hakoyama, Tomoyuki; Kuwabara, Toshihiko

    2017-10-01

    Hole expansion forming of a cold rolled steel sheet is investigated both experimentally and analytically to clarify the effects of material models on the predictive accuracy of finite element analyses (FEA). The multiaxial plastic deformation behavior of a cold rolled steel sheet with a thickness of 1.2 mm was measured using a servo-controlled multiaxial tube expansion testing machine for the range of strain from initial yield to fracture. Tubular specimens were fabricated from the sheet sample by roller bending and laser welding. Many linear stress paths in the first quadrant of stress space were applied to the tubular specimens to measure the contours of plastic work in stress space up to a reference plastic strain of 0.24 along with the directions of plastic strain rates. The anisotropic parameters and exponent of the Yld2000-2d yield function (Barlat et al., 2003) were optimized to approximate the contours of plastic work and the directions of plastic strain rates. The hole expansion forming simulations were performed using the different model identifications based on the Yld2000-2d yield function. It is concluded that the yield function best capturing both the plastic work contours and the directions of plastic strain rates leads to the most accurate predicted FEA.

  19. Hybrid friction diffusion bonding of 316L stainless steel tube-to-tube sheet joints for coil-wound heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Haneklaus, Nils; Cionea, Cristian; Reuven, Rony; Frazer, David; Hosemann, Peter; Peterson, Per F. [Dept of Nuclear Engineering, University of California, Berkeley (United States)

    2016-11-15

    Hybrid friction diffusion bonding (HFDB) is a solid-state bonding process first introduced by Helmholtz-Zentrum Geesthacht to join aluminum tube-to-tube sheet joints of Coil-wound heat exchangers (CWHE). This study describes how HFDB was successfully used to manufacture 316L test samples simulating tube-to-tube sheet joints of stainless steel CWHE for molten salt coolants as foreseen in several advanced nuclear- and thermal solar power plants. Engineering parameters of the test sample fabrication are presented and results from subsequent non-destructive vacuum decay leak testing and destructive tensile pull-out testing are discussed. The bonded areas of successfully fabricated samples as characterized by tube rupture during pull-out tensile testing, were further investigated using optical microscopy and scanning electron microscopy including electron backscatter diffraction.

  20. An inverse approach for the geometry prediction of sheet-metal parts with embossings made of high- and ultra-high strength steels

    Science.gov (United States)

    Stahl, J.; Tröber, P.; Feistle, M.; Golle, R.; Volk, W.

    2017-09-01

    Embossing or offsetting is a shear forming process closely related to fineblanking. It is mainly used for the manufacturing of functional geometry features like alignment pins on brake calipers or gears of seat adjustments. To achieve weight reduction, a trend towards the usage of high- and ultra-high-strength steels can be observed. Especially in embossing, the lack of knowledge for these grades evokes challenges in part design due to the higher springback and the different forming behaviour which greatly influence the characteristics of the formed geometry. Furthermore, Finite-Element simulations for geometry prediction are not yet able to achieve satisfying results due to the challenging material testing of the sheet-metal material. To address this problem, a novel method for the geometry prediction of sheet-metal parts with embossings made of high- and ultra-high-strength steels is proposed and demonstrated on the mild steels HSM 355 and HLB 22 as well as the high-strength steels HSM 700 HD and StrenX 700 MC plus. The method is based on the experimental identification of simple embossing geometries. Especially the die-roll was in the focus of interest, as it reduces the area available for functional features. A routine for the determination of the die-roll using the second derivative of the surface profile was implemented. The material model is subsequently calculated by an inverse algorithm. Furthermore, the dependency between the part’s geometry and the flow curve was investigated to reduce the calculation time. It is shown, that it is possible to determine a material model, which is capable of predicting the geometry of a part with an embossing for different materials and process parameters.

  1. 75 FR 6631 - Stainless Steel Sheet and Strip in Coils from Japan: Final Results of Antidumping Duty...

    Science.gov (United States)

    2010-02-10

    ... between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a... the scope of this order. This product is defined as a non-magnetic stainless steel manufactured to... order. These include stainless steel strip in coils used in the production of textile cutting tools (e.g...

  2. 76 FR 2332 - Stainless Steel Sheet and Strip in Coils From Mexico; Final Results of Antidumping Duty...

    Science.gov (United States)

    2011-01-13

    ... mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a coercivity of between 50 and... the order. This product is defined as a non-magnetic stainless steel manufactured to American Society... order. These include stainless steel strip in coils used in the production of textile cutting tools (e.g...

  3. 75 FR 62104 - Certain Stainless Steel Sheet and Strip in Coils From Germany, Japan, the Republic of Korea, and...

    Science.gov (United States)

    2010-10-07

    ... iron, in widths 228.6 mm or less, and a thickness between 0.127 and 1.270 mm. It exhibits magnetic... defined as a non-magnetic stainless steel manufactured to ] American Society of Testing and Materials... stainless steel strip in coils used in the production of textile cutting tools (e.g., carpet knives).\\5...

  4. 75 FR 76700 - Stainless Steel Sheet and Strip in Coils From Taiwan: Final Results of Antidumping Duty...

    Science.gov (United States)

    2010-12-09

    ... iron, in widths 228.6 mm or less, and a thickness between 0.127 and 1.270 mm. It exhibits magnetic... non-magnetic stainless steel manufactured to American Society of Testing and Materials specification... of textile cutting tools (e.g., carpet knives).\\4\\ This steel is similar to AISI grade 420 but...

  5. 75 FR 81221 - Stainless Steel Sheet and Strip in Coils From Mexico; Preliminary Results of the Five-Year...

    Science.gov (United States)

    2010-12-27

    ... between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a... the scope of the order. This product is defined as a non-magnetic stainless steel manufactured to... order. These include stainless steel strip in coils used in the production of textile cutting tools (e.g...

  6. 75 FR 6627 - Stainless Steel Sheet and Strip in Coils From Mexico; Final Results of Antidumping Duty...

    Science.gov (United States)

    2010-02-10

    ....127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a coercivity of... the scope of the order. This product is defined as a non-magnetic stainless steel manufactured to... order. These include stainless steel strip in coils used in the production of textile cutting tools (e.g...

  7. 75 FR 49467 - Stainless Steel Sheet and Strip in Coils From Taiwan: Preliminary Results and Rescission in Part...

    Science.gov (United States)

    2010-08-13

    ... or less, and a thickness between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and... also excluded from the scope of the order. This product is defined as a non-magnetic stainless steel... include stainless steel strip in coils used in the production of textile cutting tools (e.g., carpet...

  8. 76 FR 49450 - Stainless Steel Sheet and Strip in Coils From Germany, Italy, and Mexico: Revocation of...

    Science.gov (United States)

    2011-08-10

    ... iron, in widths 228.6 mm or less, and a thickness between 0.127 and 1.270 mm. It exhibits magnetic... defined as a non-magnetic stainless steel manufactured to American Society of Testing and Materials (ASTM... the production of textile cutting tools (e.g., carpet knives).\\7\\ This steel is similar to AISI grade...

  9. 75 FR 62101 - Stainless Steel Sheet and Strip in Coils From the Republic of Korea: Final Results of Expedited...

    Science.gov (United States)

    2010-10-07

    ... between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a... the scope of the order. This product is defined as a non-magnetic stainless steel manufactured to... order. These include stainless steel strip in coils used in the production of textile cutting tools (e.g...

  10. 75 FR 5947 - Stainless Steel Sheet and Strip in Coils from Taiwan: Final Results and Rescission in Part of...

    Science.gov (United States)

    2010-02-05

    ... between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a... the scope of the order. This product is defined as a non-magnetic stainless steel manufactured to... include stainless steel strip in coils used in the production of textile cutting tools (e.g., carpet...

  11. The Work Softening by Deformation-Induced Disordering and Cold Rolling of 6.5 wt pct Si Steel Thin Sheets

    Science.gov (United States)

    Wang, Xianglong; Li, Haoze; Zhang, Weina; Liu, Zhenyu; Wang, Guodong; Luo, Zhonghan; Zhang, Fengquan

    2016-09-01

    As-cast strip of 6.5 wt pct Si steel was fabricated by twin-roll strip casting. After hot rolling at 1323 K (1050 °C), thin sheets with the thickness of 0.35 mm were produced by warm rolling at 373 K (100 °C) with rolling reductions of 15, 25, 35, 45, 55, and 65 pct. Influence of warm rolling reduction on ductility was investigated by room temperature bending test. The measurement of macro-hardness showed that "work softening" could begin when the warm rolling reduction exceeded 35 pct. The room temperature ductility of the thin sheets gradually increased with the increase of warm rolling reductions, and the plastic deformation during bending began to form when the warm rolling reduction was greater than 45 pct, the 65 pct rolled thin sheet exhibited the maximum plastic deformation of about 0.6 pct during bending at room temperature, with a few small dimples having been observed on the fracture surfaces. B2-ordered domains were formed in the 15, 25, 35, 45, and 55 pct rolled specimens, and their average size decreased with the increase of warm rolling reductions. By contrast, no B2-ordered domain could be found in the 65 pct rolled specimen. It had been observed that large-ordered domains could be split into several small parts by the slip of partial super-dislocations during warm rolling, which led to significant decrease of the order degree to cause the phenomenon of deformation-induced disordering. On the basis of these results, cold rolling schedule was developed to successfully fabricate 0.25-mm-thick sheets with good surface qualities and magnetic properties from warm rolled sheets.

  12. The Bending Behaviour of a ‘Reversed’ Profiled Steel Sheet Dry Board (PSSDB Panel for Application in a Roofing System

    Directory of Open Access Journals (Sweden)

    Hanizam Awang

    2009-11-01

    Full Text Available Finite element modelling and experimental study of the structural behaviour involving the stiffness and strength of an innovative composite panel system known as the Profiled Steel Sheet Dry Board (PSSDB system, to be applied as roofing units in buildings, is investigated in this paper. The system consists of profiled steel sheeting connected to dry board by self-drilling and self-tapping screws. This study considered the behaviour of the PSSDB panel under an out-of plane uniform load to understand the behaviour of the PSSDB panel when it is positioned in a ‘reversed’ position in order to make it more practical and applicable. In addition, the effect of introducing side timber strips along the edge side of the panel system is also studied. It is found that the timber strips increased the stiffness value from 57.6 kNm2 m–1 to 78.2 kNm2 m–1, i.e., an increase of 35.8% compared to panels without timber jointing strips. In fact, the maximum load that can be sustained by the connected panels was increased from 3.47 kN m–1 to 6 kN m–1. The finite element model developed has shown accuracy within 5% to 11% compared to experimental results in predicting the deflection of the PSSDB panel.

  13. RESULTS OF CALCULATION-EXPERIMENTAL INVESTIGATIONS OF ELECTRO-THERMAL RESISTIBILITY OF SHEET STEEL SAMPLES TO ACTION OF RATIONED COMPONENTS OF PULSED CURRENT OF ARTIFICIAL LIGHTING

    Directory of Open Access Journals (Sweden)

    M.I. Baranov

    2016-06-01

    Full Text Available Purpose. Calculation and experimental researches of the electro-thermal resistibility of the steel sheet samples to action standard pulse current components of the artificial lightning with amplitude-time parameters (ATP, corresponded the requirements of normative documents of USA for SAE ARP 5412 & SAE ARP 5416. Methodology. Electrophysics bases of technique of high tensions and large impulsive currents (LIC, and also scientific and technical bases of planning of devices of high-voltage impulsive technique and measuring in them LIC. Сurrent amplitude ImA=±200 kA (with a tolerance of ±10 %; current action integral JA=2∙106 A2•s (with a tolerance of ±20 %; time, corresponding to the amplitude of the current ImA, tmA≤50 microseconds; the duration of the current flow τpA≤500 microseconds. Results. The results of the evaluation of the calculated and experimental studies of electro-thermal resistance of the samples of plates measuring 0,5 m  0,5 m stainless steel 1 mm thickness to the action on them artificial lightning impulse currents with rationed ATP on the requirements of normative documents of USA for SAE ARP 5412 & SAE ARP 5416. A pulse A- component have a first amplitude 192 kA, the corresponding time of 34 μs, and the duration aperiodic component amplitude 804 A, corresponding to the time 9 ms. It has been shown that the long C- component current of artificial lightning can lead to keyhole these samples. The diameter of the holes in this thin steel sheet, which is formed during the flow of current C- components can reach 15 mm. The results of calculation and experiment agree within 28 %. Originality. For the first time in world practice on the generator large pulsed currents experimental studies of resistibility of sheet steel samples to the action of artificial lightning currents with critical parameters. Practical value. Using the results obtained in the practice of lightning protection will significantly improve the

  14. 75 FR 47780 - Stainless Steel Sheet and Strip in Coils From Mexico; Preliminary Results of Antidumping Duty...

    Science.gov (United States)

    2010-08-09

    ... a thickness between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000... is also excluded from the scope of the order. This product is defined as a non-magnetic stainless... textile cutting tools (e.g., carpet knives).\\7\\ This steel is similar to ASTM grade 440F, but containing...

  15. 75 FR 81214 - Stainless Steel Sheet and Strip in Coils From Italy: Preliminary Results of the Full Second Five...

    Science.gov (United States)

    2010-12-27

    ... or less, and a thickness between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and... is also excluded from the scope of the order. This product is defined as a non-magnetic stainless... scope of the order. These include stainless steel strip in coils used in the production of textile...

  16. Reduction Kinetics of Wüstite Scale on Pure Iron and Steel Sheets in Ar and H2 Gas Mixture

    Science.gov (United States)

    Mao, Weichen; Sloof, Willem G.

    2017-10-01

    A dense and closed Wüstite scale is formed on pure iron and Mn alloyed steel after oxidation in Ar + 33 vol pct CO2 + 17 vol pct CO gas mixture. Reducing the Wüstite scale in Ar + H2 gas mixture forms a dense and uniform iron layer on top of the remaining Wüstite scale, which separates the unreduced scale from the gas mixture. The reduction of Wüstite is controlled by the bulk diffusion of dissolved oxygen in the formed iron layer and follows parabolic growth rate law. The reduction kinetics of Wüstite formed on pure iron and on Mn alloyed steel are the same. The parabolic rate constant of Wüstite reduction obeys an Arrhenius relation with an activation energy of 104 kJ/mol if the formed iron layer is in the ferrite phase. However, at 1223 K (950 °C) the parabolic rate constant of Wüstite reduction drops due to the phase transformation of the iron layer from ferrite to austenite. The effect of oxygen partial pressure on the parabolic rate constant of Wüstite reduction is negligible when reducing in a gas mixture with a dew point below 283 K (10 °C). During oxidation of the Mn alloyed steel, Mn is dissolved in the Wüstite scale. Subsequently, during reduction of the Wüstite layer, Mn diffuses into the unreduced Wüstite. Ultimately, an oxide-free iron layer is obtained at the surface of the Mn alloyed steel, which is beneficial for coating application.

  17. Form removal aspects on the waviness parameters for steel sheet in automotive applications : fourier filtering versus polynomial regression

    OpenAIRE

    Vermeulen, Michel; Balabane, Mikhael; Mallé, Celine

    2017-01-01

    Premium car makers attach great importance to the visual appearance of the painted car skin as an indication of product quality. The “orange peel” phenomenon constitutes a major problem here. It is not only depending on the paint’s chemical composition and application method, but also on possible waviness components in the sheet substrate. Therefore one is searching hard for a valuable waviness parameter to quantify the substrate’s fitness for purpose. A technically emerging problem is how to...

  18. ANÁLISE TÉRMICA DE EDIFICAÇÕES CONSTRUÍDAS EM LIGHT STEEL FRAME

    Directory of Open Access Journals (Sweden)

    Beatriz Costa Mendonça

    2016-11-01

    Full Text Available Este estudo analisará o desempenho térmico em edificações construídas em light steel frame, perfis de aços leves que apresentam excelentes vantagens, inclusive para o meio ambiente. Quanto melhor a eficiência energética de uma residência menor é o gasto com energia elétrica e menor é a produção da energia. Será usado o software WUFI para analisar as temperaturas internas da habitação. Com o software pode-se testar diversos materiais e escolher o que apresentar melhor custo x benefício para o meio ambiente, o construtor e o habitante da residência. Assim pode-se ter uma residência onde tanto o sistema construtivo quanto a eficiência energética funcionam em prol do meio ambiente e também atendem a norma de desempenho NBR 15575.

  19. Mechanical Behavior of Lithium-Ion Batteries and Fatigue Behavior of Ultrasonic Weld-Bonded Lap-Shear Specimens of Dissimilar Magnesium and Steel Sheets

    Science.gov (United States)

    Lai, Wei-Jen

    The mechanical behaviors of LiFePO4 battery cell and module specimens under in-plane constrained compression were investigated for simulations of battery cells, modules and packs under crush conditions. The experimental stress-strain curves were correlated to the deformation patterns of battery cell and module specimens. Analytical solutions were developed to estimate the buckling stresses and to provide a theoretical basis for future design of representative volume element cell and module specimens. A physical kinematics model for formation of kinks and shear bands in battery cells was developed to explain the deformation mechanism for layered battery cells under in-plane constrained compression. A small-scale module constrained punch indentation test was also conducted to benchmark the computational results. The computational results indicate that macro homogenized material models can be used to simulate battery modules under crush conditions. Fatigue behavior and failure modes of ultrasonic spot welds in lap-shear specimens of magnesium and steel sheets with and without adhesive were investigated. For ultrasonic spot welded lap-shear specimens, the failure mode changes from the partial nugget pullout mode under low-cycle loading conditions to the kinked crack failure mode under high-cycle loading conditions. For adhesive-bonded and weld-bonded lap-shear specimens, the test results show the near interface cohesive failure mode and the kinked crack failure mode under low-cycle and high-cycle loading conditions, respectively. Next, the analytical effective stress intensity factor solutions for main cracks in lap-shear specimens of three dissimilar sheets under plane strain conditions were developed and the solutions agreed well with the computational results. The analytical effective stress intensity factor solutions for kinked cracks were compared with the computational results at small kink lengths. The results indicate that the computational results approach to

  20. Aplicación del rayo láser de CO2 para soldar laminas de acero bajo carbono // Application of the ray laser of CO2 to weld sheets of steel low carbon

    Directory of Open Access Journals (Sweden)

    Enrique J. Martínez D

    1999-07-01

    very thin sheets is facilitated, that which difficultly is achieved withthe processes common of welding. This technique also presents the advantage that easily you can automate, producing weldings ofhigh precision with low contamination.The study consists on carrying out an investigation on the process of welding of thin sheets using a laser of CO2 of low power incontinuous way, focusing the laser with a lens of ZnSe and using industrial argon to control the atmosphere around the treated regionand to avoid the oxidation. To carry out the process, you design a device for ' to displace the sample at 45o with regard to thetrajectory of the ray laser in precise form; the welding was carried out to it collides and without material contribution.The work was carried out on sheets of steel of low coal of caliber 24 and 26. The welded samples were subjected to: tractionrehearsal, visual analysis, analysis metalográfico and microdureza tests. The obtained results show that it can be carried out theprocess easily, by means of the control of the most important variables, in such a way that once established, the operator doesn't needa great experience in the handling of this technique to carry out the process with high quality. The carried out analyses confirm thatby means of this technique it is possible to obtain uniform welding cords, with good mechanical properties.Key words: Welding, laser.

  1. Grey–Taguchi method to optimize the percent zinc coating balances edge joints for galvanized steel sheets using metal inert gas pulse brazing process

    Directory of Open Access Journals (Sweden)

    Khasempong Songsorn

    2016-06-01

    Full Text Available The objective of this work was to optimize the percent zinc coating balances edge joints of galvanized steel sheets using the metal inert gas pulse brazing process. The Taguchi method and grey relational analysis were used to determine the relationship between the metal inert gas pulse brazing process parameters and percent zinc coating balances edge joints. The metal inert gas pulse brazing process parameters used in this study included wire feed speeds, arc voltages, travel speed, peak currents, and pulse frequency. The characteristics of metal inert gas pulse brazing process that were considered to find response were percent zinc coating balances edge joints on the upper edge joint (PZBEJ1, the lower edge joint (PZBEJ2, and the back sides of the edge joint (PZBEJ3. Analysis of variance was performed to determine the impact of an individual process parameter on the quality parameters. The results showed that the optimal parameters in which grey relational grade increases at the highest level were wire feed speeds at 3.25 m/min, arc voltages at 16 V, travel speeds at 0.9 m/min, peak currents at 425 A, and pulse frequency at 35 Hz. These parameters gave a 74.90% higher response value than those of the initial parameters of metal inert gas pulse brazing process.

  2. Study on mechanical behavior of the deep embeded steel sheet pile cellular bulkhead. Neire no fukai hagane yaita cell shiki gogan no rikigaku teki kyodo ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Higashigawa, T.; Achiwa, F. (The Chubu Electric Power Co. Inc., Nagoya (Japan)); Matsuo, M. (Nagoya Univ., Nagoya (Japan). Faculty of Engineering); Sunami, S. (Nikken Sekkei, Osaka (Japan))

    1991-09-20

    At the Hekinan coal-burning thermal power station of Chubu Electric Power Company, there is a plan to construct its ash dump by closing the neighboring sea area with bulkheads. This bulkhead is deeply embeded steel sheet piles to be struck into a soft clay layer. Since it is necessary to improve the ground in a wide area for stabilization of soft clay, the specifications as well as the scope of improvement of the basic design plan were noticed, a qualitative study of the bulkhead was done by a numerical analysis aiming at realization of a rational and economical bulkhead and an execution plan which modified the above was prepared. In this execution plan, the reduction as much as about 9% became possible for the construction cost of about 1km long bulkheads. In order to demonstrate the adequacy of this execution plan, loading tests were conducted on full-size cellular bulkheads corresponding to the basic plan as well as the execution plan. As a result, the tested values agreed very well with the analytical results and upon comparison between them, the displacement at the tip of the cellular bulkhead and other measured values showed no meaningful difference, thereby it was confirmed that the execution plan had the same level of stability as the basic plan. 5 refs., 26 figs., 5 tabs.

  3. Development of prepainted steel sheets having excellent formability, stain resistance, and hardness by control of orientation behavior of melamine-formaldehyde resin in the paint film; Kakosei, taiosensei, kodo tokusei ni sugureru precoat koban no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kanai, H.; Oka, J.; Tsutsumi, M. [Nippon Steel Corp., Tokyo (Japan)

    1994-08-01

    In the present research, the prepainted steel sheet was developed which was coated with melamine-formaldehyde resin (Rm) excelling in stain resistance and hardness. Study was made under various Res/Rm blending conditions by selecting, as a test sample, three types of polyester resin (Res), four types of Rm and two types of catalyst. The superficial structure of coated layer was analyzed by X-ray photoelectron spectroscopy. An Rm-enriched layer could be formed by combining Res of a low hydroxyl value and a strongly acidic catalyst blocked with amine. In such a formation mechanism, catalytic activity directly below the coated surface and self-condensation of Rm were observed during the backing. There exists a positive correlativity between the stain resistance and superficial Rm concentration of blended Res/Rm system. The stain resistance is judged dependent upon the self-condensation. The precoated steel sheet which excels in formability even at a room temperature of 20{degree}C was commercialized and is being sold. As compared with the conventional high-grade products, the present steel sheet is lustrous even through a 24h submergence in 5% NaOH and H2SO4. A stain resistance test in magic ink also gave a good result. 5 refs., 8 figs., 4 tabs.

  4. Development of prepainted steel sheets having excellent formability, stain resistance and hardness by control of orientation behavior of melamine-formaldehyde resin in the paint film. Tomakuchu no melamine jushi haiko seigyo gijutsu ni yoru kakosei taiosensei kodo ni sugureta precoat koban no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kanai, H.; Oka, J.; Tsutsumi, M. (Nippon Steel Corp., Tokyo (Japan))

    1994-06-20

    Since most prepainted steel sheets are usually formed for further working, these materials must have high workability (paint film with high deformation resistance). In addition, hardness and stain resistance inherent to steel sheets must be maintained. High workability is difficult to provide for steel sheets with high hardness and stain resistance. This is one of the reasons why the applications of prepainted steel sheets have been limited. This paper describes the study of the relationships between the paint film structure and the nature of polyester (PE) and melamine-formaldehyde (MM) resin. As a result of the study, the technology of control of orientation behavior of MM in paint film was established, and, with the technology, new prepainted steel sheets were developed to solve the problem above. In this case, formability (almost decided by the elongation percentage) depends on soft PE, while hardness and stain resistance (closely related to the paint film surface structure) depend on hard MM. The compounding ratio of the material was designed so that the MM bridge formation density is higher on the surface of paint film and lower inside the paint film, taking into account the reaction mechanism. Thus, the technology of densifying the MM surface has provided the excellent and unique performance for prepainted steel sheets. 5 refs., 6 figs., 4 tabs.

  5. 76 FR 25668 - Stainless Steel Sheet and Strip in Coils From Mexico: Final Results of the Five-Year (“Sunset...

    Science.gov (United States)

    2011-05-05

    ... magnetic remanence between 9,000 and 12,000 gauss, and a coercivity of between 50 and 300 oersteds. This... product is defined as a non-magnetic stainless steel manufactured to American Society of Testing and... stainless steel strip in coils used in the production of textile cutting tools (e.g., carpet knives).\\5...

  6. 76 FR 25670 - Stainless Steel Sheet and Strip in Coils From Italy: Final Results of the Full Five-Year (“Sunset...

    Science.gov (United States)

    2011-05-05

    ... between 0.127 and 1.270 mm. It exhibits magnetic remanence between 9,000 and 12,000 gauss, and a... the scope of the order. This product is defined as a non-magnetic stainless steel manufactured to... order. These include stainless steel strip in coils used in the production of textile cutting tools (e.g...

  7. DEVELOPMENT OF CORES FOR MINI MOTORS FROM LAMINATED SHEETS OF ELECTRIC STEEL ABNT (Brazilian Association of Technical Standards 35F 420M WITH THERMAL TREATMENT

    Directory of Open Access Journals (Sweden)

    Halston Mozetic

    2016-06-01

    Full Text Available The purposes of this paper were to study the thermal treatment of Fe-Si sheet, as well as the sheet cutting concerning the topology of a mini stepper motor and mini motor simulation using finite element software. The research consisted of the execution of an "Inductive Reheating" thermal treatment of Iron Silicon sheets, NM71-2000/35F 420M with GNO (Grain Non Oriented, and 0.35mm width. The new technique has the benefit of minimizing magnetic losses produced by the cut on the edge of electric sheets. To carry out the process, the system includes a furnace, an induction coil, and a power supply that, when activated in a controlled way, causes relevant changes to the crystalline structure of the material. Related to the cut of the sheets, the topology of a three phase mini stepper motor was considered. The sheets were initially cut using the geometry of the rotor and stator cores. Firstly, a die cutting process was used and later a wire electroerosion cutting process was employed, which provided parts with excellent finishing. Finally, the mini motor was simulated using the finite element software FEMM 4.2 in order to analyze the airgap flow and torque development of the axis end, in comparison to a solid block of the same material (Fe-Si

  8. Diffusion brazing nickel-plated stainless steel

    Science.gov (United States)

    Beuyukian, C. S.; Mitchell, M. J.

    1976-01-01

    To bond parts, sandwich assembly is made up of aluminum core, aluminum face sheet with brazing alloy interface, and nickel plated stainless steel part. Sandwich is placed between bottom and top glide sheet that is placed in stainless steel retort where assembly is bonded at 580 C.

  9. On High-Temperature Materials: A Case on Creep and Oxidation of a Fully Austenitic Heat-Resistant Superalloy Stainless Steel Sheet

    Directory of Open Access Journals (Sweden)

    A. Kanni Raj

    2013-01-01

    Full Text Available The creep behavior of AISI 310S stainless steel taken from SAIL’s Salem stainless steel plant has been investigated by constant load tensile creep test at the temperatures of 973, 1023, and 1073 K and loads of 66.6, 74.8, 86.6, and 94.8 MPa. It exhibits steady-state creep behavior in most test conditions. The double logarithm plot of rupture life and applied stress yielded straight lines at all the three test temperatures indicating that power-law creep due to dislocation climb is the operating mechanism of creep deformation. Linear relationship was obtained for plots of logarithm of rupture life against inverse temperature obeying Arrhenius type of temperature dependence with activation energy of 340 kJ/mol. The stress-rupture data yielded a master curve of Larson-Miller parameter. The plot of Monkman-Grant relationship is typical indicating that rupture is controlled by growth of grain boundary cavities. The metallographic examination of crept samples revealed formation of grain boundary voids and cracks leading to intergranular creep fracture. Deformation twins and carbide precipitates were also observed. Oxidation tests were also carried out isothermally at 973 K, 1023 K, and 1073 K in dry air. The plots of mass gain versus square root time were linear at all the three test temperatures obeying parabolic kinetics of oxidation. It was found that scales are well adherent to the substrate. The plot of parabolic rate constant and inverse temperature was linear giving an activation energy value of 210 kJ/mol. The metallographic examination of an oxidized sample reveals duplex types of scales. Finally, rupture properties are compared with that of AISI 600 iron-based superalloy and oxidation weight gain analysis with surface nanocrystalline AISI 310S stainless steel to analyze quantitatively its behavior.

  10. Sheet music

    OpenAIRE

    Martin, Gregory

    2016-01-01

    Sheet music is a handwritten or printed form of music notation that uses modern musical symbols. Like its analogs – books, pamphlets, etc. – the medium of sheet music typically is paper (or, in earlier times, parchment), although the access to musical notation in recent years also includes presentation on computer screens. Use of the term "sheet" is intended to differentiate written music from an audio presentation, as in a sound recording, broadcast or live performance, which may involve vid...

  11. Soldadura de aceros dual phase en chapa fina: GMAW, PAW y RSW Welding of dual phase steel sheet: GMAW, PAW and RSW

    Directory of Open Access Journals (Sweden)

    Hernán Svoboda

    2011-06-01

    Full Text Available Los aceros Dual Phase (DP han encontrado recientemente una fuerte aplicación en elementos estructurales en la industria automotriz, debido a la necesidad de disminuir peso. La soldadura de estos materiales cobra particular importancia considerando su aplicación estructural y los procesos relacionados en su fabricación. En particular la soldadura de resistencia por punto (RSW y semiautomática con alambre macizo y protección gaseosa (GMAW son ampliamente utilizados en la industria automotriz. El proceso de soldadura por plasma (PAW se caracteriza, entre los procesos de soldadura por arco, por ser el de mayor densidad de energía, presentando particular interés en aplicaciones de la industria automotriz (tailor welded blanks. El objetivo del presente trabajo fue estudiar la evolución microestructural y las propiedades de aceros DP soldados mediante los procesos RSW, GMAW y PAW. A este fin, se soldaron cuatro grados de aceros DP con resistencias mecánicas de 550, 700 y 850 MPa en espesores de 1 y 1,3 mm mediante los mencionados procesos. Se caracterizaron las microestructuras y se determinaron las propiedades mecánicas de las uniones soldadas para cada caso. Para los tres procesos se obtuvieron uniones soldadas de calidad satisfactoria. Se observó para todas las soldaduras, que en la ZAC se produce una disminución de la dureza por debajo del valor del material base, relacionada a la descomposición de la fase martensítica. Las soladuras por arco fueron las más afectadas.Dual Phase steels (DP have been used recently as an interesting option for structural elements, specialy in automotive industry, due to weight reduce requirements. Welding of these materials becomes particularly important considering their application as structural elements and the related manufacturing methods. In particular resistance spot welding (RSW and gas metal arc welding (GMAW are widely used in the automotive manufacturing. The plasma arc welding (PAW has the

  12. Soldering sheets using soft solders

    Directory of Open Access Journals (Sweden)

    Milan Brožek

    2013-01-01

    Full Text Available The paper contains strength tests results of joints soldered using lead and leadless soft solders. For tests lead solders types Pb60Sn40 and Sn60Pb40 and leadless soft solders types Sn95.5Ag3.8Cu0.7 and Sn96Ag4 were used. As basic materials steel sheet, zinc-coated steel sheet, copper sheet and brass sheet 100 x 20 x 1 mm was the test samples size. Always two sheets were cleaned and jointed together. For heating the propane-butane + air flame was used. Then the tested assemblies were loaded using the universal tensile-strength testing machine till to failure. At the tests the force needed for assemblies failure and failure type (in soldered joint, in basic material were recorded. From measured data the solder strength was calculated. From the experiment results it follows that from the point of view of the soldered joints strength as well of the solder strength relatively small differences were found. At the same time it is evident that the joint strength and solder strength depend on soldered material type and on soldered joint lapping length. On the basis of carried out experiments it can be stated that the substitution of lead solders by leadless solders is possible without risk of soldered joints strength decrease.

  13. THE ACCOUNT OF OPTIONS SHEET OF WALLS PROFILE LARSEN IN THE DESIGN OF EXCAVATIONS SUPPORTING

    Directory of Open Access Journals (Sweden)

    Rashid A. Mangushev

    2017-12-01

    Full Text Available Bending stiffness and strength of steel sheet retaining walls is strongly dependent on shear resistance of pile interlocks. This fact, usually, is not taken into account in domestic practice of design and construction of sheet walls

  14. 1998 Annual Study Report. Standardization of corrosion resistance testing/evaluation methods for coated steel sheets; 1998 nendo seika hokokusho. Hyomen shori koban no taishokusei shiken hyoka hoho no hyojunka

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In order to develop the evaluation methods for reappearing corrosion characteristics of coated steel sheets in a short time, acid rain composition and artificial acid rain composition for the accelerated test were studied, and the cyclic corrosion tests were conducted. The literature survey shows that the main ionic species present in acid rain are Ca{sup 2+}, Mg{sup 2+}, Na{sup +}, K{sup +}, NH{sub 4}{sup +}, SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, and Cl{sup -}, of which the acid rain components are SO{sub 4}{sup 2-} and NO{sub 3}{sup -}, their equivalent ratio (NO{sub 3}{sup -}/ SO{sub 4}{sup 2-}) in the Far Eastern area being 0.2 to 0.3. Therefore, the solution specified by ASTM 1141 is diluted 30 times with water to prepare the base solution for the accelerated tests, where its acidity is adjusted with a mixed acid of NO{sub 3}{sup -}/ SO{sub 4}{sup 2-} = 0.2 to 0.3 (pH: 3.0 to 4.0). Two sets of preliminary cyclic corrosion tests were conducted, one involving acid rain spraying, drying and humidification in this order, and the other acid rain spraying, humidification and drying. Analysis of the test data indicates that difference between these test cycles in corrosion rate is within a deviation range caused by different testing tools. Therefore, the former condition is adopted as the basis for the accelerated tests, because of its smaller deviation caused by different testing tools. (NEDO)

  15. A mathematical approach based on finite differences method for analyzing the temperature field in arc welding of stainless steel thin sheets; Desarrollo de un modelo matematico de diferencias finitas para el analisis del campo de temperaturas en la soldadura por arco de chapas finas de acero inoxidable

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Conesa, E.J.; Estrems, M.; Miguel, V.

    2010-07-01

    This work develops a finite difference method to evaluate the temperature field in the heat affected zone in butt welding applied to AISI 304 stainless steel thin sheet by GTAW process. A computer program has been developed and implemented by Visual Basic for Applications (VBA) in MS-Excel spreadsheet. The results that are obtained using the numerical application foresee the thermal behaviour of arc welding processes. An experimental methodology has been developed to validate the mathematical model that allows to measure the temperature in several points close to the weld bead. The methodology is applied to a stainless steel sheet with a thickness lower than 3 mm, although may be used for other steels and welding processes as MIG/MAG and SMAW. The data which has been obtained from the experimental procedure have been used to validate the results that have been calculated by the finite differences numerical method. The mathematical model adjustment has been carried out taking into account the experimental results. The differences found between the experimental and theoretical approaches are due to the convection and radiation heat losses, which have not been considered in the simulation model.With this simple model, the designer will be able to calculate the thermal cycles that take place in the process as well as to predict the temperature field in the proximity of the weld bead. (Author). 18 refs.

  16. Application of Hydroforming Process in Sheet Metal Formation

    OpenAIRE

    GRIZELJ, Branko; CUMIN, Josip; ERGIĆ, Todor

    2009-01-01

    This article deals with the theory and application of a hydroforming process. Nowadays automobile manufacturers use high strength sheet metal plates. This high strength steel sheet metal plates are strain hardened in the process of metal forming. With the use of high strength steel, cars are made lightweight, which is intended for low fuel consumption because of high energy prices. Some examples of application of a hydroforming process are simulated with FEM.

  17. Development of [l brace]100[r brace] texture in silicon steel sheets by isothermal austenite[yields]ferrite transformations and its mechanism. Keiso kohan ni okeru toon [gamma][yields][alpha] hentai ni yoru [l brace]100[r brace] shugo soshiki no keisei to sono kiko

    Energy Technology Data Exchange (ETDEWEB)

    Tomida, T. (Sumitomo Metal Industries Ltd., Osaka (Japan). Advanced Technology Research Lab.); Tanaka, T. (Sumitomo Metal Industries Ltd., Osaka (Japan). Iron and Steel Research Lab.)

    1993-12-01

    The texture in silicon steel sheets has been studied during this half of century and the methods for forming the textures suitable as the soft-magnetic materials of [l brace]110[r brace][l angle]001[r angle] as well as [l brace]100[r brace][l angle]001[r angle] have been found. However, few researches has been carried out on the silicon steel using positively the innate properties of the steel such as the transformation between the austenite ([gamma]) and [alpha]-ferrite and the recrystallization in the coexisting area of [alpha]/[gamma] duplex. In this study, the isothermal [alpha][yields][gamma] transformation during the process of vacuum-annealing and decarburizing-annealing of 2% silicon steel containing carbon and Mn and the texture formation accompanied therewith are examined. The conclusions are as follows. The isothermal [alpha][yields][gamma] transformation occurs in the layer just below the surface and the structure of the surface becomes the single phase of [alpha]-ferrite in the vacuum of 10[sup -3]Pa and the temperature is kept constant within the range of [alpha]/[gamma] duplex temperature or [gamma]-phase temperature as from 850 to 1050 centigrade. This surface structure develops to the strong [l brace]100[r brace] texture. 12 refs., 8 figs., 2 tabs.

  18. The stretch zone of automotive steel sheets

    Indian Academy of Sciences (India)

    Author Affiliations. Ľ Ambriško1 L Pešek2. Institute of Structural Engineering, Faculty of Civil Engineering, Technical University of Košice, Vysokoškolská 4, 042 00 Košice, Slovak Republic; Department of Materials Science, Faculty of Metallurgy, Technical University of Košice, Letná 9, 042 00 Košice, Slovak Republic ...

  19. Le corps numérique des données The Digital Body of Data: the Transfer of Artefact Fact Sheets from the Museum of Man to the Musée du quai Branly

    Directory of Open Access Journals (Sweden)

    Tiziana Nicoletta Beltrame

    2012-05-01

    Full Text Available Le transfert des collections extra-européennes du musée de l’Homme au musée du quai Branly implique le déplacement des informations documentaires sur les objets. Des différentes fiches en papier (de collection ou d’inventaire, descriptive de l’objet, méthodique créées et classées au sein des départements du musée de l’Homme, on passe à la fiche informatique « TMS objets » au musée du quai Branly. L’information ne change pas simplement de place et de matière, elle est reconfigurée dans de nouvelles articulations du savoir sur les collections. L’inventaire muséal est ici conçu comme le système qui matérialise un savoir structuré. Pour pouvoir analyser ce système, il faut mettre en relation les propriétés des documents et les modalités de leur classement dans un espace créé ad hoc. La matérialité des supports, les multiples possibilités de rangements et de création de liens (la mise en relations entre rubriques de la fiche informatique agissent sur le contenu des données et ouvrent ainsi de nouvelles voies pour la construction du savoir.The transfer of extra-European collections from the Museum of Man to the Musée du quai Branly involves the displacement of documentary information on the artefacts. The various paper files (on collections or inventory, descriptive of the object, methodological created and classified within different departments of the Museum of Man are being replaced by digital files, or “TMS objects”, at the Musée du quai Branly. The information is not simply changing its location and material, it is being reconfigured within new interconnections of knowledge on the collections. The museum inventory is here conceived as the system that materialises a structured knowledge. To be able to analyse this system, it is necessary to link the documents’ properties to the methods used to classify them in an ad hoc space. The materiality of the media, the multiple possibilities for

  20. Friction and bending forces evaluation of AISI 304 DDQ steel sheet forming by bending tests under deep-drawing multiaxial stresses; Evaluacion de la fuerza de doblado y de friccion en el conformado de chapa de acero inoxidable AISI 304 DDQ mediante ensayos de doblado en condiciones multiaxiales de embuticion

    Energy Technology Data Exchange (ETDEWEB)

    Coello, J.; Miguel, V.; Ferrer, C.; Calatayud, A.; Martinez, A.

    2012-11-01

    Die radius is a critical area from the viewpoint of friction in forming processes. Moreover the sheet, that has been previously deformed in flange area, suffers bending and unbending stresses. Then, die-sheet contact in die radius must be especially considered in order to guarantee the suitable lubrication conditions. In the present work, a test method is carried out for evaluating an AISI 304 DDQ steel under similar conditions to those existing in the die radius area and that, usually, are not really reproduced in traditional bending under tensions tests. Deformation under pure shear condition, the bending and the radius angle have been established as variables of the tests. Results allow to obtain the apparent pressure sheet-bending tool, that increases with bending angle and decreases with tool radius. This last variable is the most significant while the bending angle has lesser influence. Although experimental results present some concordances with values obtained by analytical methods, some corrections must be considered in them in order to improve the theoretical values. (Author) 18 refs.

  1. Chlamydia - CDC Fact Sheet

    Science.gov (United States)

    ... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ( ... sheet Pelvic Inflammatory Disease (PID) – CDC fact sheet Gonorrhea – CDC fact sheet STDs Home Page Bacterial Vaginosis ( ...

  2. DP 600 steel research of dynamic testing

    Directory of Open Access Journals (Sweden)

    M. Mihaliková

    2015-01-01

    Full Text Available Dynamic tensile testing of sheet steels is becoming more important due to the need for more optimized vehicle crashworthiness analysis in the automotive industry. For generating data in dynamic conditions, was using different assay techniques. DP (dual phase steel is suitable for large complicated shape such as fenders, doors, bumpers and roofs. For experiments was used two testing method servo hydraulic and single bar method. Experiments were realized on steel grade DP 600. Steel were performed and evaluated static and dynamic tests. Microstructure and substructure in static and dynamic loading conditions was investigated.

  3. Steel making

    CERN Document Server

    Chakrabarti, A K

    2014-01-01

    "Steel Making" is designed to give students a strong grounding in the theory and state-of-the-art practice of production of steels. This book is primarily focused to meet the needs of undergraduate metallurgical students and candidates for associate membership examinations of professional bodies (AMIIM, AMIE). Besides, for all engineering professionals working in steel plants who need to understand the basic principles of steel making, the text provides a sound introduction to the subject.Beginning with a brief introduction to the historical perspective and current status of steel making together with the reasons for obsolescence of Bessemer converter and open hearth processes, the book moves on to: elaborate the physiochemical principles involved in steel making; explain the operational principles and practices of the modern processes of primary steel making (LD converter, Q-BOP process, and electric furnace process); provide a summary of the developments in secondary refining of steels; discuss principles a...

  4. Lubricant Test Methods for Sheet Metal Forming

    DEFF Research Database (Denmark)

    Bay, Niels; Olsson, David Dam; Andreasen, Jan Lasson

    2008-01-01

    Sheet metal forming of tribologically difficult materials such as stainless steel, Al-alloys and Ti-alloys or forming in tribologically difficult operations like ironing, punching or deep drawing of thick plate requires often use of environmentally hazardous lubricants such as chlorinated paraffin...... proven successful and has in a number of examples assisted the substitution of environmentally hazardous lubricants by more friendly ones in industrial production....... appearing in different sheet forming operations such as stretch forming, deep drawing, ironing and punching. The laboratory tests have been especially designed to model the conditions in industrial production. Application of the tests for evaluating new lubricants before introducing them in production has...

  5. Plasma spot welding of ferritic stainless steels

    Directory of Open Access Journals (Sweden)

    Lešnjak, A.

    2002-06-01

    Full Text Available Plasma spot welding of ferritic stainless steels is studied. The study was focused on welding parameters, plasma and shielding gases and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared. Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas, i.e., a 98 % Ar/2 % H 2 gas mixture. Tension-shear strength of plasma-spot welded joints was compared to that of resistance-spot welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a larger weld spot diameter of the former. Strength of both types of welded joints is approximately the same.

    El artículo describe el proceso de soldeo de aceros inoxidables ferríticos por puntos con plasma. La investigación se centró en el establecimiento de los parámetros óptimos de la soldadura, la definición del gas de plasma y de protección más adecuado, así como del equipo óptimo para la realización de la soldadura. Las uniones de láminas de aceros inoxidables ferríticos de 0,8 mm de espesor, soldadas a solape por puntos con plasma, se inspeccionaron visualmente y se ensayaron mecánicamente mediante el ensayo de cizalladura por tracción. Se realizaron macro pulidos. Los resultados de la investigación demostraron que la solución más adecuada para el soldeo por puntos con plasma es elegir el mismo gas de plasma que de protección. Es decir, una mezcla de 98 % de argón y 2 % de hidrógeno. La resistencia a la cizalladura por tracción de las uniones soldadas por puntos con plasma fue comparada con la resistencia de las uniones soldadas por resistencia por puntos. Se llegó a la conclusión de que las uniones soldadas por resistencia soportan una carga algo mayor que la uniones

  6. Modified Twin-Spot Laser Welding of Complex Phase Steel

    National Research Council Canada - National Science Library

    M. Różański; M. Morawiec; A. Grajcar; S. Stano

    2016-01-01

    The work addresses modified methods of twin-spot laser welding of complex phase steel sheets and investigates the effects of laser beam distribution on the macrostructure, microstructure and hardness...

  7. Fabricating interstitial-free steel with simultaneous high strength and good ductility with homogeneous layer and lamella structure

    DEFF Research Database (Denmark)

    Zhang, Ling; Chen, Zhen-Zhe; Wang, Yuhui

    2017-01-01

    Annealed interstitial-free steel (IF steel) and deformed IF steel sheets were stacked alternatively into multi-layers to produce laminated IF steel through thermal-mechanical processing. After proper processing, a yield strength of 500 MPa, an ultimate tensile strength of 600 MPa (comparable...

  8. Spring back evaluation by bending under tension tests in conditions of multiaxial stresses corresponding to deep drawing processes. Application to AISI 304 DDQ stainless steel sheet; Evaluacion del springback mediante ensayos de doblado bajo tension en condiciones de multiaxialidad tipicas de los procesos de embuticion profunda. Aplicacion a chapa de acero inoxidable AISI 304 DDQ

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, V.; Coello, J.; Martinez, A.; Calatayud, A.

    2013-09-01

    In this paper, a methodology has been developed for evaluating the spring back of AISI 304 DDQ stainless steel sheet based on a bending under tension test. The main difference of the methodology herein carried out is that tests are made under the multiaxial stresses state that take place in deep drawing processes. This affects to the level of stress value in the test and to the hardening state of the sheet. Springback evaluation has been done in two different areas. Bending area has been evaluated from elastic recovery ratio defined as the ratio between the bending radius after and before bending. Bending and unbending extreme has been studied from the measured curvature radius in this area and taking into account the geometric equivalence of the test with the drawing cups process. Results found allow to state that drawing ratio or deformation ratio have a negligible influence on the springback into the range of values experimented here. Bending radius has hardly influence as well while bending angle is the most significant variable. The results obtained are compared to those measured in deep-drawn cups, finding a great agreement. (Author)

  9. Zika Virus Fact Sheet

    Science.gov (United States)

    ... sheets Fact files Questions & answers Features Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... and last for 2-7 days. Complications of Zika virus disease Based on a systematic review of the ...

  10. Cholera Fact Sheet

    Science.gov (United States)

    ... sheets Fact files Questions & answers Features Multimedia Contacts Cholera Fact sheet Updated December 2017 Key facts Cholera ... behaviour and to the control of cholera. Oral cholera vaccines Currently there are three WHO pre-qualified ...

  11. BEHAVIOR OF STEEL DP 600 UNDER DYNAMIC CONDITIONS

    Directory of Open Access Journals (Sweden)

    Miroslav Német

    2014-01-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 Dynamic tensile testing of sheet steels is becoming more important. Experimental dynamic tensile technique is depending on the strain rate. For experiments was used two testing method servo hydraulic and single bar method. Experiments was realized on steel grade DP 600. Steel were performed and evaluated static and dynamic tests. Was investigated substructure in static and dynamic loading conditions.

  12. Clinching for sheet materials

    OpenAIRE

    He, XiaoCong

    2017-01-01

    Abstract Latest developments in the clinching of sheet materials are reviewed in this article. Important issues are discussed, such as tool design, process parameters and joinability of some new lightweight sheet materials. Hybrid and modified clinching processes are introduced to a general reader. Several unaddressed issues in the clinching of sheet materials are identified.

  13. Modélisation du procédé de soudage hybride Arc / Laser par une approche level set application aux toles d'aciers de fortes épaisseurs A level-set approach for the modelling of hybrid arc/laser welding process application for high thickness steel sheets joining

    Directory of Open Access Journals (Sweden)

    Desmaison Olivier

    2013-11-01

    Full Text Available Le procédé de soudage hybride Arc/Laser est une solution aux assemblages difficiles de tôles de fortes épaisseurs. Ce procédé innovant associe deux sources de chaleur : un arc électrique produit par une torche MIG et une source laser placée en amont. Ce couplage améliore le rendement du procédé, la qualité du cordon et les déformations finales. La modélisation de ce procédé par une approche Level Set permet une prédiction du développement du cordon et du champ de température associé. La simulation du soudage multi-passes d'une nuance d'acier 18MnNiMo5 est présentée ici et les résultats sont comparés aux observations expérimentales. The hybrid arc/laser welding process has been developed in order to overcome the difficulties encountered for joining high thickness steel sheets. This innovative process gathers two heat sources: an arc source developed by a MIG torch and a pre-located laser source. This coupling improves the efficiency of the process, the weld bead quality and the final deformations. The Level-Set approach for the modelling of this process enables the prediction of the weld bead development and the temperature field evolution. The simulation of the multi-passes welding of a 18MnNiMo5 steel grade is detailed and the results are compared to the experimental observations.

  14. Crack Propagation on ESE(T) Specimens Strengthened with CFRP Sheets

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Jensen, Peter Holmstrøm; Dyrelund, Jens

    2009-01-01

    In this paper fatigue tests on side notched steel test specimens strengthened with adhesive bonded fibre reinforced polymer (FRP) sheets are presented. The specimens are subject to crack growth both in the steel and bond line. Influence of the load ratio and initial crack length on the overall en...

  15. Tool steels

    DEFF Research Database (Denmark)

    Højerslev, C.

    2001-01-01

    On designing a tool steel, its composition and heat treatment parameters are chosen to provide a hardened and tempered martensitic matrix in which carbides are evenly distributed. In this condition the matrix has an optimum combination of hardness andtoughness, the primary carbides provide...... resistance against abrasive wear and secondary carbides (if any) increase the resistance against plastic deformation. Tool steels are alloyed with carbide forming elements (Typically: vanadium, tungsten, molybdenumand chromium) furthermore some steel types contains cobalt. Addition of alloying elements...... serves primarily two purpose (i) to improve the hardenabillity and (ii) to provide harder and thermally more stable carbides than cementite. Assuming proper heattreatment, the properties of a tool steel depends on the which alloying elements are added and their respective concentrations....

  16. Effect of strain path change on limits to ductility of anisotropic metal sheets

    DEFF Research Database (Denmark)

    Kuroda, M.; Tvergaard, Viggo

    2000-01-01

    plasticity models to fit a set of experimental data for cold-rolled steel sheet. The predicted forming limit diagrams show strong dependence on whether or not the load on the sheet is removed between two load steps on a non-proportional strain path. This dependence is investigated in detail for one...

  17. A System of Test Methods for Sheet Metal Forming Tribology

    DEFF Research Database (Denmark)

    Bay, Niels; Olsson, David Dam; Andreasen, Jan Lasson

    2007-01-01

    Sheet metal forming of tribologically difficult materials such as stainless steel, Al-alloys and Ti-alloys or forming in tribologically difficult operations like ironing, punching or deep drawing of thick plate requires often use of environmentally hazardous lubricants such as chlorinated paraffin...

  18. Weldability of Additive Manufactured Stainless Steel

    Science.gov (United States)

    Matilainen, Ville-Pekka; Pekkarinen, Joonas; Salminen, Antti

    Part size in additive manufacturing is limited by the size of building area of AM equipment. Occasionally, larger constructions that AM machines are able to produce, are needed, and this creates demand for welding AM parts together. However there is very little information on welding of additive manufactured stainless steels. The aim of this study was to investigate the weldability aspects of AM material. In this study, comparison of the bead on plate welds between AM parts and sheet metal parts is done. Used material was 316L stainless steel, AM and sheet metal, and parts were welded with laser welding. Weld quality was evaluated visually from macroscopic images. Results show that there are certain differences in the welds in AM parts compared to the welds in sheet metal parts. Differences were found in penetration depths and in type of welding defects. Nevertheless, this study presents that laser welding is suitable process for welding AM parts.

  19. Laser cutting of sheets for Tailored Blanks

    DEFF Research Database (Denmark)

    Bagger, Claus; Olsen, Flemming Ove

    1999-01-01

    Over the past few years there has been an enormous increase in the use of tailored blanks, especially in the automotive industry. Often the sheets for tailored blanks are shear cut, but results have been reported that the allowable sheet gap distance should not exceed 0.1 mm in order to obtain...... sound welds. Laser cutting the sheets may therefore be an alternative to shear cutting, if the cut kerf squareness can be kept below 0.05 mm.In a number of systematic laboratory experiments the effects of the major process parameters in laser cutting have been investigated. Each cut was quantified...... by the squareness, the surface roughness and the burr height. Mild steel as well as high strength steel with and with out galvanisation with thickness' of 0.7(5) and 1.25 were used.In the tests the difference in cut quality between a 5" and a 7.5" focusing lens were tested and the effect of using pulsed mode laser...

  20. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions....... On page 590 of this issue, MacGregor et al. (2) estimate the mean rates of snow accumulation and ice flow of the Greenland Ice Sheet over the past 9000 years based on an ice sheet-wide dated radar stratigraphy (3). They show that the present changes of the Greenland Ice Sheet are partly an ongoing...... response to the last deglaciation. The results help to clarify how sensitive the ice sheet is to climate changes....

  1. Analysis of the Behaviour of Composite Steel and Steel Fiber Reinforced Concrete Slabs

    Directory of Open Access Journals (Sweden)

    Mindaugas Petkevičius

    2011-04-01

    Full Text Available There was a pending influence of steel fiber on the strength and stiffness of composite steel–concrete slabs under statical short–time load. Steel profiled sheeting and steel fiber reinforced concrete were used for specimens. Four composite slabs were made. Experimental investigations into the behaviour and influence of steel fiber reinforced concrete in composite slabs were conducted. Transverse, longitudinal, shear deformation and deflection of the slab were measured. The results indicated that the use of steel fiber in composite slabs was effective: strength was 20–24 % higher and the meanings of deflections under the action of the bending moment were 0,6MR (where MR is the bending moment at failure of the slabs and were 16–18 % lower for slabs with usual concrete. Article in Lithuanian

  2. Titanium Sheet Fabricated from Powder for Industrial Applications

    Energy Technology Data Exchange (ETDEWEB)

    Peter, William H [ORNL; Muth, Thomas R [ORNL; Chen, Wei [ORNL; Yamamoto, Yukinori [ORNL; Jolly, Brian C [ORNL; Stone, Nigel [CSIRO ICT Center, Australia; Cantin, G.M.D. [CSIRO ICT Center, Australia; Barnes, John [CSIRO ICT Center, Australia; Paliwal, Muktesh [Ametek, Inc.; Smith, Ryan [Ametek, Inc.; Capone, Joseph [Ametek, Inc.; Liby, Alan L [ORNL; Williams, James C [Ohio State University; Blue, Craig A [ORNL

    2012-01-01

    In collaboration with Ametek and Commonwealth Scientific and Industrial Research Organization (CSIRO), Oak Ridge National Laboratory has evaluated three different methods for converting titanium hydride-dehydride (HDH) powder into thin gauge titanium sheet from a roll compacted preform. Methodologies include sintering, followed by cold rolling and annealing; direct hot rolling of the roll-compacted sheet; and hot rolling of multiple layers of roll compacted sheet that are encapsulated in a steel can. All three methods have demonstrated fully consolidated sheet, and each process route has the ability to produce sheet that meets ASTM B265 specifications. However, not every method currently provides sheet that can be highly formed without tearing. The degree of sintering between powder particles, post processing density, and the particle to particle boundary layer where compositional variations may exist, have a significant effect on the ability to form the sheet into useful components. Uniaxial tensile test results, compositional analysis, bend testing, and biaxial testing of the titanium sheet produced from hydride-dehydride powder will be discussed. Multiple methods of fabrication and the resulting properties can then be assessed to determine the most economical means of making components for industrial applications.

  3. Thermoforming of foam sheet

    NARCIS (Netherlands)

    Akkerman, Remko; Pronk, Ruud M.

    1997-01-01

    Thermoforming is a widely used process for the manufacture of foam sheet products. Polystyrene foam food trays for instance can be produced by first heating the thermoplastic foam sheet, causing the gas contained to build up pressure and expand, after which a vacuum pressure can be applied to draw

  4. Forming of High-strength Steels Using a Hot-melt Dry Lubricant

    DEFF Research Database (Denmark)

    Hörnström, Sven-Erik; Karlsson, Erik; Olsson, Mikael

    2008-01-01

    with a conventional rust protection oil using four different tests methods, i.e. a strip reduction test, a bending under tension test, a stretch-forming test and a pin-on disc test. In the tests, two different cold work tool steels, a conventional steel grade and a nitrogen alloyed PM steel grade were evaluated...... show that the dry lubricant provides better lubrication and generates less galling than the rust protection oil. Also, the nitrogen alloyed PM steel grade shows a significantly higher galling resistance as compared with the conventional steel grade and can, in combination with a dry lubricant......The increasing use of high strength steels in a variety of mechanical engineering applications has illuminated problems associated with galling in sheet metal forming operations. Galling is a tribological phenomenon associated with transfer of material from the steel sheet to the tool surface...

  5. Hegelian Steel

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    2015-01-01

    . Developing a Hegelian inspired historical-sociological approach this paper however argues that national and transnational societies emerged simultaneously and in a co-evolutionary and mutually supportive fashion. In most European settings national societies did not become the central horizon of individuals...... of the European steel industry....

  6. Algebra task & drill sheets

    CERN Document Server

    Reed, Nat

    2011-01-01

    For grades 6-8, our State Standards-based combined resource meets the algebraic concepts addressed by the NCTM standards and encourages the students to review the concepts in unique ways. The task sheets introduce the mathematical concepts to the students around a central problem taken from real-life experiences, while the drill sheets provide warm-up and timed practice questions for the students to strengthen their procedural proficiency skills. Included are opportunities for problem-solving, patterning, algebraic graphing, equations and determining averages. The combined task & drill sheets

  7. Solar cell sheet. Taiyo denchi sheet

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kazutomi; Nakatani, Kenji; Okaniwa, Hiroshi.

    1989-08-09

    This invention consists of a module sheet containing a thin film solar cell formed on a polymer film substrate, a cushioning sticky film layer and a protective film layer; thickness of module sheet is less than 1000 micron and its bending rigidity of 5 mm thick sample is less than 100 kg-mm {sup 2}. By this, the soalr cell can be wound and unwound in small roll of several cm level. This eliminates the internal wiring in the plural number of cells giving high durability of integrated amorphous solar cell against the repeated bending. The polymer film is films of PET, polysulphone, polyamide, with proper thickness of 30 - 300 micron. 2 figs.

  8. União de juntas dissimilares alumínio-aço de chapas finas pelo processo de soldagem por atrito com pino não consumível (SAPNC Dissimilar joint of aluminum-steel thin sheet by friction stir welding process

    Directory of Open Access Journals (Sweden)

    Edwar Andrés Torres

    2011-09-01

    Full Text Available Foram obtidas juntas dissimilares da liga de alumínio 6063-T5 e do aço AISI SAE 1020 com espessura de 2,0 mm soldadas por atrito com pino não consumível. O objetivo deste trabalho é avaliar o efeito da penetração e o deslocamento da ferramenta na obtenção de juntas soldadas Al-aço. As juntas foram avaliadas segundo a qualidade da superfície e a profundidade da região soldada. Foi determinado que além das velocidades de rotação (ω e avanço (ν, o deslocamento e a profundidade de penetração da ferramenta são parâmetros fundamentais, pois definem o aporte térmico e, com este, a aderência ou não de alumínio na ferramenta, a qualidade superficial e a formação de defeitos ao longo da linha da junta.Aluminum alloy 6063-T5 and AISI SAE 1020 were obtained with dissimilar welded joints by friction stir welding in 2.0 mm thick sheet. The aim was to evaluate the effect of welding parameters to obtain Al-steel welds. Joints were evaluated according to surface quality and depth of the welded region. It was determined that besides the rotational (ω and forward (ν speeds, the offset and the tool penetration are key parameters because they define the heat input and therefore the adherence of aluminum in the tool, the surface quality and defect formation along the joint line.

  9. Zika Virus Fact Sheet

    Science.gov (United States)

    ... Fact files Questions & answers Features Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... last for 2-7 days. Complications of Zika virus disease Based on a systematic review of the ...

  10. Avian Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    NWCC Wildlife Work Group

    2004-12-01

    OAK-B135 After conducting four national research meetings, producing a document guiding research: Metrics and Methods for Determining or Monitoring Potential Impacts on Birds at Existing and Proposed Wind Energy Sites, 1999, and another paper, Avian Collisions with Wind Turbines: A Summary of Existing Studies and Comparisons to Other Sources of Avian Collision Mortality in the United States, 2001, the subcommittee recognized a need to summarize in a short fact sheet what is known about avian-wind interaction and what questions remain. This fact sheet attempts to summarize in lay terms the result of extensive discussion about avian-wind interaction on land. This fact sheet does not address research conducted on offshore development. This fact sheet is not intended as a conclusion on the subject; rather, it is a summary as of Fall/Winter 2002.

  11. Sepsis Fact Sheet

    Science.gov (United States)

    ... Education About NIGMS NIGMS Home > Science Education > Sepsis Sepsis Tagline (Optional) Middle/Main Content Area PDF Version ( ... KB) En español Other Fact Sheets What is sepsis? Sepsis is a serious medical condition. It is ...

  12. Sheet electron beam tester

    Science.gov (United States)

    Spear, Alexander Grenbeaux

    The DARPA HiFIVE project uses a pulsed electron sheet beam gun to power a traveling wave tube amplifier operating at 220 GHz. Presented is a method for characterizing the high current density 0.1 mm by 1 mm sheet electron beam. A tungsten tipped probe was scanned through the cross section of the sheet electron beam inside of a vacuum vessel. The probe was controlled with sub-micron precision using stepper motors and LabView computer control while boxcar averaging hardware sampled the pulsed beam. Matlab algorithms were used to interpret the data, calculate beam dimensions and current density, and create 2-dimensional cross section images. Full characterization of two separate HiFIVE sheet electron guns was accomplished and is also presented.

  13. Trauma Fact Sheet

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Physical Trauma Physical Trauma Tagline (Optional) Middle/Main Content Area PDF Version (572 KB) Other Fact Sheets What is physical trauma? Physical trauma is a serious injury to the ...

  14. Burns Fact Sheet

    Science.gov (United States)

    ... of most of these problems is the body’s explosive inflammatory response. A normal inflammatory response protects the ... your website or other digital platform? This fact sheet and others are available for syndication through the ...

  15. DAR ES SALAAM, TANZANIA

    African Journals Online (AJOL)

    Othman-Specialion of Cadmium, Copper , Lead and Zinc in Msimbazi river ... Samples of water were taken from river Msimbazi that runs through the city of Dar es ... immediately subjected to laboratory analysis and when necessary stored in a.

  16. Comparative Study between Programming Systems for Incremental Sheet Forming Process

    Directory of Open Access Journals (Sweden)

    Moayedfar Majid

    2014-07-01

    Full Text Available Incremental Sheet Forming (ISF is a method developed to form a desired surface feature on sheet metals in batch production series. Due to a lack of dedicated programming system to execute, control and monitor the whole ISF, researchers tried to utilize programming systems designed for chip making process to suits for ISF. In this work, experiments were conducted to find suitability and quality of ISF parts produced by using manual CNC part programming. Therefore, ISF was carried out on stainless steel sheets using Computer Numerical Control (CNC milling machines. Prior to running the experiments, a ball-point shaped tool made of bronze alloy was fabricated due to its superior ability to reduce the amount of friction and improve the surface quality of the stainless steel sheet metal. The experiments also employed the method of forming in negative direction with a blank mould and the tool which helped to shape the desired part quickly. The programming was generated using the MasterCAM software for the CNC milling machine and edited before transferring to the machine. However, the programming for the machine was written manually to show the differences of output date between software programming and manual programming. From the results, best method of programming was found and minimum amount of contact area between tool and sheet metal achieved.

  17. Magnetic Barkhausen emission in lightly deformed AISI 1070 steel

    Energy Technology Data Exchange (ETDEWEB)

    Capo Sanchez, J., E-mail: jcapo@cnt.uo.edu.cu [Departamento de Fisica, Facultad de Ciencias Naturales, Universidad de Oriente, Av. Patricio Lumumba s/n, 90500 Santiago de Cuba (Cuba); Campos, M.F. de [EEIMVR-Universidade Federal Fluminense, Av. dos Trabalhadores 420, Vila Santa Cecilia, 27255-125 Volta Redonda, RJ (Brazil); Padovese, L.R. [Departamento de Engenharia Mecanica, Escola Politecnica, Universidade de Sao Paulo, Av. Prof. Mello Moraes, 2231, 05508-900 Sao Paulo (Brazil)

    2012-01-15

    The Magnetic Barkhausen Noise (MBN) technique can evaluate both micro- and macro-residual stresses, and provides indication about the relevance of contribution of these different stress components. MBN measurements were performed in AISI 1070 steel sheet samples, where different strains were applied. The Barkhausen emission is also analyzed when two different sheets, deformed and non-deformed, are evaluated together. This study is useful to understand the effect of a deformed region near the surface on MBN. The low permeability of the deformed region affects MBN, and if the deformed region is below the surface the magnetic Barkhausen signal increases. - Highlights: > Evaluated residual stresses by the magnetic Barkhausen technique. > Indication about the relevance of micro-and macro-stress components. > Magnetic Barkhausen measurements were carried out in AISI 1070 steel sheet samples. > Two different sheets, deformed and non-deformed, are evaluated together. > Magnetic Barkhausen signal increases when deformed region is below the surface.

  18. Biodiesel Basics (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-06-01

    This fact sheet provides a brief introduction to biodiesel, including a discussion of biodiesel blends, which blends are best for which vehicles, where to buy biodiesel, how biodiesel compares to diesel fuel in terms of performance, how biodiesel performs in cold weather, whether biodiesel use will plug vehicle filters, how long-term biodiesel use may affect engines, biodiesel fuel standards, and whether biodiesel burns cleaner than diesel fuel. The fact sheet also dismisses the use of vegetable oil as a motor fuel.

  19. Energy information sheets

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  20. Diatomées

    African Journals Online (AJOL)

    Impact environnemental et évaluation de la qualité des eaux par des méthodes chimiques et biologiques « Diatomées » ... possèdent un caractère alcaliphyle prononcé avec une abondance des espèces résistantes à la pollution organique. Mots clés : Diatomées, qualité de l'eau, bio-indicateur, IDL, IPO, Merja Fouarat.

  1. Computer Assisted Estimating of Steel Fabrication and Erection.

    Science.gov (United States)

    1987-01-01

    field by iron workers. (12: 116) j Steel fabrication shops require a high investment in plant facilities and shop equipment. Fabricators tend to...specialize in either heavy structural steel or miscellaneous metals due to the significant differences in 3equipment, plant layout, and labor skills...8 ~lie THE WOP4SHEE-T ESTIMATE ESIAEWOFI SHEET CASE STUD’ WODi SHEK E F’ - :::w~ -: . P DIMEN WEIGHT SHOP H4 PLT HDAF HP jTH NITOT MATF LS RF" 198 SFA

  2. Testing of Lubricant Performance in Sheet Metal Forming

    DEFF Research Database (Denmark)

    Bay, Niels; Olsson, David Dam; Friis, Kasper Leth

    2008-01-01

    difficult sheet materials such as high strength steels and stainless steels, and when the forming process itself due to high normal pressures causes substantial temperature increase in the tool/work piece interface. Higher temperatures lead to thinner lubricant films and the risk of galling, i.e. breakdown...... of the lubricant film causing pick-up of work piece material on the tool surface and scoring of subsequent work piece surfaces. The present paper gives an overview of more than 10 years work by the authors’ research group through participation in national as well as international framework programmes on developing...

  3. Influence of electrical sheet width on dynamic magnetic properties

    CERN Document Server

    Chevalier, T; Cornut, B

    2000-01-01

    Effects of the width of electrical steel sheets on dynamic magnetic properties are investigated by solving diffusion equation on the cross-section of the sheet. Linear and non-linear cases are studied, and are compared with measurement on Epstein frame. For the first one an analytical solution is found, while for the second, a 2D finite element simulation is achieved. The influence of width is highlighted for a width thickness ratio lower than 10. It is shown that the behaviour modification in such cases is conditioned by the excitation signal waveform, amplitude and also frequency.

  4. NADAR ES LA CLAVE

    Directory of Open Access Journals (Sweden)

    MANUEL RUIZ C.

    2015-03-01

    Full Text Available Claro, la clave es nadar, nadar para crecer y trascender.  Pues, es el agua, el fluido mágico en el cual se dinamiza  nuestro cuerpo en forma sensorial, y en donde el espíritu  se recrea, mientras la mente se complace al comprender,  que es la natación, la que compromete al ser en su totalidad  y lo funde en una perfecta unidad funcional;  cuerpo y mente, soma y psiquis, sensaciones y sentimientos.

  5. Finishes for Metals. Paintability of Galvanized Steel, Corrosion Resistance of Metallized Coatings.

    Science.gov (United States)

    Building Research Inst., Inc., Washington, DC.

    Two papers are presented. The first, "Report of the AISI Research Project on the Paintability of Galvanized Steel," was a project aimed at determining optimum procedures for painting bright-spangled galvanized sheet steel products using three classes of trade sales paints--metallic zinc-dust, portland cement-in-oil, and water base emulsion paints.…

  6. Laser welded steel sandwich panel bridge deck development : finite element analysis and stake weld strength tests.

    Science.gov (United States)

    2009-09-01

    This report summarizes the analysis of laser welded steel sandwich panels for use in bridge structures and : static testing of laser stake welded lap shear coupons. Steel sandwich panels consist of two face sheets : connected by a relatively low-dens...

  7. Influence of surface texture on the galling characteristics of lean duplex and austenitic stainless steels

    DEFF Research Database (Denmark)

    Wadman, Boel; Eriksen, J.; Olsson, M.

    2010-01-01

    Two simulative test methods were used to study galling in sheet forming of two types of stainless steel sheet: austenitic (EN 1.4301) and lean duplex LDX 2101 (EN 1.4162) in different surface conditions. The pin-on-disc test was used to analyse the galling resistance of different combinations...

  8. Safety advice sheets

    CERN Multimedia

    HSE Unit

    2013-01-01

    You never know when you might be faced with questions such as: when/how should I dispose of a gas canister? Where can I find an inspection report? How should I handle/store/dispose of a chemical substance…?   The SI section of the DGS/SEE Group is primarily responsible for safety inspections, evaluating the safety conditions of equipment items, premises and facilities. On top of this core task, it also regularly issues “Safety Advice Sheets” on various topics, designed to be of assistance to users but also to recall and reinforce safety rules and procedures. These clear and concise sheets, complete with illustrations, are easy to display in the appropriate areas. The following safety advice sheets have been issued so far: Other sheets will be published shortly. Suggestions are welcome and should be sent to the SI section of the DGS/SEE Group. Please send enquiries to general-safety-visits.service@cern.ch.

  9. R-ES-ONANCEI

    Indian Academy of Sciences (India)

    A Tribute. H R Krishnamurthy. 70 John Maynard Smith (1920-2004). NOne of the last Grand Evolutionary Theorists of the 20th. Century'". Vidyanand Nanjundiah. BOOK REVIEWS. 93 Indian Mathematics and Astronomy - Some. Landmarks. B Sury. -6--------------------------~---------R-ES-O-N-A-N-C-E-I--N-ov-e-m-be-r-2-o--o5 ...

  10. COSIMA-ES-PORT

    DEFF Research Database (Denmark)

    Barfod, Michael Bruhn; Leleur, Steen

    2007-01-01

    -ES-PORT model showed some promising perspectives in the handling of the three pre-feasibility studies. Parameters such as cargo handling and ship related issues could with advantage be implemented in the decision model and forecasted similarly to road infrastructure impacts. Furthermore, the development...

  11. Es imposible no comunicar

    Directory of Open Access Journals (Sweden)

    Joan Costa y Solá-Segalés

    2012-04-01

    Full Text Available La confusión entre "comunicar" y "significar" proviene del hecho de que la comunicación transporta significados, pero también se producen significados fuera del proceso de comunicación. Es lo que llamamos "semiosis no comunicativa".

  12. Energy information sheets

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-02

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. Written for the general public, the EIA publication Energy Information Sheets was developed to provide information on various aspects of fuel production, prices, consumption and capability. The information contained herein pertains to energy data as of December 1991. Additional information on related subject matter can be found in other EIA publications as referenced at the end of each sheet.

  13. Ice Sheets & Ice Cores

    DEFF Research Database (Denmark)

    Mikkelsen, Troels Bøgeholm

    Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known...... as Dansgaard-Oeschger (DO) events would add to our knowledge of the climatic system and – hopefully – enable better forecasts. Likewise, to forecast possible future sea level rise it is crucial to correctly model the large ice sheets on Greenland and Antarctica. This project is divided into two parts...

  14. Sheet molding composite recycling

    Energy Technology Data Exchange (ETDEWEB)

    Jost, K.

    1995-08-01

    This article describes how the SMC Automotive Alliance is helping to develop commercial processes to convert sheet molding composite scrap into new raw materials. A projected 200 million pounds of sheet molding composite (SMC) will be used by the auto industry in 1995. The increasing use of SMC in automobiles has prompted the industry to resolve some of the technical challenges involved with recycling the material. The SMC Automotive Alliance, composed of 30 molders and raw materials suppliers, has implemented cooperative research and development programs that have led to the commercialization of processes to recycle and reuse both postindustrial and eventually post-consumer SMC in new automotive applications.

  15. Mini-tensile specimen application for sheets characterization

    Science.gov (United States)

    Džugan, J.; Rund, M.; Prantl, A.; Konopík, P.

    2017-02-01

    There are many cases when there is a shortage of the experimental material for detailed analysis and then small size specimens techniques becomes essential. The current paper deals with investigations of mini-tensile tests (MTT) application to metal sheets characterization. In the case of metal sheets assessment the most common are tensile tests for Lankford parameters and strain hardening determination. As most of the processes are not quasi-static and constant strain rate processes, thus assessment of strain rate hardening is also crucial part of the characterization. Previously developed and verified testing procedure of M-TTs for bulk materials is applied here for steel sheet made of DC01 characterization. Tests under quasi-static and dynamic loading conditions are carried out in order to describe above mentioned properties at room temperature. Accurate strain measurement is carried out with digital image correlation systems and results obtained with M-TTs are going to be confronted with standard size specimens’ results.

  16. Production (information sheets)

    NARCIS (Netherlands)

    2007-01-01

    Documentation sheets: Geo energy 2 Integrated System Approach Petroleum Production (ISAPP) The value of smartness 4 Reservoir permeability estimation from production data 6 Coupled modeling for reservoir application 8 Toward an integrated near-wellbore model 10 TNO conceptual framework for "E&P

  17. Collisionless current sheet equilibria

    Science.gov (United States)

    Neukirch, T.; Wilson, F.; Allanson, O.

    2018-01-01

    Current sheets are important for the structure and dynamics of many plasma systems. In space and astrophysical plasmas they play a crucial role in activity processes, for example by facilitating the release of magnetic energy via processes such as magnetic reconnection. In this contribution we will focus on collisionless plasma systems. A sensible first step in any investigation of physical processes involving current sheets is to find appropriate equilibrium solutions. The theory of collisionless plasma equilibria is well established, but over the past few years there has been a renewed interest in finding equilibrium distribution functions for collisionless current sheets with particular properties, for example for cases where the current density is parallel to the magnetic field (force-free current sheets). This interest is due to a combination of scientific curiosity and potential applications to space and astrophysical plasmas. In this paper we will give an overview of some of the recent developments, discuss their potential applications and address a number of open questions.

  18. Ethanol Basics (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-01-01

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  19. Respirator Fact Sheet

    Science.gov (United States)

    ... wear the escape hood and get the expected protection? Respirator Fact Sheet [PDF - 706 KB] Follow NIOSH Facebook Flickr Pinterest Twitter ... PDF, DOC, PPT, MPEG) on this site? Adobe PDF file Microsoft PowerPoint file Microsoft Word ... last updated: June 6, 2014 Content source: National Institute for Occupational Safety and Health Education ...

  20. Automated Steel Cleanliness Analysis Tool (ASCAT)

    Energy Technology Data Exchange (ETDEWEB)

    Gary Casuccio (RJ Lee Group); Michael Potter (RJ Lee Group); Fred Schwerer (RJ Lee Group); Dr. Richard J. Fruehan (Carnegie Mellon University); Dr. Scott Story (US Steel)

    2005-12-30

    The objective of this study was to develop the Automated Steel Cleanliness Analysis Tool (ASCATTM) to permit steelmakers to evaluate the quality of the steel through the analysis of individual inclusions. By characterizing individual inclusions, determinations can be made as to the cleanliness of the steel. Understanding the complicating effects of inclusions in the steelmaking process and on the resulting properties of steel allows the steel producer to increase throughput, better control the process, reduce remelts, and improve the quality of the product. The ASCAT (Figure 1) is a steel-smart inclusion analysis tool developed around a customized next-generation computer controlled scanning electron microscopy (NG-CCSEM) hardware platform that permits acquisition of inclusion size and composition data at a rate never before possible in SEM-based instruments. With built-in customized ''intelligent'' software, the inclusion data is automatically sorted into clusters representing different inclusion types to define the characteristics of a particular heat (Figure 2). The ASCAT represents an innovative new tool for the collection of statistically meaningful data on inclusions, and provides a means of understanding the complicated effects of inclusions in the steel making process and on the resulting properties of steel. Research conducted by RJLG with AISI (American Iron and Steel Institute) and SMA (Steel Manufactures of America) members indicates that the ASCAT has application in high-grade bar, sheet, plate, tin products, pipes, SBQ, tire cord, welding rod, and specialty steels and alloys where control of inclusions, whether natural or engineered, are crucial to their specification for a given end-use. Example applications include castability of calcium treated steel; interstitial free (IF) degasser grade slag conditioning practice; tundish clogging and erosion minimization; degasser circulation and optimization; quality assessment/steel

  1. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    Unknown

    Department of Applied Mechanics and Hydraulics, Regional Engineering. College, Rourkela 769 008, India. MS received 29 November 2001; revised 24 June 2002. Abstract. A fatigue crack can be effectively retarded by heating a spot near the crack ...

  2. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    A fatigue crack can be effectively retarded by heating a spot near the crack tip under nil remote stress condition. The subcritical spot heating at a proper position modifies the crack growth behaviour in a way, more or less, similar to specimen subjected to overload spike. It is observed that the extent of crack growth retardation ...

  3. Formability Characterization of a New Generation High Strength Steels

    Energy Technology Data Exchange (ETDEWEB)

    Sriram Sadagopan; Dennis Urban; Chris Wong; Mai Huang; Benda Yan

    2003-05-16

    Advanced high strength steels (AHSS) are being progressively explored by the automotive industry all around the world for cost-effective solutions to accomplish vehicle lightweighting, improve fuel economy, and consequently reduce greenhouse emissions. Because of their inherent high strength, attractive crash energy management properties, and good formability, the effective use of AHSS such as Duel Phase and TRIP (Transformation Induced Plasticity) steels, will significantly contribute to vehicle lightweighting and fuel economy. To further the application of these steels in automotive body and structural parts, a good knowledge and experience base must be developed regarding the press formability of these materials. This project provides data on relevant intrinsic mechanical behavior, splitting limits, and springback behavior of several lots of mild steel, conventional high strength steel (HSS), advanced high strength steel (AHSS) and ultra-high strength steel (UHSS), supplied by the member companies of the Automotive Applications Committee (AAC) of the American Iron and Steel Institute (AISI). Two lots of TRIP600, which were supplied by ThyssenKrupp Stahl, were also included in the study. Since sheet metal forming encompasses a very diverse range of forming processes and deformation modes, a number of simulative tests were used to characterize the forming behavior of these steel grades. In general, it was found that formability, as determined by the different tests, decreased with increased tensile strength. Consistant with previous findings, the formability of TRIP600 was found to be exceptionally good for its tensile strength.

  4. Welding of AM350 and AM355 steel

    Science.gov (United States)

    Davis, R. J.; Wroth, R. S.

    1967-01-01

    A series of tests was conducted to establish optimum procedures for TIG welding and heat treating of AM350 and AM355 steel sheet in thicknesses ranging from 0.010 inch to 0.125 inch. Statistical analysis of the test data was performed to determine the anticipated minimum strength of the welded joints.

  5. Plasma nitriding of steels

    CERN Document Server

    Aghajani, Hossein

    2017-01-01

    This book focuses on the effect of plasma nitriding on the properties of steels. Parameters of different grades of steels are considered, such as structural and constructional steels, stainless steels and tools steels. The reader will find within the text an introduction to nitriding treatment, the basis of plasma and its roll in nitriding. The authors also address the advantages and disadvantages of plasma nitriding in comparison with other nitriding methods. .

  6. Rubella - Fact Sheet for Parents

    Science.gov (United States)

    ... this page: About CDC.gov . Redirect for the Rubella fact sheet page. The current fact sheet can ... http://www.cdc.gov/vaccines/parents/diseases/child/rubella.html Print page Share Compartir File Formats Help: ...

  7. Light Sheet Fluorescence Microscopy

    Science.gov (United States)

    Santi, Peter A.

    2011-01-01

    Light sheet fluorescence microscopy (LSFM) functions as a non-destructive microtome and microscope that uses a plane of light to optically section and view tissues with subcellular resolution. This method is well suited for imaging deep within transparent tissues or within whole organisms, and because tissues are exposed to only a thin plane of light, specimen photobleaching and phototoxicity are minimized compared to wide-field fluorescence, confocal, or multiphoton microscopy. LSFMs produce well-registered serial sections that are suitable for three-dimensional reconstruction of tissue structures. Because of a lack of a commercial LSFM microscope, numerous versions of light sheet microscopes have been constructed by different investigators. This review describes development of the technology, reviews existing devices, provides details of one LSFM device, and shows examples of images and three-dimensional reconstructions of tissues that were produced by LSFM. PMID:21339178

  8. Biomolecular Science (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-04-01

    A brief fact sheet about NREL Photobiology and Biomolecular Science. The research goal of NREL's Biomolecular Science is to enable cost-competitive advanced lignocellulosic biofuels production by understanding the science critical for overcoming biomass recalcitrance and developing new product and product intermediate pathways. NREL's Photobiology focuses on understanding the capture of solar energy in photosynthetic systems and its use in converting carbon dioxide and water directly into hydrogen and advanced biofuels.

  9. Honda Civic fact sheet

    Energy Technology Data Exchange (ETDEWEB)

    NREL

    1999-05-01

    The U.S. Department of Energy (DOE) is promoting the use of alternative fuels and alternative fuel vehicles (AFVs). The National Renewable Energy Laboratory (NREL) has been directed to conduct projects to evaluate the performance and acceptability of light-duty AFVs. This fact sheet describes the test results on 1998 Honda Civics: one dedicated CNG and a gasoline model as closely matched as possible.

  10. Development of environmentally friendly non-chrome conversion coatings for cold-rolled steel

    Science.gov (United States)

    Zhang, Jinming

    Steel producers use various organic and inorganic coatings to protect cold-rolled steel (CRS) sheets from corrosion during shipment and storage. It is well known that CRS sheets can be protected from corrosion by galvanizing, phosphating, chromating, topcoating with organic, or their combinations. The chromate rinsing is particularly effective for preventing white rusting of galvanized steel. But there is an increasing interest in a replacement for the chromating process because of environmental and health concerns. The objective of the present work is to develop a chrome-free conversion coating for steel sheets. Various carboxylic acids and their salts have been studied for coating phosphated electrogalvanized (EG) steel sheets, including 10-undecenoic acid (UA), oleic acid (OA), and other fatty acids such as stearic acid (SA) and palmitic acid (PA). When they were used alone, or subsequently coated with resin, they could produce a highly hydrophobic surface and improve the corrosion resistance. Thiols such as 1-octadecanethiol (ODT) can form a self-assembled monolayer on metal substrates. This close-packed monolayer could provide an excellent corrosion resistance for EG steel sheets. It was capable of withstanding 50˜60 hours of salt spray test (SST) although its thickness was only a few nanometers. The EG steel itself usually started rusting only after 2˜4 hours of salt spray. In another coating system, thiols were mixed with a conventional resin to improve the corrosion resistance of EG steel. This new technique gave 100˜120 hours of corrosion resistance. When the resin was applied directly on EG steel surface, its corrosion resistance was less than 72 hours. It was shown that further optimization of this technique increased the corrosion resistance to 200 hours and more in the standard SST.

  11. Ultrahigh carbon steels, Damascus steels, and superplasticity

    Energy Technology Data Exchange (ETDEWEB)

    Sherby, O.D. [Stanford Univ., CA (United States). Dept. of Materials Science and Engineering; Wadsworth, J. [Lawrence Livermore National Lab., CA (United States)

    1997-04-01

    The processing properties of ultrahigh carbon steels (UHCSs) have been studied at Stanford University over the past twenty years. These studies have shown that such steels (1 to 2.1% C) can be made superplastic at elevated temperature and can have remarkable mechanical properties at room temperature. It was the investigation of these UHCSs that eventually brought us to study the myths, magic, and metallurgy of ancient Damascus steels, which in fact, were also ultrahigh carbon steels. These steels were made in India as castings, known as wootz, possibly as far back as the time of Alexander the Great. The best swords are believed to have been forged in Persia from Indian wootz. This paper centers on recent work on superplastic UHCSs and on their relation to Damascus steels. 32 refs., 6 figs.

  12. EL ORO ES TRISTE

    Directory of Open Access Journals (Sweden)

    Jose María Corella Hurtado

    2012-01-01

    Full Text Available Esas narraciones eran las mismas cantaletas de mis abuelos, de mis tíos, de los negros y los mineros, contadas bajo las torrenciales noches de lluvia o bajo los indignos soles. Mi madre también relataba de memoria, como una cotorra y con la misma exactitud mientras realizaba los oficios domésticos, bien sean los de la barraca del puerto de Barbacoas o los de la casa de Pasto. Los barbacoanos de esa lejana generación, debieron soportar los recuerdos nefastos de la historia enquistada con dolor porque crecieron coreando episodios con la misma y sorprendente precisión. Era, es y será por siempre, una carcoma dolorosa y perseverante, aquello de la draga. Es que lo sucedido en Barbacoas no debe olvidarse y menos repetirse. Esos sucesos me comprometían de alguna manera; vividos unos en carne propia y a oídas otros que mezclaban el dolor que causó a los paisanos la pobreza en que quedaron.

  13. y la perdedora es...

    Directory of Open Access Journals (Sweden)

    Alejandro Ramos Escobedo

    2007-01-01

    Full Text Available El presente artículo aborda la relación entre la aplicación de la ley en el caso del divorcio por mutuo consentimiento, las diferencias de género y la justicia para la mujer de un sector popular de Guadalajara, Jalisco, México. Se describen testimonios de mujeres, abogados y jueces que muestran que en términos económicos y materiales la aplicación de la ley no necesariamente significa justicia para la mujer. Los testimonios presentados corresponden a la experiencia de mujeres, así como a abogados y jueces encargados de llevar los casos de divorcio. El artículo es producto del proyecto general acerca del estudio de la toma de decisiones en el divorcio.

  14. Testing and modelling of industrial tribo-systems for sheet metal forming

    DEFF Research Database (Denmark)

    Friis, Kasper Leth; Nielsen, Peter Søe; Bay, Niels

    2008-01-01

    Galling is a well-known problem in sheet metal forming of tribological difficult materials such as stainless steel. In this work new, environmentally friendly lubricants and wear resistant tool materials are tested in a laboratory environment using a strip reduction test as well as in a real...

  15. 75 FR 15741 - Sheet Metal Workers Internationl Association, Local 292: Troy, MI; Notice of Termination of...

    Science.gov (United States)

    2010-03-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Sheet Metal Workers Internationl Association, Local 292: Troy, MI... investigation was initiated in response to a petition filed on July 13, 2009 on behalf of workers of Steel Metal...

  16. Computational design of graphene sheets for withstanding the impact of ultrafast projectiles.

    Science.gov (United States)

    Sadeghzadeh, Sadegh

    2016-11-01

    A multi-scale method is employed in this paper to conduct a virtual study of the high-strain behavior of single- and multi-layer graphene sheets and to investigate the design of related graphene-based devices. By bridging the length and time scales by combining the Molecular Dynamics and Finite Element methods together, a comprehensive multiscale model is developed to study the fascinating capabilities of single- and multi-layer graphene sheets in withstanding the impact of ultrafast projectiles. In order to contribute to future developments and innovations in this field, several quantitative and qualitative comparisons are also performed. By employing the validated model, the effects of several parameters on the impact resistance efficiency of the examined sheets are evaluated. The specific penetration energy of multilayer graphene sheets is several times greater than that of metal sheets. It is demonstrated that the number of layers, aspect ratio, sheet size, interlayer distance, delamination, and projectile shape significantly influence the impact resistance of graphene sheets. The specific critical rupture velocity decreases asymptotically with the increase in the number of layers. A large-scale array of fewer graphene layers can withstand bullets of much higher velocities than a multilayer graphene sheet with equivalent weight. Finally, the coefficient of restitution for the oblique collision of gold and steel nanoparticles with multilayer graphene sheets is calculated at different impact velocities. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. El Futuro es Hoy

    Directory of Open Access Journals (Sweden)

    Alfonso Latiff Conde

    2002-08-01

    Full Text Available

    En ninguna otra época de la historia como en la nuestra se ha producido una transición tan rápida hacia el futuro, en el campo de la medicina.

    Lo que había sido una centuria de evolución desde la era Industrial a la era de la Informática, en la pasada década se ha convertido en una revolución.

    La cirugía laparoscopica que ha constituído el despertar a la edad de la informática como la tecnología lider es considerada ahora un standard en la práctica médica. En la actualidad tecnologias más avanzadas prometen mayores progresos en la medicina.

    La mayor revolución médica ocurrió en la cirugía en las postrimerias del siglo diecinueve cuando algunos gigantes de la medicina todavía caminaban sobre la tierra. Estos visionarios comprendieron la magnitud del cambio y dieron nacimiento a la nueva disciplina de la cirugía. Entre ellos estaban Bilroth, Lister, Virchow y Morton.

    Nunca trabajaron juntos, pero la integración espontánea de sus investigaciones y sus habilidades clínicas hicieron posible la nueva cirugía. Fue la convergencia de sus visiones y sus tecnologias las que dieron un vuelco a la cirugía. Bilroth aportó nuevas técnicas y nuevos instrumentos Lister aportó la asepsia, Virchow la patología y Morton la anestesia.

    Los antiguos mitos y muchos hechos empiricos hicieron creer por miles de años en la inviolabilidad del cuerpo humano. Las herramientas científicas de la Era Industrial convirtieron en realidad lo imposible y la ciencia dio nacimiento a la moderna cirugía. En un corto periodo de tiempo se establecieron los fundamentos de una cirugía que permitiría a las siguientes generaciones liderar nuevos avances y tecnologias.

    Nada estremeció más los fundamentos de la medicina como esta explosión de la cirugía. Comprender el shock, la cirugía cardiaca y coronaria, los trasplantes, tuvieron un enorme impacto que conmocionó la medicina. Es obvio que los cambios producidos

  18. Studies in Cup Drawing Behavior of Polymer Laminated Sheet Metal

    Science.gov (United States)

    Elnagmi, M.; Jain, M.; Bruhis, M.; Nielsen, K.

    2011-08-01

    Axisymmetric deep drawing behavior of a polymer laminated sheet metal (PLSM) is investigated using an axisymmetric cup drawing test. PLSMs are of interest as a replacement for painted finishes for automotive applications as they have the potential to achieve good quality long lasting and aesthetically appealing surfaces on stamped parts. However, there is limited understanding of PLSMs in automotive deep drawing situations to produce complex 3-D parts. The tests are carried out using well-controlled, laboratory-based, dual-action, servo-hydraulic forming presses under blank-holder force and punch displacement control conditions. An optical strain mapping system is used to measure the surface strains (and to construct 3D strain maps) from the film side of the deformed samples for a range of forming conditions. Deep drawing characteristics such as punch load versus punch displacement traces, strain distribution along the cup profile, flange wrinkling and fracture characteristics are experimentally assessed for stainless steel-plastic film laminated sheet materials. Also the effect of lamination pressure on wrinkling and delamination is investigated for a decorative pressure sensitive adhesive film affixed to the stainless steel sheet.

  19. Development of geometry of forming tools for extrusion of strip sheet by SPD process

    Science.gov (United States)

    Rusz, S.; Salajka, M.; Džugan, J.; Hilšer, O.; Bořuta, J.; Pastrňák, M.; Švec, J.

    2017-02-01

    On VSB -Technical University of Ostrava developed a method that uses the principle of severe plastic deformation to refine the structure and enhance mechanical properties of sheet metal strips. The greatest importance in practice represents an increase in yield strength and ultimate strength of sheet metal strips. The DRECE method (Dual Rolls Equal Channel Extrusion) is a newly developed method. Severe plastic deformation results in a high degree of the material deformation. The method can be used to produce metallic materials with a very fine grain structure. The paper analyses the effects of the values of angles of the newly developed forming tools on the achievement of mechanical properties in selected carbon steels by SPD process. The one type of steels (Ck55) was verified experimentally. Experiments were performed on the sheet metal strip with dimensions 58 (width) × 2 (thickness) × 1000 (length) mm with different inclination angle α.

  20. El sedentarismo es...

    Directory of Open Access Journals (Sweden)

    Alex Branco Fraga

    Full Text Available Resumen En este artículo se hizo un análisis crítico del sentido de sedentarismo/sedentario que circula en la literatura pertinente al campo de la actividad física y la salud. Destaca dos "familias" distintas de sedentarios surgidas en dos momentos históricos específicos: el sedentario "cooperiano", oriundo de los preceptos de la aptitud física difundidos en Brasil al principio de los años 1970 por Kenneth Cooper; el sedentario "agitoniano", proveniente de las recomendaciones de actividad física moderada de mediados de los años 1990, propagadas de modo más evidente en Brasil por el programa Agita São Paulo. Entre tantas acepciones posibles, prevalece la noción de que el sedentarismo es agente catalizador de muchas características "malas", una plaga silenciosa, que lentamente envenena el cuerpo y debilita el alma.

  1. The steel scrap age.

    Science.gov (United States)

    Pauliuk, Stefan; Milford, Rachel L; Müller, Daniel B; Allwood, Julian M

    2013-04-02

    Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age.

  2. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming Analysis, Simulation and Engineering Applications

    CERN Document Server

    Hu, Ping; Liu, Li-zhong; Zhu, Yi-guo

    2013-01-01

    Over the last 15 years, the application of innovative steel concepts in the automotive industry has increased steadily. Numerical simulation technology of hot forming of high-strength steel allows engineers to modify the formability of hot forming steel metals and to optimize die design schemes. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming focuses on hot and cold forming theories, numerical methods, relative simulation and experiment techniques for high-strength steel forming and die design in the automobile industry. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming introduces the general theories of cold forming, then expands upon advanced hot forming theories and simulation methods, including: • the forming process, • constitutive equations, • hot boundary constraint treatment, and • hot forming equipment and experiments. Various calculation methods of cold and hot forming, based on the authors’ experience in commercial CAE software f...

  3. Surface cracking in resistance seam welding of coated steels

    Energy Technology Data Exchange (ETDEWEB)

    Adonyi, Y.; Kimchi, M.

    1994-12-31

    In this experimental work, the focus was on the understanding the electrode-wheel/coated steel surface phenomena by building operational lobes and by correlating the weld quality with static-and dynamic-contact-resistance variation during welding. Conventional AC, DC, and electrode-wire resistance-seam weldability of printed zinc-coated and hot-dipped tin-coated steel was performed in this work, as compared with traditional lead-tin (terne) coating used as reference material. Variables included steel substrate type, welding equipment type, electrode-wheel cleaning practice, and electrode-wire geometry. Optic and electron microscopy were used for the evaluation of specimens extracted from longitudinal cross-sections of representative welds. The size and morphology of surface cracks was characterized and correlated with variations in the above-mentioned parameters. It was found that the tin-coated (unpainted) steel sheet had a superior all-together performance to the zinc-coated steel and terne-coated steel, both in terms of wider weldability lobes and lesser surface cracking. The extent of surface cracking was greatly reduced by using the electrode-wire seam welding process using a longitudinally grooved wire profile, which also widened the corresponding weldability lobes. It was also found that the extent of cracking depended on the electrode knurl geometry, substrate type, and the presence of conductive paint applied on top of the metallic coating. An attempt was made to characterize the specific mechanisms governing the LME phenomenon for the lead-, zinc and tin-based coating systems and to assess the potential for crack propagation in the welds. The dynamic contact resistance was found to be a good measure of the welding process stability and an indicator of defect formation. It was found that the ratio between the static and dynamic contact resistances of the tin-coated sheet was considerably lower than similar ratios for bare and zinc-coated sheet.

  4. New tribo-systems for sheet metal forming of advanced high strength steels and stainless steels

    DEFF Research Database (Denmark)

    Ceron, Ermanno

    Tribotester was developed. A production process was selected at Grundfos, which is currently running with chlorinated paraffin oil. The process includes a deep drawing and two subsequent re-drawings in a progressive tool. The process was numerically analyzed to investigate the tribological conditions...

  5. Photovoltaics Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-02-01

    This fact sheet is an overview of the Photovoltaics (PV) subprogram at the U.S. Department of Energy SunShot Initiative. The U.S. Department of Energy (DOE)’s Solar Energy Technologies Office works with industry, academia, national laboratories, and other government agencies to advance solar PV, which is the direct conversion of sunlight into electricity by a semiconductor, in support of the goals of the SunShot Initiative. SunShot supports research and development to aggressively advance PV technology by improving efficiency and reliability and lowering manufacturing costs. SunShot’s PV portfolio spans work from early-stage solar cell research through technology commercialization, including work on materials, processes, and device structure and characterization techniques.

  6. Soft Costs Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-05-01

    This fact sheet is an overview of the systems integration subprogram at the U.S. Department of Energy SunShot Initiative. Soft costs can vary significantly as a result of a fragmented energy marketplace. In the U.S., there are 18,000 jurisdictions and 3,000 utilities with different rules and regulations for how to go solar. The same solar equipment may vary widely in its final installation price due to process and market variations across jurisdictions, creating barriers to rapid industry growth. SunShot supports the development of innovative solutions that enable communities to build their local economies and establish clean energy initiatives that meet their needs, while at the same time creating sustainable solar market conditions.

  7. Influence of the surface quality due to a hole derived in initial material processing of cold sheets with drawing

    OpenAIRE

    Cvetkov, Slavco; Kocov, Atanas

    2010-01-01

    A research was performed about the influence of the surface quality due to a hole derived in initial material processing of cold-rolled steel sheets with drawing. This influence was researched through the surface quality obtained bu the type of preparation of the hole surface without prejudice to the precise measurement of the achieved quality (asperity). the aim is to indicate how the type of manufacturing the holes can improve the workability of cold-rolled sheets and help solve technical p...

  8. Development of sheet-metal parabolic-trough reflector panels

    Science.gov (United States)

    Biester, A. W.

    1982-06-01

    Efforts to develop accurate, durable, and mass producible sheet metal parabolic trough solar collectors and the associated support for the collectors are described. The design considered is similar to an automobile hood, a two-piece sheet metal structure consisting of a formed steel frame or stiffening panel and a smooth contoured skin. The two pieces may be bonded or welded to form a rigid structure, and a reflective surface applied such as a film, glass mirror, or any of the presently utilized materials. The work encompassed material selection, adhesive selection and testing, tool design and fabrication, prototype panel production, and design and development of torque tube assemblies on which the trough is inclined. Results of adhesive bonding studies are given. It is found that high volume technology can be used to produce accurate and structurally sound reflector panels, and one configuration was selected for fabrication in suitable quantities for performance testing.

  9. Microstructural characterization and simulation of damage for geared sheet components

    Science.gov (United States)

    Gerstein, G.; Isik, K.; Gutknecht, F.; Sieczkarek, P.; Ewert, J.; Tekkaya, A. E.; Clausmeyer, T.; Nürnberger, F.

    2017-09-01

    The evolution of damage in geared components manufactured from steel sheets was investigated, to analyse the influence of damage caused by the sheet-bulk-metal forming. Due to the inhomogeneous and multi-axial deformation in the investigated parts, different aspects such as the location-dependent shape and size of voids are analysed by means of various microscopic methods. In particular, a method to characterize the state of damage evolution, i. e. void nucleation, growth and coalescence using scanning electron microscopy (SEM) is applied. The investigations reveal a strong dependence of the void area fraction, shape of voids and thus damage evolution on the loading mode. The microstructural analysis is complemented with FEM simulations using material models which consider the characteristics of the void evolution.

  10. Metallographic problems of the production of parts from continuously cast high-speed steels

    Science.gov (United States)

    Supov, A. V.; Aleksandrova, N. M.; Paren'kov, S. A.; Kakabadze, R. V.; Pavlov, V. P.

    1998-09-01

    It has been assumed until recently that high-speed steels cannot be produced by the method of continuous casting. Numerous attempts to use this highly efficient technology for manufacturing such steels have failed because of breakage of the cast preforms. A solution was sought in improving the design of the continuous-casting machines (CCM), increasing the level of their automation, and using rational compositions of slag-forming mixtures (SFM). The idea was that a high-speed steel can be cast only in vertical CCM. The present work concerns regimes of secondary cooling under which the structures formed in high-speed steels provide a ductility sufficient for bending the continuously cast preform without failure. Steel R6M5 cast continuously in such a machine can easily be machined into hot-rolled preforms for sheets, wire, silver-steel rods, and other final products without a forging stage.

  11. Development of a low energy micro sheet forming machine

    Science.gov (United States)

    Razali, A. R.; Ann, C. T.; Shariff, H. M.; Kasim, N. I.; Musa, M. A.; Ahmad, A. F.

    2017-10-01

    It is expected that with the miniaturization of materials being processed, energy consumption is also being `miniaturized' proportionally. The focus of this study was to design a low energy micro-sheet-forming machine for thin sheet metal application and fabricate a low direct current powered micro-sheet-forming machine. A prototype of low energy system for a micro-sheet-forming machine which includes mechanical and electronic elements was developed. The machine was tested for its performance in terms of natural frequency, punching forces, punching speed and capability, energy consumption (single punch and frequency-time based). Based on the experiments, the machine can do 600 stroke per minute and the process is unaffected by the machine's natural frequency. It was also found that sub-Joule of power was required for a single stroke of punching/blanking process. Up to 100micron thick carbon steel shim was successfully tested and punched. It concludes that low power forming machine is feasible to be developed and be used to replace high powered machineries to form micro-products/parts.

  12. EFFECT OF MECHANICAL PROPERTIES OF MARTENSITE AND LOADING RATE ON DUAL PHASE STEELS

    Directory of Open Access Journals (Sweden)

    Ali BAYRAM

    1998-03-01

    Full Text Available In this study, steel sheet materials were used in order to obtain dual-phase steel. Specimens for this purpose have been annealed in ferrite + astatine regions at the temperatures of 740, 760, 800 and 820 °C. The specimens were annealed at the different temperatures with corresponding times 20, 40 and 60 minutes and quenched into water. As a result of this dual-phase steels at different ferrite + martensite ratio were produced. Sheet specimens were tested at the range of loading rates of 10, 50 and 259 mm/min. Strength properties of dual-phase steels were investigated depending on annealing temperature, ratio of martensite and loading rate.

  13. Vitamin and Mineral Supplement Fact Sheets

    Science.gov (United States)

    ... website Submit Search NIH Office of Dietary Supplements Vitamin and Mineral Supplement Fact Sheets Search the list ... Supplements: Background Information Botanical Dietary Supplements: Background Information Vitamin and Mineral Fact Sheets Botanical Supplement Fact Sheets ...

  14. Tool steels. 5. edition

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, G.; Krauss, G.; Kennedy, R.

    1998-12-31

    The revision of this authoritative work contains a significant amount of new information from the past nearly two decades presented in an entirely new outline, making this a must have reference for engineers involved in tool-steel production, as well as in the selection and use of tool steels in metalworking and other materials manufacturing industries. The chapter on tool-steel manufacturing includes new production processes, such as electroslag refining, vacuum arc remelting, spray deposition processes (Osprey and centrifugal spray), and powder metal processing. The seven chapters covering tool-steel types in the 4th Edition have been expanded to 11 chapters covering nine main groups of tool steels as well as other types of ultrahigh strength steels sometimes used for tooling. Each chapter discusses in detail processing, composition, and applications specific to the particular group. In addition, two chapters have been added covering surface modification and trouble shooting production and performance problems.

  15. Gap Bridging Ability in Laser GMA Hybrid Welding of Thin 22MnB5 Sheets

    Science.gov (United States)

    Möller, F.; Kügler, H.; Kötschau, S.; Geier, A.; Goecke, S.-F.

    In this paper, laser GMA hybrid welding of thin ultra-high-strength steel sheets (22MnB5) is investigated. A single-mode laser beam oscillating transversal to the welding direction is used in order to minimize the heat input during the process. The sheets have a thickness of 1.5mm each and are fixed in overlap configuration. The gap between the sheets was 0.8mm during experiments in order to simulate typical gap width in industrial manufacturing processes. It is shown that a stable weld seam has been achieved for this gap width in case of a welding speed of 6m/min. The gap bridging ability is caused by the interaction of the arc and the laser beam process. The laser beam process produces deeper penetration in the bottom sheet. Thus, the arc is stabilized by the laser beam.

  16. BORONIZING OF STEEL

    OpenAIRE

    ULUKÖY, Arzum; CAN, Ahmet Çetin

    2006-01-01

    Boride layer has many advantages in comparison with traditional hardening methods. The boride layer has high hardening value and keeps it's hardeness at high temperatures, and it also shows favorible properties, such as the resistance to wear, oxidation and corrosion. The process can be applied at variety of materials, for instance steel, cast iron, cast steel, nickel and cobalt alloys and cermets. In this rewiew, boronizing process properties, boride layer on steel surfaces and specification...

  17. Retained austenite variation in dual-phase steel after mechanical stressing and heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Giordano, L.; Tiziani, A.; Zambon, A. (Dipt. di Innovazione Meccanica e Gestionale, Padua Univ. (Italy)); Matteazzi, P. (Ist. di Chimica, Univ. di Udine (Italy))

    1991-01-20

    Retained austenite changes in a dual-phase steel have been studied after mechanical and thermal treatments. In order to determine the quantitative variations of retained austenite, whose amount in the examined steel is of the order of 5%, Moessbauer spectroscopy has been used. Retained austenite undergoes a martensitic transformation during deformation, but does not transform under the heat treatments performed on the sheet during anticorrosion and painting processes. (orig.).

  18. Laboratory Investigation of Skid Resistance for Steel Slag Utilization as Chip Seal

    OpenAIRE

    Fitria Hidayatiningrum, Laely; Budi Suparma, Latif

    2011-01-01

    Slag as waste material of steel-making process has similar characteristics with aggregate that has been widely used in pavement construction. The use of slag as chip seal aggregate to provide skid resistance needs to be analyzed. In this laboratory study, the chip seal samples are made using steel slag and natural aggregate. The bonding materials used are asphalt and epoxy resin. Skid resistance tests for all chip seal samples and also hot rolled sheet pavement without chip seal application a...

  19. Electromagnetic NDT to characterize usage properties of flat steel products - Part 3

    Energy Technology Data Exchange (ETDEWEB)

    Altpeter, I.; Dobmann, G.; Szielasko, K., E-mail: iab.altlau@t-online.de, E-mail: gerd.dobmann@t-online.de, E-mail: klaus.szielasko@izfp.fraunhofer.de [Fraunhofer Inst. - IZFP, Saarbruecken (Germany)

    2015-11-15

    The Fraunhofer Institute for Nondestructive Testing (IZFP) in Saarbruecken, Germany, started its activities in materials characterization of flat steel products in the eighties of the last century in the basic program of the European Community of Coal and Steel (ECCS). Throughout the years, continuous research and development were performed. The objective of the work, presented within this three-part series of reports, is to discuss the history of an innovation that began in 1988 with R&D in the area of texture characterization in steel sheets produced for car-body manufacturing (Part 1). In the following years the activities were to automate online property determination in terms of yield strength, tensile strength, planar- and vertical-anisotropy factors. Again, steel sheets were the focus of the developments and first NDT systems came into industrial application. Parallel research was performed to characterize the mechanical properties and hardness on heavy steel plates, mainly produced for pipeline manufacturing and offshore applications (Part 2). The final report in the series (Part 3) discusses steel sheet characterization and presents the successful development of a combination transducer that combines ultrasonics with electromagnetic NDT. (author)

  20. Atmospheric corrosion of mild steel

    Directory of Open Access Journals (Sweden)

    Morcillo, M.

    2011-10-01

    Full Text Available The atmospheric corrosion of mild steel is an extensive topic that has been studied by many authors in different regions throughout the world. This compilation paper incorporates relevant publications on the subject, in particular about the nature of atmospheric corrosion products, mechanisms of atmospheric corrosion and kinetics of the atmospheric corrosion process, paying special attention to two matters upon which relatively less information has been published: a the morphology of steel corrosion products and corrosion product layers; and b long-term atmospheric corrosion ( > 10 years.

    La corrosión atmosférica del acero suave es un tema de gran amplitud que ha sido tratado por muchos autores en numerosas regiones del mundo. Este artículo de compilación incorpora publicaciones relevantes sobre esta temática, en particular sobre la naturaleza de los productos de corrosión atmosférica, mecanismos y cinética de los procesos de corrosión atmosférica, prestando una atención especial a dos aspectos sobre los que la información publicada ha sido menos abundante: a morfología de los productos de corrosión del acero y capas de productos de corrosión, y b corrosión atmosférica a larga duración (> 10 años.

  1. State Fact Sheets on COPD

    Science.gov (United States)

    ... Submit Search The CDC Chronic Obstructive Pulmonary Disease (COPD) Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . COPD Homepage Data and Statistics Fact Sheets Publications Publications ...

  2. 2008 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  3. 2010 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  4. 2009 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  5. 2007 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  6. 2006 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  7. Modelling the Antarctic Ice Sheet

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke; Holm, A.

    2015-01-01

    The Antarctic ice sheet is a major player in the Earth’s climate system and is by far the largest depository of fresh water on the planet. Ice stored in the Antarctic ice sheet (AIS) contains enough water to raise sea level by about 58 m, and ice loss from Antarctica contributed significantly...... to sea level high stands during past interglacial periods. A number of AIS models have been developed and applied to try to understand the workings of the AIS and to form a robust basis for future projections of the AIS contribution to sea level change. The recent DCESS (Danish Center for Earth System...... Science) Antarctic Ice Sheet (DAIS) model (Shaffer 2014) is forced by reconstructed time series of Antarctic temperature, global sea level and ocean subsurface temperature over the last two glacial cycles. In this talk a modelling work of the Antarctic ice sheet over most of the Cenozoic era using...

  8. Industrial Stormwater Fact Sheet Series

    Science.gov (United States)

    Fact sheets for the industrial sectors regulated by the MSGP. Each describes the types of facilities included in the sector, typical pollutants associated with the sector, and types of stormwater control measures used to minimize pollutant discharge.

  9. Theoretical analysis of sheet metal formability

    Science.gov (United States)

    Zhu, Xinhai

    Sheet metal forming processes are among the most important metal-working operations. These processes account for a sizable proportion of manufactured goods made in industrialized countries each year. Furthermore, to reduce the cost and increase the performance of manufactured products, in addition to the environmental concern, more and more light weight and high strength materials have been used as a substitute to the conventional steel. These materials usually have limited formability, thus, a thorough understanding of the deformation processes and the factors limiting the forming of sound parts is important, not only from a scientific or engineering viewpoint, but also from an economic point of view. An extensive review of previous studies pertaining to theoretical analyses of Forming Limit Diagrams (FLDs) is contained in Chapter I. A numerical model to analyze the neck evolution process is outlined in Chapter II. With the use of strain gradient theory, the effect of initial defect profile on the necking process is analyzed. In the third chapter, the method proposed by Storen and Rice is adopted to analyze the initiation of localized neck and predict the corresponding FLDs. In view of the fact that the width of the localized neck is narrow, the deformation inside the neck region is constrained by the material in the neighboring homogeneous region. The relative rotation effect may then be assumed to be small and is thus neglected. In Chapter IV, Hill's 1948 yield criterion and strain gradient theory are employed to obtain FLDs, for planar anisotropic sheet materials by using bifurcation analysis. The effects of the strain gradient coefficient c and the material anisotropic parameters R's on the orientation of the neck and FLDs are analyzed in a systematic manner and compared with experiments. In Chapter V, Hill's 79 non-quadratic yield criterion with a deformation theory of plasticity is used along with bifurcation analyses to derive a general analytical

  10. Development of oil canning index model for sheet metal forming products with large curvature

    Science.gov (United States)

    Kim, Honglae; Lee, Seonggi; Murugesan, Mohanraj; Hong, Seokmoo; Lee, Shanghun; Ki, Juncheol; Jung, Hunchul; Kim, Naksoo

    2017-09-01

    Oil canning is predominantly caused by unequal stretches and heterogeneous stress distributions in steel sheets, which affects the appearance of components and develop noise and vibration problems. This paper proposes the formulation of an Oil canning index (OCI) model that can predict the occurrence of oil canning in the sheet metal. To investigate the influence of material properties, we used electro-galvanized (EGI) and galvanized (GI) steel sheets with different thicknesses and processing conditions. Furthermore, this paper presents an appropriate experimental and numerical procedure for determining the sheet stiffness and indentation properties to evaluate the oil canning results. Experiments were carried out by varying the tensile force over different materials, thicknesses, and bead force. Comparison of the discrete results obtained from these experiments confirmed that the product shape characteristics, such as curvature, have a significant influence on the oil canning occurrence. Based on the results, we propose the new OCI model, which can effectively predict the oil canning occurrence owing to the shape curvature. Verification of the accuracy and usability of our model has been carried out by simulating the experiments that were done with the sheet metal. The authors observed a good agreement between the experimental and numerical results from the model. This research work can be considered as a very effective method for eliminating appearance defects from the automobile products.

  11. Energy information sheets, July 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  12. Flow visualization by laser sheet

    OpenAIRE

    Chlebanowski, Joseph S., Jr.

    1988-01-01

    Approved for public release; distribution is unlimited. A flow visualization system using smoke and a laser sheet for illumination has been designed and developed for use in the 32- x 45-inch low speed wind tunnel. Major design features include a portable smoke rake designed for ease of installation and removal, the use of fiber optics to transport the laser light in a safe and convenient manner, and a portable traversing mechanism to traverse and orient the laser light sheet. The capabili...

  13. Modern Steel Framed Schools.

    Science.gov (United States)

    American Inst. of Steel Construction, Inc., New York, NY.

    In view of the cost of structural framing for school buildings, ten steel-framed schools are examined to review the economical advantages of steel for school construction. These schools do not resemble each other in size, shape, arrangement or unit cost; some are original in concept and architecture, and others are conservative. Cost and…

  14. FDTD modeling of thin impedance sheets

    Science.gov (United States)

    Luebbers, Raymond J.; Kunz, Karl S.

    1991-01-01

    Thin sheets of resistive or dielectric material are commonly encountered in radar cross section calculations. Analysis of such sheets is simplified by using sheet impedances. In this paper it is shown that sheet impedances can be modeled easily and accurately using Finite Difference Time Domain (FDTD) methods.

  15. Influence of Surface Tension and Surface Shear on Final Coat Thickness in Jet-Stripped Continuous Coating of Sheet Materials.

    Science.gov (United States)

    1983-11-01

    galvanising industry, this pressure distribution is created by blowing a thin high-speed air jet onto the coated steel sheet, just after it emerges from the...if that free surface possesses curvature and non-zero surface tension, the internal pressure will differ from that in the jet. In the galvanising

  16. Vision-based surface defect inspection for thick steel plates

    Science.gov (United States)

    Yun, Jong Pil; Kim, Dongseob; Kim, KyuHwan; Lee, Sang Jun; Park, Chang Hyun; Kim, Sang Woo

    2017-05-01

    There are several types of steel products, such as wire rods, cold-rolled coils, hot-rolled coils, thick plates, and electrical sheets. Surface stains on cold-rolled coils are considered defects. However, surface stains on thick plates are not considered defects. A conventional optical structure is composed of a camera and lighting module. A defect inspection system that uses a dual lighting structure to distinguish uneven defects and color changes by surface noise is proposed. In addition, an image processing algorithm that can be used to detect defects is presented in this paper. The algorithm consists of a Gabor filter that detects the switching pattern and employs the binarization method to extract the shape of the defect. The optics module and detection algorithm optimized using a simulator were installed at a real plant, and the experimental results conducted on thick steel plate images obtained from the steel production line show the effectiveness of the proposed method.

  17. Adhesiveness of cold rolled steels for car body parts

    Directory of Open Access Journals (Sweden)

    Kleiner Marques Marra

    2007-09-01

    Full Text Available The aim of this work was to evaluate the adhesiveness of uncoated and zinc-electrogalvanized steel sheets used in the automotive industry. Three types of adhesives, one acrylic and two epoxy resins, were employed to join low carbon cold rolled steels, one uncoated and another electrogalvanized, both previously degreased or chemically pickled. Mechanical strength of the joints was evaluated by the T-peel and tensile strength tests. Steel grade, surface condition and heating below the cure temperatures did not influence the joints' mechanical strength. However, their shear strength decreased drastically as the test temperature increased. The exposure of the joints to an atmosphere with 90% relative humidity at 40 °C caused reduction of their shear strength. Epoxy adhesives showed higher mechanical strength, but exhibited higher degradation by humidity.

  18. Hyperplasticity effect under magnetic pulse straightening of dual phase steel

    Science.gov (United States)

    Falaleev, AP; Meshkov, VV; Shymchenko, A.

    2016-10-01

    An investigation of the behaviour of dual phase steel parts during straightening operations, by means of magnetic pulse treatment, is presented. The mechanical analysis of magnetic-pulse treatment for the straightening of thin-walled sheet metal parts produced from dual phase steel was performed, taking into account the effect of hyperplasticity under the influence of the magnetic field. Taking account of the causes of the hyperplasticity and thus the increase of material plasticity, it has been shown that the magnetic impulse gravity can be adjusted by controlling the operation modes. The dependence of the generated magnetic impulse gravity force on the electrical current strength inducted in this part was explored and used for analysis of the magnetic pulse straightening of dual phase steel part. Experimental results were obtained for thin-walled sheet metal part produced from dual phase steel DP 780. The results are used to demonstrate the material deformation under the influence of magnetic impulse gravity force considering the increase of material plasticity. The dependence of relative material deformation on the generated magnetic impulse gravity as well as on the current strength induced in this material was obtained and analyzed

  19. Standard test method for electrochemical critical pitting temperature testing of stainless steels

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 This test method covers a procedure for the evaluation of the resistance of stainless steel and related alloys to pitting corrosion based on the concept of the determination of a potential independent critical pitting temperature (CPT). 1.2 This test methods applies to wrought and cast products including but not restricted to plate, sheet, tubing, bar, forgings, and welds, (see Note 1). Note 1—Examples of CPT measurements on sheet, plate, tubing, and welded specimens for various stainless steels can be found in Ref (1). See the research reports (Section 14). 1.3 The standard parameters recommended in this test method are suitable for characterizing the CPT of austenitic stainless steels and other related alloys with a corrosion resistance ranging from that corresponding to solution annealed UNS S31600 (Type 316 stainless steel) to solution annealed UNS S31254 (6 % Mo stainless steel). 1.4 This test method may be extended to stainless steels and other alloys related to stainless steel that have a CPT...

  20. es

    Directory of Open Access Journals (Sweden)

    Esther Bernal Valls

    Full Text Available El uso de ejercicios en el tratamiento de pacientes con déficit vestibular crónico está incrementándose de forma notable, lo que evidencia que se trata de un procedimiento que resulta beneficioso para este tipo de pacientes. Los buenos resultados que se obtienen sugieren que los ejercicios vestibulares dan lugar a una estabilidad postural y a una disminución de la sensación de desequilibrio.

  1. Automobile sheet metal part production with incremental sheet forming

    Directory of Open Access Journals (Sweden)

    İsmail DURGUN

    2016-02-01

    Full Text Available Nowadays, effect of global warming is increasing drastically so it leads to increased interest on energy efficiency and sustainable production methods. As a result of adverse conditions, national and international project platforms, OEMs (Original Equipment Manufacturers, SMEs (Small and Mid-size Manufacturers perform many studies or improve existing methodologies in scope of advanced manufacturing techniques. In this study, advanced manufacturing and sustainable production method "Incremental Sheet Metal Forming (ISF" was used for sheet metal forming process. A vehicle fender was manufactured with or without die by using different toolpath strategies and die sets. At the end of the study, Results have been investigated under the influence of method and parameters used.Keywords: Template incremental sheet metal, Metal forming

  2. Horizontal electromagnetic casting of thin metal sheets

    Science.gov (United States)

    Hull, John R.; Lari, Robert J.; Praeg, Walter F.; Turner, Larry R.

    1987-01-01

    Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

  3. Horizontal electromagnetic casting of thin metal sheets

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

    1988-01-01

    Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

  4. Strengthening of RC bridge slabs using CFRP sheets

    Directory of Open Access Journals (Sweden)

    Fahmy A. Fathelbab

    2014-12-01

    Full Text Available Many old structures became structurally insufficient to carry the new loading conditions requirements. Moreover, they suffer from structural degradation, reinforcement steel bars corrosion, bad weather conditions…etc. Many official authorities in several countries had recognized many old bridges and buildings as structurally deficient by today’s standards. Due to these reasons, structural strengthening became an essential requirement and different strengthening techniques appeared in market. Fiber Reinforced Polymer (FRP strengthening techniques established a good position among all other techniques, giving excellent structural results, low time required and moderate cost compared with the other techniques. The main purpose of this research is to study analytically the strengthening of a reinforced concrete bridge slabs due to excessive loads, using externally bonded FRP sheets technique. A commercial finite element program ANSYS was used to perform a structural linear and non-linear analysis for strengthened slab models using several schemes of FRP sheets. A parametric study was performed to evaluate analytically the effect of changing both FRP stiffness and FRP schemes in strengthening RC slabs. Comparing the results with control slab (reinforced concrete slab without strengthening it is obvious that attaching FRP sheets to the RC slab increases its capacity and enhances the ductility/toughness.

  5. BORONIZING OF STEEL

    Directory of Open Access Journals (Sweden)

    Arzum ULUKÖY

    2006-02-01

    Full Text Available Boride layer has many advantages in comparison with traditional hardening methods. The boride layer has high hardening value and keeps it's hardeness at high temperatures, and it also shows favorible properties, such as the resistance to wear, oxidation and corrosion. The process can be applied at variety of materials, for instance steel, cast iron, cast steel, nickel and cobalt alloys and cermets. In this rewiew, boronizing process properties, boride layer on steel surfaces and specifications and the factors that effect boride layer are examined

  6. Sulfate-reducing bacteria inhabiting natural corrosion depostis from marine steel structures

    NARCIS (Netherlands)

    Païssé, S.; Ghiglione, J.-F.; Marty, F.; Abbas, B.; Gueuné, H.; Sanchez Amaya, J.; Muyzer, G.; Quillet, L.

    2013-01-01

    In the present study, investigations were conducted on natural corrosion deposits to better understand the role of sulfate-reducing bacteria (SRB) in the accelerated corrosion process of carbon steel sheet piles in port environments. We describe the abundance and diversity of total and metabolically

  7. Constitutive modeling of quench-hardenable boron steel with tailored properties

    NARCIS (Netherlands)

    Eller, Tom; Greve, L; Anders, M.T.; Medricky, M; Hatscher, A; Meinders, Vincent T.; van den Boogaard, Antonius H.; Volk, W.

    2013-01-01

    In this work, a material model is presented that predicts the crash-relevant constitutive behavior of quench-hardenable boron steel 22MnB5 as function of material hardness. Three sets of sheets of 22MnB5 are heat treated such that their as-treated microstructures are close to fully martensitic,

  8. Quantification of Galling in Sheet Metal Forming by surface topography characterisation

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Bay, Niels; De Chiffre, Leonardo

    1998-01-01

    One of the major problems in forming of stainless steel sheet is galling due to lubricant film breakdown leading to scoring and bad surface quality. In a Danish research programme new lubricants substituting the normally applied chlorinated paraffin oils are being developed and tested for this pu...... reduction test, this is done by 2D profilometry at strip locations corresponding to different sliding lengths, whereas a deep drawing test is based on 3D roughness mapping of local areas....

  9. Comparison between strong η-fiber-oriented high-silicon steel and grain-oriented high-silicon steel on magnetic properties

    Science.gov (United States)

    Qin, Jing; Yue, Ye; Zhang, Yinghui; Cao, Yanyan; Yang, Ping

    2017-10-01

    Two kinds of 0.23 mm-thick high-silicon steel sheets with strong η-fiber texture and Goss texture were produced by rolling methods. Their final microstructures, textures and magnetic properties were analyzed by scanning electron microscope (SEM), transmission electron microscope (TEM), energy-dispersive spectroscopy (EDS), X-ray diffractometer (XRD), electron backscattered diffraction (EBSD) and classical loss separation. The results showed that the core loss of strong η-fiber-oriented high-silicon steel was lower than that of grain-oriented high-silicon steel at frequencies ranging from 40 Hz to 20 kHz, and their differences in core loss were more obvious at 400 Hz and higher frequencies. The hysteresis losses and anomalous losses of the strong η-fiber-oriented high-silicon steel were lower than that of grain-oriented high-silicon steel at frequencies ranging from 40 Hz to 1000 Hz, and the losses were closely related to final cleanness and grain sizes. A few stable remained nitride precipitates increased the hysteresis loss of the grain-oriented high-silicon steel. The effect of decreasing grain sizes on decreasing core losses at high frequencies was significant, and the strong η-fiber-oriented high-silicon steel was more suitable for high frequency applications because of smaller grain sizes compared to the grain-oriented high-silicon steel.

  10. Philippe Lebrun, Head of the AT Department, Lyn Evans, LHC Project Leader, and Lucio Rossi, Head of the AT-MAS Group, in front of the last batch of steel for the LHC at Cockerill Sambre.

    CERN Multimedia

    2005-01-01

    Casting the last batch of steel sheets for the LHC superconducting magnet yokes. The yokes constitute approximately 80% of the accelerator's weight and, if placed side by side, would stretch over 20 km !

  11. Sepúlveda es arte

    OpenAIRE

    García Poza, Almudena

    2017-01-01

    Uno de los principales contenidos en la formación y educación de los niños, es el conocimiento de su pasado más cercano. Partiendo de esta idea fundamental es casi una exigencia como docentes, ofrecer a los alumnos los contenidos y las herramientas necesarias para que conozcan su pasado histórico y las manifestaciones artísticas que expresaron su cultura. Conocer, comprender y valorar nuestro pasado va a convertir la práctica educativa en un aprendizaje empírico donde los conocimientos tengan...

  12. Glass Stronger than Steel

    Science.gov (United States)

    Yarris, Lynn

    2011-03-28

    A new type of damage-tolerant metallic glass, demonstrating a strength and toughness beyond that of steel or any other known material, has been developed and tested by a collaboration of researchers from Berkeley Lab and Caltech.

  13. Metallurgy: Printing steels

    Science.gov (United States)

    Todd, Iain

    2018-01-01

    Additive manufacturing has been used to fabricate a common stainless steel, which imparts a unique microstructure to this material, making it stronger and more ductile than that produced with conventional methods.

  14. Ice sheet hydrology - a review

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter; Naeslund, Jens-Ove [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden); Rodhe, Lars [Geological Survey of Sweden, Uppsala (Sweden)

    2007-03-15

    This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

  15. Hydrogeological map of Kabo Sheet 80NW topographical sheet 1 ...

    African Journals Online (AJOL)

    A hydro geological mapping of the Federal Surveys of Nigeria, Kabo Sheet 80 NW, on scale 1:50,000 were made with areal coverage of 729Km2 on the Crystalline Basement Complex, and the hydrogeoogical maps produced are maps of depth to the water table and maps of configuration peak of dry season and wet ...

  16. hydrogeological map of kabo sheet 80 nw topographical sheet 1

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. A hydro geological mapping of the Federal Surveys of Nigeria, Kabo Sheet 80 NW, on scale 1:50,000 were made with areal coverage of 729Km2 on the Crystalline Basement Complex, and the hydrogeoogical maps produced are maps of depth to the water table and maps of configuration peak of dry season ...

  17. Life after Steel

    Science.gov (United States)

    Mangan, Katherine

    2013-01-01

    Bobby Curran grew up in a working-class neighborhood in Baltimore, finished high school, and followed his grandfather's steel-toed bootprints straight to Sparrows Point, a 3,000-acre sprawl of industry on the Chesapeake Bay. College was not part of the plan. A gritty but well-paying job at the RG Steel plant was Mr. Curran's ticket to a secure…

  18. Peeling behavior and spalling resistance of CFRP sheets bonded to bent concrete surfaces

    Science.gov (United States)

    Yuan, Hong; Li, Faping

    2010-05-01

    In this paper, the peeling behavior and the spalling resistance effect of carbon fiber reinforced polymer (CFRP) sheets externally bonded to bent concrete surfaces are firstly investigated experimentally. Twenty one curved specimens and seven plane specimens are studied in the paper, in which curved specimens with bonded CFRP sheets can simulate the concrete spalling in tunnel, culvert, arch bridge etc., whereas plane specimens with bonded CFRP sheets can simulate the concrete spalling in beam bridge, slab bridge and pedestrian bridge. Three kinds of curved specimens with different radii of curvature are chosen by referring to practical tunnel structures, and plane specimens are used for comparison with curved ones. A peeling load is applied on the FRP sheet by loading a circular steel tube placed into the central notch of beam to debond CFRP sheets from the bent concrete surface, meanwhile full-range load-deflection curves are recorded by a MTS 831.10 Elastomer Test System. Based on the experimental results, a theoretical analysis is also conducted for the specimens. Both theoretical and experimental results show that only two material parameters, the interfacial fracture energy of CFRP-concrete interface and the tensile stiffness of CFRP sheets, are needed for describing the interfacial spalling behavior. It is found that the radius of curvature has remarkable influence on peeling load-deflection curves. The test methods and test results given in the paper are helpful and available for reference to the designer of tunnel strengthening.

  19. Microstructural alterations associated with friction drilling of steel, aluminum, and titanium

    Science.gov (United States)

    Miller, Scott F.; Shih, Albert J.; Blau, Peter J.

    2005-10-01

    Friction drilling, also called thermal drilling, is a novel sheet metal hole-making process. The process involves forcing a rotating, pointed tool through a sheet metal workpiece. The frictional heating at the interface between the tool and workpiece enables the softening, deformation, and displacement of work-material and creates a bushing surrounding the hole without generating chip or waste material. The bushing can be threaded and provides the structural support for joining devices to the sheet metal. The research characterizes the microstructures and indentation hardness changes in the friction drilling of carbon steel, alloy steel, aluminum, and titanium. It is shown that materials with different compositions and thermal properties affect the selection of friction drilling process parameters, the surface morphology of the bore, and the development of a highly deformed layer adjacent to the bore surface.

  20. Microstructural Alterations Associated with Friction Drilling of Steel, Aluminum, and Titanium*

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Scott F [ORNL; Blau, Peter Julian [ORNL; Shih, Albert J. [University of Michigan

    2005-01-01

    Friction drilling, also called thermal drilling, is a novel sheet metal hole-making process. The process involves forcing a rotating, pointed tool through a sheet metal workpiece. The frictional heating at the interface between the tool and workpiece enables the softening, deformation, and displacement of work-material and creates a bushing surrounding the hole without generating chip or waste material. The bushing can be threaded and provides the structural support for joining devices to the sheet metal. The research characterizes the microstructures and indentation hardness changes in the friction drilling of carbon steel, alloy steel, aluminum, and titanium. It is shown that materials with different compositions and thermal properties affect the selection of friction drilling process parameters, the surface morphology of the bore, and the development of a highly deformed layer adjacent to the bore surface.

  1. Los manatíes

    OpenAIRE

    2000-01-01

    Los manatíes pueden vivir en ríos de aguas tranquilas, canales, en bahías de agua salada y en el océano. El manatí de las Indias Occidentales, llamado científicamente Trichechus manatus, habita en la cuenca del Caribe, desde la Florida hasta Brasil.

  2. Colombia es una cosa penetrable

    Directory of Open Access Journals (Sweden)

    Gilberto Loaiza Cano

    2007-10-01

    Full Text Available Colombia es una cosa impenetrable. Raíces de la intolerancia y otros ensayos sobre historia política y vida intelectual. Juan Guillermo Gómez García. Bogotá, Diente de León, 2006, 454 pág.

  3. Steel skin - SMC laminate structures for lightweight automotive manufacturing

    Science.gov (United States)

    Quagliato, Luca; Jang, Changsoon; Murugesan, Mohanraj; Kim, Naksoo

    2017-09-01

    In the present research work an innovative material, made of steel skin and sheet molding compound core, is presented and is aimed to be utilized for the production of automotive body frames. For a precise description of the laminate structure, the material properties of all the components, including the adhesive utilized as an interlayer, have been carried out, along with the simple tension test of the composite material. The result have shown that the proposed laminate structure has a specific yield strength 114% higher than 6061 T6 aluminum, 34% higher than 7075 T6 aluminum, 186% higher than AISI 304 stainless steel (30HRC) and 42% than SK5 high-strength steel (52HRC), showing its reliability and convenience for the realization of automotive components. After calibrating the material properties of the laminate structure, and utilizing as reference the simple tension results of the laminate structure, the derived material properties have been utilized for the simulation of the mechanical behavior of an automotive B-pillar. The results have been compared with those of a standard B-pillar made of steel, showing that the MS-SMC laminate structure manifests load and impact carry capacity comparable with those of high strength steel, while granting, at least, an 11% weight reduction.

  4. Parametric Study of Open Trough Steel Concrete Composite Deck

    Directory of Open Access Journals (Sweden)

    Merool Devarsh Vakil

    2015-01-01

    Full Text Available Steel concrete composite deck is used in many parts of the world as fast and economical structural system. Recently the techniques are getting attention in India also. The profile deck is made up of thin cold formed steel sheet which can be formed in any desired shape. In this paper, critical study is made by varying the geometrical and material strength parameters of steel concrete deck. Its effect on flexural resistance and neutral axis location is analyzed. Ductile behavior of deck is another important concern. Here, authors put forward the limiting value of neutral axis for commonly used grades of steel for profile deck, which should be checked to ensure ductile behavior of composite deck. The paper considers variations in concrete thickness, yield strength of material, cylinder strength of concrete for an open trough type profile deck .Analysis of moment of resistance and depth of neutral axis are made as per Euro code EN-1994 assuming full bond between steel and concrete. The results show that there is significant variation in flexural capacity and neutral axis location on varying geometrical and material parameters.

  5. Comparação entre o fio de náilon e o fio de aço na imobilização de fraturas patelares induzidas em cães A comparison between a nylon thread and steel thread on the immobilization of experimentally patellar fractures in dogs

    Directory of Open Access Journals (Sweden)

    Ricardo Junqueira Del Carlo

    1998-03-01

    Full Text Available Foi realizado estudo comparativo entre o fio de náilon e o fio de aço, na imobilização das fraturas patelares induzidas em quatorze cadelas, sem raça definida, adultas, separadas em dois grupos iguais denominados grupos I e II. Em ambos os grupos a patela foi fraturada transversalmente e transfixada com broca por onde foi colocada a primeira sutura. Um segundo fio foi passado em forma de "x" sobre a patela, funcionando como banda de tensão. No grupo I foi utilizado fio de náilon para pesca número 0,60, e no grupo II o fio de aço ortopédico número 2. A melhora clínica dos animais, independentemente do tipo de fio utilizado, foi diretamente relacionada ao tempo pós-operatório. O fio de náilon, além de ser mais facilmente maneável, foi capaz de manter os fragmentos ósseos alinhados e aproximados. O fio de aço não foi capaz de realizar a função de banda de tensão, pois rompeu em todos os animais.Fourteen female dogs, without a definite breed, were divided into two similar experimental groups, denominated Group I and Group II which were submitted to a comparativo study between a nylon thread and steel thread, respectively, on the immobilization of experimentally patellar fractures in dogs. Dogs of each group were submitted a only surgical procedure. All animals were evaluated during a period of 45 days when the feasibility of the nylon thread on the immobilization of the patellar fractures was observed to be successful in comparison to the steel thread, that even though it is highly recommended on the situations in which the material might be up to a distention and alternated relaxing, for under such conditions, the thread will quickly suffer fatigue, consequently breaking up.

  6. COMPUTER CONTROLLED EXPERIMENTAL DEVICE FOR INVESTIGATIONS OF TRIBOLOGICAL INFLUENCES IN SHEET METAL FORMING

    Directory of Open Access Journals (Sweden)

    Tomislav Vujinović

    2012-05-01

    Full Text Available Sheet metal forming, especially deep drawing process is influenced by many factors. Blank holding force and drawbead displacement are two of them that can be controlled during the forming process.For this purpose, an electro-hydraulic computerized sheet-metal strip sliding device has been constructed. The basic characteristic of this device is realization of variable contact pressure and drawbead height as functions of time or stripe displacement. There are both, pressure and drawbead, ten linear and nonlinear functions. Additional features consist of the ability to measure drawing force, contact pressure, drawbead displacement etc.The device overview and first results of steel sheet stripe sliding over rounded drawbead are presented in the paper.

  7. Computer controlled experimental device for investigations of tribological influences in sheet metal forming

    Directory of Open Access Journals (Sweden)

    Milan Djordjevic

    2012-05-01

    Full Text Available Sheet metal forming, especially deep drawing process, is influenced by many factors. Blank holding force and drawbead displacement are two of them that can be controlled during the forming process. For this purpose, electro-hydraulic computerized sheet-metal strip sliding device has been constructed. Basic characteristic of this device is realization of variable contact pressure and drawbead height as functions of time or stripe displacement. There are both, pressure and drawbead, ten linear and nonlinear functions. Additional features consist of the ability to measure drawing force, contact pressure, drawbead displacement etc. Presented in the paper are the device overview and the first results of steel sheet stripe sliding over rounded  drawbead.

  8. High Blood Pressure Fact Sheet

    Science.gov (United States)

    ... High Blood Pressure Salt Cholesterol Million Hearts® WISEWOMAN High Blood Pressure Fact Sheet Language: English (US) Español (Spanish) Recommend ... time. High blood pressure is also called hypertension. High Blood Pressure in the United States Having high blood pressure ...

  9. Higher Education Act. Fact Sheet.

    Science.gov (United States)

    National Council on Disability, 2004

    2004-01-01

    This fact sheet highlights the challenges for students with disabilities in the nation's university system and recommends solutions that would result in better support systems for postsecondary students with disabilities. This document discusses several interrelated issues that impact student preparation and access to postsecondary education. The…

  10. Application of Incremental Sheet Forming

    Directory of Open Access Journals (Sweden)

    Karbowski Krzysztof

    2015-12-01

    Full Text Available This paper describes some manufacturing aspects and an example of application of the Incremental Sheet Forming (ISF technology which was used for production of the craniofacial prosthesis. The brief description of prosthesis designing was presented as well. The main topic of the paper is comparison of milling and ISF technologies for preparing the tools for prosthesis thermoforming.

  11. Impact of Steel Fiber Size and Shape on the Mechanical Properties of Ultra-High Performance Concrete

    Science.gov (United States)

    2015-08-01

    DATA SHEET OL 10/.20 What is Dramix8? Dramix- steel fibres , from industry specialist Bekaert, have set a new standard for concrete reinforcement with...characteristics of steel fiber reinforcement to the mechanical properties of high-strength concretes , this study investigated four commercially available...Standard test method for flexural performance of fiber- reinforced concrete (using beam with third-point loading). Designation: C1609/1609M. West

  12. Photovoltaic Reliability and Engineering (Revised) (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2011-06-01

    Capabilities fact sheet for the National Center for Photovoltaics: Photovoltaic Reliability and Engineering. One-sided sheet that includes Scope, Core Competencies and Capabilities, and Contact/Web information.

  13. Strategic surfaces in sheet metal forming

    DEFF Research Database (Denmark)

    Olsson, David Dam; Andreasen, Jan Lasson; Bay, Niels

    Out-line: Introduction to tribology in sheet metal forming Developed strategic surfaces Tribological testing of strategic surfaces Conclusion......Out-line: Introduction to tribology in sheet metal forming Developed strategic surfaces Tribological testing of strategic surfaces Conclusion...

  14. Investigation of the Failure of Advanced High Strength Steels Heterogeneous Spot Welds

    Directory of Open Access Journals (Sweden)

    Thibaut Huin

    2016-05-01

    Full Text Available Nowadays, environmental regulation encourages carmakers to reduce the global vehicle weight. Steelmakers develop grades with high performance (Advanced High Strength Steels, AHSS and fine steel sheet assemblies are used in car body structures, with an optimized thickness in each part. However, unusual fracture modes are sometimes observed during the mechanical tests of heterogeneous AHSS welds, made of dissimilar steel grades and sheet thicknesses. Weld fractures can occur with a strength lower than expected. This study aims at understanding these fracture mechanisms and focuses on two common steel grades joined by Resistance Spot Welding (RSW: DP600 (a dual phase steel and Usibor®1500 (a martensitic steel. The parameters affecting the failure modes and load bearing capacity are investigated during two common types of tests: the Cross Tension and Tensile Shear tests. The positive effects of heterogeneous welding with respect to the corresponding homogeneous configurations are discussed, as well as the consequences of a so-called Dome failure occurring at the weld nugget boundary.

  15. A Numerical Investigation of CFRP-Steel Interfacial Failure with Material Point Method

    Science.gov (United States)

    Shen, Luming; Faleh, Haydar; Al-Mahaidi, Riadh

    2010-05-01

    The success of retrofitting steel structures by using the Carbon Fibre Reinforced Polymers (CFRP) significantly depends on the performance and integrity of CFRP-steel joint and the effectiveness of the adhesive used. Many of the previous numerical studies focused on the design and structural performance of the CFRP-steel system and neglected the mechanical responses of adhesive layer, which results in the lack of understanding in how the adhesive layer between the CFRP and steel performs during the loading and failure stages. Based on the recent observation on the failure of CFRP-steel bond in the double lap shear tests [1], a numerical approach is proposed in this study to simulate the delamination process of CFRP sheet from steel plate using the Material Point Method (MPM). In the proposed approach, an elastoplasticity model with a linear hardening and softening law is used to model the epoxy layer. The MPM [2], which does not employ fixed mesh-connectivity, is employed as a robust spatial discretization method to accommodate the multi-scale discontinuities involved in the CFRP-steel bond failure process. To demonstrate the potential of the proposed approach, a parametric study is conducted to investigate the effects of bond length and loading rates on the capacity and failure modes of CFRP-steel system. The evolution of the CFRP-steel bond failure and the distribution of stress and strain along bond length direction will be presented. The simulation results not only well match the available experimental data but also provide a better understanding on the physics behind the CFRP sheet delamination process.

  16. Automatic welding of stainless steel tubing

    Science.gov (United States)

    Clautice, W. E.

    1978-01-01

    The use of automatic welding for making girth welds in stainless steel tubing was investigated as well as the reduction in fabrication costs resulting from the elimination of radiographic inspection. Test methodology, materials, and techniques are discussed, and data sheets for individual tests are included. Process variables studied include welding amperes, revolutions per minute, and shielding gas flow. Strip chart recordings, as a definitive method of insuring weld quality, are studied. Test results, determined by both radiographic and visual inspection, are presented and indicate that once optimum welding procedures for specific sizes of tubing are established, and the welding machine operations are certified, then the automatic tube welding process produces good quality welds repeatedly, with a high degree of reliability. Revised specifications for welding tubing using the automatic process and weld visual inspection requirements at the Kennedy Space Center are enumerated.

  17. Numerical Simulation of Duplex Steel Multipass Welding

    Directory of Open Access Journals (Sweden)

    Giętka T.

    2016-12-01

    Full Text Available Analyses based on FEM calculations have significantly changed the possibilities of determining welding strains and stresses at early stages of product design and welding technology development. Such an approach to design enables obtaining significant savings in production preparation and post-weld deformation corrections and is also important for utility properties of welded joints obtained. As a result, it is possible to make changes to a simulated process before introducing them into real production as well as to test various variants of a given solution. Numerical simulations require the combination of problems of thermal, mechanical and metallurgical analysis. The study presented involved the SYSWELD software-based analysis of GMA welded multipass butt joints made of duplex steel sheets. The analysis of the distribution of stresses and displacements were carried out for typical welding procedure as during real welding tests.

  18. 40 CFR 1502.11 - Cover sheet.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Cover sheet. 1502.11 Section 1502.11 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY ENVIRONMENTAL IMPACT STATEMENT § 1502.11 Cover sheet. The cover sheet shall not exceed one page. It shall include: (a) A list of the responsible...

  19. Air Guide for Sheet-Metal Grinder

    Science.gov (United States)

    Heermann, T.

    1984-01-01

    Tool attachment reduces heat distortion of sheet. Air-guide attachment directs air from grinder motor to grinding wheel and metal sheet being ground. Cooling air reduces thermal distortion of workpiece due to localized frictional heating. Particularly useful when grinding sheet metal.

  20. Clean Firetube Boiler Waterside Heat Transfer Surfaces, Energy Tips: STEAM, Steam Tip Sheet #7 (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-04-01

    A steam energy tip sheet for the Advanced Manufacturing Office (AMO). The prevention of scale formation in firetube boilers can result in substantial energy savings. Scale deposits occur when calcium, magnesium, and silica, commonly found in most water supplies, react to form a continuous layer of material on the waterside of the boiler heat exchange tubes. Scale creates a problem because it typically possesses a thermal conductivity, an order of magnitude less than the corresponding value for bare steel. Even thin layers of scale serve as an effective insulator and retard heat transfer. The result is overheating of boiler tube metal, tube failures, and loss of energy efficiency. Fuel consumption may increase by up to 5% in firetube boilers because of scale. The boilers steam production may be reduced if the firing rate cannot be increased to compensate for the decrease in combustion efficiency. Energy losses as a function of scale thickness and composition are given. Any scale in a boiler is undesirable. The best way to deal with scale is not to let it form in the first place. Prevent scale formation by: (1) Pretreating of boiler makeup water (using water softeners, demineralizers, and reverse osmosis to remove scale-forming minerals); (2) Injecting chemicals into the boiler feedwater; and (3) Adopting proper boiler blowdown practices.

  1. Thermomechanical modelling of dissimilar Friction Melt Bonding of AA6061 to Dual-phase steel: Prediction of solidification cracking and residual stresses

    OpenAIRE

    Jimenez Mena, Norberto; Drezet, Jean-Marie; Jacques, Pascal; Simar, Aude; Thermec

    2016-01-01

    Friction Melt Bonding (FMB) is a novel technique that has been successfully applied to weld aluminium to steel in lap-joint configuration. To carry out the weld, a rotating cylindrical tool showing no pin is pressed against the surface of the steel sheet which is placed over the aluminium one. Heat will is generated from the friction and plastic dissipation induced by the tool in the steel plate. This heat does not melt the steel, but locally melts the aluminium in contact underneath owing to...

  2. Application of self compacting concrete for steel-concrete-steel sandwich structure; Hagane concrete full sandwich kozo eno koryudo concrete no tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, M.; Kawamura, R. [Ministry of Transport, Tokyo (Japan); Yuguchi, Y.; Yamamoto, A.

    1998-04-01

    This construction refers to a construction to fabricate a submerged box constituting a submerged tunnel. Since the construction shape thereof is of a steel-concrete-steel sandwich structure (full-sandwich structure), it is indispensable to use self compacting concrete having excellent fillability and very little volumetric change after placement. Therefore, a test construction was performed before the actual construction to select correct mixing of self compacting concrete having good quality and conduct smooth construction. The test provided a very good result presenting no unfilled portions in the actual concrete construction. This paper reports the construction result thereof. This submerged box forms a part of the submerged tunnel linking the urban area of the Kobe city and an artificial island as one of the traffic networks in the port of Kobe. Its construction shape employs the full sandwich structure. The structure is such that sheet steels in place of reinforcing bars and unreinforced concrete filled inside a steel shell enclosed by sheared reinforcing sheet steels are integrated to resist external force. 1 ref., 9 figs., 4 tabs.

  3. Chemical and microstructural diversity of steel grades

    Directory of Open Access Journals (Sweden)

    Zorc, B.

    2002-12-01

    Full Text Available The aim of the paper is to show, using theoretical and practical analyses, chemical and microstructural differences among individual types of steel grades 355 found in the market. The mechanical properties required for these steels are achieved by alloying or thermomechanical treatment. It was found that the individual types of this steel are poorly weldable, particularly those of large thickness.

    El objetivo del artículo es presentar, en base a un análisis teórico y práctico, las diferencias químicas y microestructurales entre los diferentes tipos de aceros calidad 355 que pueden encontrarse en el mercado. Las características mecánicas requeridas en estos aceros se consiguen con aleaciones, o bien a través de tratamientos termo-mecánicos.Se ha llegado a la conclusión de que determinados tipos de acero son más difíciles de soldar, en especial cuando se trata de espesores grandes.

  4. Thermochemical surface engineering of steels

    DEFF Research Database (Denmark)

    Thermochemical Surface Engineering of Steels provides a comprehensive scientific overview of the principles and different techniques involved in thermochemical surface engineering, including thermodynamics, kinetics principles, process technologies and techniques for enhanced performance of steels...

  5. Continuous steel production and apparatus

    Science.gov (United States)

    Peaslee, Kent D [Rolla, MO; Peter, Jorg J [McMinnville, OR; Robertson, David G. C. [Rolla, MO; Thomas, Brian G [Champaign, IL; Zhang, Lifeng [Trondheim, NO

    2009-11-17

    A process for continuous refining of steel via multiple distinct reaction vessels for melting, oxidation, reduction, and refining for delivery of steel continuously to, for example, a tundish of a continuous caster system, and associated apparatus.

  6. Brazing titanium to stainless steel

    Science.gov (United States)

    Batista, R. I.

    1980-01-01

    Titanium and stainless-steel members are usually joined mechanically for lack of any other effective method. New approach using different brazing alloy and plating steel member with nickel resolves problem. Process must be carried out in inert atmosphere.

  7. A tale of Wootz steel

    National Research Council Canada - National Science Library

    Ranganathan, S; Srinivasan, Sharada

    2006-01-01

    The extraordinary romance and thrilling adventure associated with the tale of wootz steel shows how Indian metallurgists were the world leaders in antiquity in the manufacture of this legendary high-grade steel...

  8. Quantum friction between graphene sheets

    Science.gov (United States)

    Farias, M. Belén; Fosco, César D.; Lombardo, Fernando C.; Mazzitelli, Francisco D.

    2017-03-01

    We study the Casimir friction phenomenon in a system consisting of two flat, infinite, and parallel graphene sheets, which are coupled to the vacuum electromagnetic (EM) field. Those couplings are implemented, in the description we use, by means of specific terms in the effective action for the EM field. They incorporate the distinctive properties of graphene, as well as the relative sliding motion of the sheets. Based on this description, we evaluate two observables due to the same physical effect: the probability of vacuum decay and the frictional force. The system exhibits a threshold for frictional effects; namely, they only exist if the speed of the sliding motion is larger than the Fermi velocity of the charge carriers in graphene.

  9. Ice sheet hydrology from observations

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter (Dept. of Physical Geography and Quaternary Geology, Stockholm Univ-, Stockholm (Sweden))

    2010-11-15

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  10. Fatigue damage of steel components

    DEFF Research Database (Denmark)

    Fæster, Søren; Zhang, Xiaodan; Huang, Xiaoxu

    2014-01-01

    Railway rails and the inner ring in roller bearings in wind turbines are both experiencing steel-to-steel contact in small areas with huge loads resulting in extremely high stresses in the base materials......Railway rails and the inner ring in roller bearings in wind turbines are both experiencing steel-to-steel contact in small areas with huge loads resulting in extremely high stresses in the base materials...

  11. Technology to Market Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-02-01

    This fact sheet is an overview of the Technology to Market subprogram at the U.S. Department of Energy SunShot Initiative. The SunShot Initiative’s Technology to Market subprogram builds on SunShot’s record of moving groundbreaking and early-stage technologies and business models through developmental phases to commercialization. Technology to Market targets two known funding gaps: those that occur at the prototype commercialization stage and those at the commercial scale-up stage.

  12. Light Sheet Fluorescence Microscopy (LSFM)

    OpenAIRE

    Adams, Michael W.; Loftus, Andrew F.; Dunn, Sarah E.; Joens, Matthew S.; Fitzpatrick, James A. J.

    2015-01-01

    The development of confocal microscopy techniques introduced the ability to optically section fluorescent samples in the axial dimension, perpendicular to the image plane. These approaches, via the placement of a pinhole in the conjugate image plane, provided superior resolution in the axial (z) dimension resulting in nearly isotropic optical sections. However, increased axial resolution, via pinhole optics, comes at the cost of both speed and excitation efficiency. Light Sheet Fluorescent Mi...

  13. World sheets of spinning particles

    Science.gov (United States)

    Kaparulin, D. S.; Lyakhovich, S. L.

    2017-11-01

    The classical spinning particles are considered such that quantization of classical model leads to an irreducible massive representation of the Poincaré group. The class of gauge equivalent classical particle world lines is shown to form a [(d +1 )/2 ]-dimensional world sheet in d -dimensional Minkowski space, irrespectively to any specifics of the classical model. For massive spinning particles in d =3 , 4, the world sheets are shown to be circular cylinders. The radius of the cylinder is fixed by representation. In higher dimensions, the particle's world sheet turns out to be a toroidal cylinder R ×TD, D =[(d -1 )/2 ]. Proceeding from the fact that the world lines of irreducible classical spinning particles are cylindrical curves, while all the lines are gauge equivalent on the same world sheet, we suggest a method to deduce the classical equations of motion for particles and also to find their gauge symmetries. In d =3 Minkowski space, the spinning particle path is defined by a single fourth-order differential equation having two zero-order gauge symmetries. The equation defines the particle's path in Minkowski space, and it does not involve auxiliary variables. A special case is also considered of cylindric null curves, which are defined by a different system of equations. It is shown that the cylindric null curves also correspond to irreducible massive spinning particles. For the higher-derivative equation of motion of the irreducible massive spinning particle, we deduce the equivalent second-order formulation involving an auxiliary variable. The second-order formulation agrees with a previously known spinning particle model.

  14. Thermally Stable Nanocrystalline Steel

    Science.gov (United States)

    Hulme-Smith, Christopher Neil; Ooi, Shgh Woei; Bhadeshia, Harshad K. D. H.

    2017-10-01

    Two novel nanocrystalline steels were designed to withstand elevated temperatures without catastrophic microstructural changes. In the most successful alloy, a large quantity of nickel was added to stabilize austenite and allow a reduction in the carbon content. A 50 kg cast of the novel alloy was produced and used to verify the formation of nanocrystalline bainite. Synchrotron X-ray diffractometry using in situ heating showed that austenite was able to survive more than 1 hour at 773 K (500 °C) and subsequent cooling to ambient temperature. This is the first reported nanocrystalline steel with high-temperature capability.

  15. Hole expansion test of third generation steels

    Science.gov (United States)

    Agirre, Julen; Mendiguren, Joseba; Galdos, Lander; de Argandoña, Eneko Sáenz

    2017-10-01

    The trend towards the implementation of new materials in the chassis of the automobiles is considerably making more complex the manufacturing of the components that built it up. In this scenario materials with higher strengths and lower formabilities are daily faced by tool makers and component producers what reduces the process windows and makes the forming processes to be in the limits of the materials. One of the concerns that tool makers must face during the definition of the tools is the expansion ratios that the holes in the sheet may reach before producing a breakage due to the stretching of the material (also known as edge cracks). For the characterization of such limits, a standard test, the hole expansion test, can be applied so that the limits of the material are known. At the present study, hole expansion tests of a third generation steel, Fortiform1050 with a thickness of 1.2 millimeters have been carried out and compared them to a mild steel, DX54D with a thickness of 0.6 millimeters. A comparison for each material in terms of technology used to punch the hole, mechanical punching vs laser cutting has also been conducted. In addition, the measurement technique (online measurement vs offline measurement) followed in the Hole Expansion Ratio (HER) identification has also been analyzed. Finally, differences between both materials and techniques are presented.

  16. A-3 steel work completed

    Science.gov (United States)

    2009-01-01

    Stennis Space Center engineers celebrated a key milestone in construction of the A-3 Test Stand on April 9 - completion of structural steel work. Workers with Lafayette (La.) Steel Erector Inc. placed the last structural steel beam atop the stand during a noon ceremony attended by more than 100 workers and guests.

  17. CORRELATION BETWEEN HARDNESS AND TENSILE PROPERTIES IN ULTRA-HIGH STRENGTH DUAL PHASE STEELS – SHORT COMMUNICATION

    Directory of Open Access Journals (Sweden)

    Martin Gaško

    2012-02-01

    Full Text Available The possibility to predict yield strength, strength limit, fatigue live estimation as well as other mechanical properties depending on values of materials hardness is commonly known and it is often used in practice. The main aim of this contribution is to review the possibilities of application of correlation relationships between hardness and ultimate tensile strength of steel sheets in various structural states. The experiments were performed on advanced steels with structure which is composed from ferrite and martensite (dual phase steels.

  18. CORRELATION BETWEEN HARDNESS AND TENSILE PROPERTIES IN ULTRA-HIGH STRENGTH DUAL PHASE STEELS ��� SHORT COMMUNICATION

    Directory of Open Access Journals (Sweden)

    Gejza Rosenberg

    2011-11-01

    Full Text Available The possibility to predict yield strength, strength limit, fatigue live estimation as well as other mechanical properties depending on values of materials hardness is commonly known and it is often used in practice. The main aim of this contribution is to review the possibilities of application of correlation relationships between hardness and ultimate tensile strength of steel sheets in various structural states. The experiments were performed on advanced steels with structure which is composed from ferrite and martensite (dual phase steels.

  19. Friction stir scribe welding technique for dissimilar joining of aluminium and galvanised steel

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tianhao [Center for Friction Stir Processing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, USA; Sidhar, Harpreet [Center for Friction Stir Processing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, USA; Mishra, Rajiv S. [Center for Friction Stir Processing, Department of Materials Science and Engineering, University of North Texas, Denton, TX, USA; Hovanski, Yuri [Pacific Northwest National Laboratory, Energy Materials and Manufacturing, Richland, WA, USA; Upadhyay, Piyush [Pacific Northwest National Laboratory, Energy Materials and Manufacturing, Richland, WA, USA; Carlson, Blair [General Motors Technical Center, Warren, MI, USA

    2017-10-04

    Friction stir scribe technology, a derivative of friction stir welding, was applied for the dissimilar lap welding of an aluminum alloy and galvanized mild steel sheets. During the process, the rotating tool with a cobalt steel scribe first penetrated the top material — aluminum — and then the scribe cut the bottom material — steel. The steel was displaced into the upper material to produce a characteristic hook feature. Lap welds were shear tested, and their fracture paths were studied. Welding parameters affected the welding features including hook height, which turned out to be highly related to fracture position. Therefore, in this paper, the relationships among welding parameters, hook height, joint strength and fracture position are presented. In addition, influence of zinc coating on joint strength was also studied. Keywords: friction stir scribe technology; dissimilar material welding; zinc coating; hook height; joint strength; fracture position

  20. Study on micro fabricated stainless steel surface to anti-biofouling using electrochemical fabrication

    Science.gov (United States)

    Hwang, Byeong Jun; Lee, Sung Ho

    2017-12-01

    Biofilm formed on the surface of the object by the microorganism resulting in fouling organisms. This has led to many problems in daily life, medicine, health and industrial community. In this study, we tried to prevent biofilm formation on the stainless steel (SS304) sheet surface with micro fabricated structure. After then forming the microscale colloid patterns on the surface of stainless steel by using an electrochemical etching forming a pattern by using a FeCl3 etching was further increase the surface roughness. Culturing the Pseudomonas aeruginosa on the stainless steel fabricated with a micro structure on the surface was observed a relationship between the surface roughness and the biological fouling of the micro structure. As a result, the stainless steel surface with a micro structure was confirmed to be the biological fouling occurs less. We expect to be able to solve the problems caused by biological fouling in various fields such as medicine, engineering, using this research.

  1. Formation of Outburst Structure in Hot Dip Galvannealed Coatings on IF Steels

    Directory of Open Access Journals (Sweden)

    Kollárová, M.

    2007-01-01

    Full Text Available Outburst structure in two industrially produced hot dip galvanized interstitial free steel sheets for automotive industry after additional annealing has been examined. Ti IF steel was found to form weak outburst structure in the early stage of annealing, followed by frontal growth of Fe-Zn phases during further heating. The high reactivity of this steel was confirmed by rapid G-phase formation. Under the same conditions, Ti-Nb-P IF steel exhibited frontal growth of Fe-Zn compounds without G-phase formation due to relatively high phosphorous content, which is known as inhibitor of Fe-Zn reaction, but simultaneously significant occurrence of undesired outburst structures was recorded. It was assumed that the phosphorous content was insufficient and/or ferrite grain was very fine.

  2. Numerical and experimental study on multi-pass laser bending of AH36 steel strips

    Science.gov (United States)

    Fetene, Besufekad N.; Kumar, Vikash; Dixit, Uday S.; Echempati, Raghu

    2018-02-01

    Laser bending is a process of bending of plates, small sized sheets, strips and tubes, in which a moving or stationary laser beam heats the workpiece to achieve the desired curvature due to thermal stresses. Researchers studied the effects of different process parameters related to the laser source, material and workpiece geometry on laser bending of metal sheets. The studies are focused on large sized sheets. The workpiece geometry parameters like sheet thickness, length and width also affect the bend angle considerably. In this work, the effects of width and thickness on multi-pass laser bending of AH36 steel strips were studied experimentally and numerically. Finite element model using ABAQUS® was developed to investigate the size effect on the prediction of the bend angle. Microhardness and flexure tests showed an increase in the flexural strength as well as microhardness in the scanned zone. The microstructures of the bent strips also supported the physical observations.

  3. Feasibility analysis of recycling radioactive scrap steel

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, F. [Manufacturing Sciences Corp., Woodland, WA (United States); Balhiser, B. [MSE, Inc., Butte, MT (United States); Cignetti, N. [Cignetti Associates, North Canton, OH (United States)] [and others

    1995-09-01

    The purpose of this study is to: (1) establish a conceptual design that integrates commercial steel mill technology with radioactive scrap metal (RSM) processing to produce carbon and stainless steel sheet and plate at a grade suitable for fabricating into radioactive waste containers; (2) determine the economic feasibility of building a micro-mill in the Western US to process 30,000 tons of RSM per year from both DOE and the nuclear utilities; and (3) provide recommendations for implementation. For purposes of defining the project, it is divided into phases: economic feasibility and conceptual design; preliminary design; detail design; construction; and operation. This study comprises the bulk of Phase 1. It is divided into four sections. Section 1 provides the reader with a complete overview extracting pertinent data, recommendations and conclusions from the remainder of the report. Section 2 defines the variables that impact the design requirements. These data form the baseline to create a preliminary conceptual design that is technically sound, economically viable, and capitalizes on economies of scale. Priorities governing the design activities are: (1) minimizing worker exposure to radionuclide hazards, (2) maximizing worker safety, (3) minimizing environmental contamination, (4) minimizing secondary wastes, and (5) establishing engineering controls to insure that the plant will be granted a license in the state selected for operation. Section 3 provides details of the preliminary conceptual design that was selected. The cost of project construction is estimated and the personnel needed to support the steel-making operation and radiological and environmental control are identified. Section 4 identifies the operational costs and supports the economic feasibility analysis. A detailed discussion of the resulting conclusions and recommendations is included in this section.

  4. Microbial-Influenced Corrosion of Corten Steel Compared with Carbon Steel and Stainless Steel in Oily Wastewater by Pseudomonas aeruginosa

    Science.gov (United States)

    Mansouri, Hamidreza; Alavi, Seyed Abolhasan; Fotovat, Meysam

    2015-07-01

    The microbial corrosion behavior of three important steels (carbon steel, stainless steel, and Corten steel) was investigated in semi petroleum medium. This work was done in modified nutrient broth (2 g nutrient broth in 1 L oily wastewater) in the presence of Pseudomonas aeruginosa and mixed culture (as a biotic media) and an abiotic medium for 2 weeks. The behavior of corrosion was analyzed by spectrophotometric and electrochemical methods and at the end was confirmed by scanning electron microscopy. The results show that the degree of corrosion of Corten steel in mixed culture, unlike carbon steel and stainless steel, is less than P. aeruginosa inoculated medium because some bacteria affect Corten steel less than other steels. According to the experiments, carbon steel had less resistance than Corten steel and stainless steel. Furthermore, biofilm inhibits separated particles of those steels to spread to the medium; in other words, particles get trapped between biofilm and steel.

  5. Behavior of Steel-Sheathed Shear Walls Subjected to Seismic and Fire Loads.

    Science.gov (United States)

    Hoehler, Matthew S; Smith, Christopher M; Hutchinson, Tara C; Wang, Xiang; Meacham, Brian J; Kamath, Praveen

    2017-07-01

    A series of tests was conducted on six 2.7 m × 3.7 m shear wall specimens consisting of cold-formed steel framing sheathed on one side with sheet steel adhered to gypsum board and on the opposite side with plain gypsum board. The specimens were subjected to various sequences of simulated seismic shear deformation and fire exposure to study the influence of multi-hazard interactions on the lateral load resistance of the walls. The test program was designed to complement a parallel effort at the University of California, San Diego to investigate a six-story building subjected to earthquakes and fires. The test results reported here indicate that the fire exposure caused a shift in the failure mode of the walls from local buckling of the sheet steel in cases without fire exposure, to global buckling of the sheet steel with an accompanying 35 % reduction in lateral load capacity after the wall had been exposed to fire. This behavior appears to be predictable, which is encouraging from the standpoint of residual lateral load capacity under these severe multi-hazard actions.

  6. Study of Microstructure and Mechanical Properties Effects on Workpiece Quality in Sheet Metal Extrusion Process.

    Science.gov (United States)

    Suriyapha, Chatkaew; Bubphachot, Bopit; Rittidech, Sampan

    2015-01-01

    Sheet metal extrusion is a metal forming process in which the movement of a punch penetrates a sheet metal surface and it flows through a die orifice; the extruded parts can be deflected to have an extrusion cavity and protrusion on the opposite side. Therefore, this process results in a narrow region of highly localized plastic deformation due to the formation and microstructure effect on the work piece. This research investigated the characteristics of the material-flow behavior during the formation and its effect on the microstructure of the extruded sheet metal using the finite element method (FEM). The actual parts and FEM simulation model were developed using a blank material made from AISI-1045 steel with a thickness of 5 mm; the material's behavior was determined subject to the punch penetration depths of 20%, 40%, 60%, and 80% of the sheet thickness. The results indicated the formation and microstructure effects on the sheet metal extrusion parts and defects. Namely, when increasing penetration, narrowing the die orifice the material flows through, the material was formed by extruding, and defects were visibility, and the microstructure of the material's grains' size was flat and very fine. Extrusion defects were not found in the control material flow. The region of highly localized plastic deformation affected the material gain and mechanical properties. The FEM simulation results agreed with the experimental results. Moreover, FEM could be investigated as a tool to decrease the cost and time in trial and error procedures.

  7. Guns, Germs and Steel

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 1. Guns, Germs and Steel - A Short History of Everybody for the Last 13,000 years. Suri Venkatachalam. Book Review Volume 6 Issue 1 January 2001 pp 84-88. Fulltext. Click here to view fulltext PDF. Permanent link:

  8. Japan steel mill perspective

    Energy Technology Data Exchange (ETDEWEB)

    Murase, K. [Kobe Steel Ltd., Tokyo (Japan)

    2004-07-01

    The international and Japan's steel industry, the coking coal market, and Japan's expectations from Canada's coal industry are discussed. Japan's steel mills are operating at full capacity. Crude steel production for the first half of 2004 was 55.8 million tons. The steel mills are profitable, but costs are high, and there are difficulties with procuring raw materials. Japan is trying to enhance the quality of coke, in order to achieve higher productivity in the production of pig iron. Economic growth is rising disproportionately in the BRICs (Brazil, Russia, India, and China), with a large increase in coking coal demand from China. On the supply side, there are several projects underway in Australia and Canada to increase production. These include new developments by Elk Valley Coal Corporation, Grande Cache Coal, Western Canadian Coal, and Northern Energy and Mining in Canada. The Elga Mine in the far eastern part of Russia is under development. But the market is expected to remain tight for some time. Japan envisions Canadian coal producers will provide a stable coal supply, expansion of production and infrastructure capabilities, and stabilization of price. 16 slides/overheads are included.

  9. Braze alloy spreading on steel

    Science.gov (United States)

    Siewert, T. A.; Heine, R. W.; Lagally, M. G.

    1978-01-01

    Scanning electron microscopy (SEM) and Auger electron microscopy (AEM) were employed to observe elemental surface decomposition resulting from the brazing of a copper-treated steel. Two types of steel were used for the study, stainless steel (treated with a eutectic silver-copper alloy), and low-carbon steel (treated with pure copper). Attention is given to oxygen partial pressure during the processes; a low enough pressure (8 x 10 to the -5th torr) was found to totally inhibit the spreading of the filler material at a fixed heating cycle. With both types of steel, copper treatment enhanced even spreading at a decreased temperature.

  10. Fiscal 1997 report on the results on the international standardization R and D. Development of chemical methods to analyze/evaluate metallic coatings of surface treated steel coating sheets; 1997 nendo seika hokokusho kokusai hyojun soseigata kenkyu kaihatsu. Hyomen shori koban mekkiso no kagaku bunseki hyoka hoho no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The paper studied the international standardization of the chemical analysis method and glow discharge optical emission spectrometry. Chemical composition and coating thickness (g/m{sup 2}) of 14 kinds of specimens including alloy coatings and organic coating with zinc and aluminum as base were analyzed by the above-mentioned methods to examine the relation between the both. As the chemical analysis method, used was inductively coupled plasma atomic emission spectrometry. To study the relation between the methods, it was found to be necessary to recognize morphology at the boundary between the coating and base steel using, for example, scanning electron microscope (SEM) and electro-probe micro-analysis (EPMA). To measure traceability of the analysis method, with the chemical analysis method as a judgement method, it is necessary to make reference materials by coating materials, to use the calibration graph confirmed by the materials and to adopt the glow discharge optical emission spectrometry. On the basis of such way of thinking, drafts were worked out for the international standardization of the chemical analysis method and glow discharge optical emission spectrometry. 7 refs., 117 figs., 33 tabs.

  11. Formability Evaluation of Low-Carbon Steel Strip

    Directory of Open Access Journals (Sweden)

    Radek ČADA

    2011-06-01

    Full Text Available Contribution concerns formability evaluation of low-carbon steel strip St 4, which is used for production of intricate deep stampings. The properties of sheet-metal which have the principal influence upon the success of deep drawing or strech-forming are described, i. e. directional and mean values of mechanical properties, the values of coefficients of planar anisotropy of mechanical properties, directional and mean values of coefficients of normal plastic anisotropy ratio, directional and mean values of strain-hardening exponents. From values, evaluated by tensile tests, the forming limit diagram, which comes out from criterion of plastic deformation stability loss at the tensile strength, can be constructed. These diagrams are advantageous for comparison of sheet-metal plastic properties at various stress states or in range of stresses according to the working up technology.

  12. Effect of Dwell Time on Joint Interface Microstructure and Strength of Dissimilar Friction Stir Spot-Welded Al-5083 and St-12 Alloy Sheets

    Science.gov (United States)

    Fereiduni, Eskandar; Movahedi, Mojtaba; Kokabi, Amir Hossein; Najafi, Hossein

    2017-04-01

    Joining of Al-5083 alloy sheet to St-12 steel sheet was performed using a new friction stir spot welding (FSSW) technique in which the tool pin tip did not enter lower steel sheet. Effect of dwell time on the microstructure and mechanical properties of the joints was studied by various methods including microhardness measurements, shear test, stereo and light microscopy as well as scanning and transmission electron microscopy (SEM and TEM). Results indicated that compared to the conventional FSSW process, stronger joints can be achieved by this FSSW technique. Cross-sectional observation of the failed specimens indicated the occurrence of final fracture from the circumference of the tool pin where the Al sheet thickness was decreased as a result of the tool pin penetration. However, microhardness measurements introduced these fracture locations as the hardest regions of the Al part of welds. In addition to the Al3Fe and Al5Fe2 intermetallic compounds reported in the literature to form at the interface of dissimilar Al/steel joints, a third layer of AlFe intermetallic compound was also identified adjacent to the steel side of welds. Enhancement of the dwell time from 5 to 15 seconds increased the intermetallic layer thickness from 1.7 to 3 µm and resulted in the formation of harder stirred zone. This consequently increased the strength of the weld.

  13. Un cuerpo propio* Performatividad(es) en la(s) identidad(es) infantil(es)

    OpenAIRE

    Bonilla Rodríguez, Hebe

    2015-01-01

    “Un(os) cuerpo(s) propio(s)*. Performatividades en la identidades infantiles” es una reflexión sobre la infancia. Esta etnografía pretende adoptar una mirada heterodoxa de las personas en edades comprendidas entre los cuatro y los seis años. Para ello, se cuestiona las frecuentes estandarizaciones homogeneizadoras de dichas personas. Dicho cuestionamiento tiene la finalidad de adoptar otra forma de mirar a esas personas; una mirada que nos permita mostrarlas como un grupo vivo ...

  14. Natural(es) remisión de V. ciencias natural(es).

    OpenAIRE

    2011-01-01

    [ES] Definición del término Natural(es) remisión de V. ciencias natural(es). en el diccionario Dicter. [EN] Definition of the word Natural(es) remisión de V. ciencias natural(es). in the dictionary Dicter.

  15. High specialty stainless steels and nickel alloys for FGD dampers

    Energy Technology Data Exchange (ETDEWEB)

    Herda, W.R.; Rockel, M.B.; Grossmann, G.K. [Krupp VDM GmbH, Werdohl (Germany); Starke, K. [Mannesmann-Seiffert GmbH, Beckum (Germany)

    1997-08-01

    Because of process design and construction, FGD installations normally have bypass ducts, which necessitates use of dampers. Due to corrosion from acid dew resulting from interaction of hot acidic flue gases and colder outside environments, carbon steel cannot be used as construction material under these specific conditions. In the past, commercial stainless steels have suffered by pitting and crevice corrosion and occasionally failed by stress corrosion cracking. Only high alloy specialty super-austenitic stainless steels with 6.5% Mo should be used and considered for this application. Experience in Germany and Europe has shown that with regard to safety and life cycle cost analysis as well as providing a long time warranty, a new specialty stainless steel, alloy 31--UNS N08031--(31 Ni, 27 Cr, 6.5 Mo, 0.2 N) has proven to be the best and most economical choice. Hundreds of tons in forms of sheet, rod and bar, as well as strip (for damper seals) have been used and installed in many FGD installations throughout Europe. Under extremely corrosive conditions, the new advanced Ni-Cr-Mo alloy 59--UNS N06059--(59 Ni, 23 Cr, 16 Mo) should be used. This paper describes qualification and workability of these alloys as pertains to damper applications. Some case histories are also provided.

  16. CORROSION AND CHEMICAL WASTE IN SAWBLADES STEEL USED IN WOOD

    Directory of Open Access Journals (Sweden)

    Paulo Fernando Trugilho

    2002-01-01

    Full Text Available The objective this work was to evaluate the chemical waste provoked by the wood on the sheets of steel used in the making of the mountains and cut tools. It was certain the correlationbetween the chemical waste and the extractive soluble in cold water, hot water and in the sequencetoluene and ethanol content. Two types of steel and twenty-seven species different from wood wereused. The corrosive agent, constituted of 50 g of fresh sawdust (moist mixed to 50 ml of distilledwater, it was prepared and placed inside of the plastic box, hermetically closed, on the samples ofsteel, which were totally immersed. The box was placed in a water bath pre-heated to 75°C, that themedium temperature of reaction is considered, that affects the sheet of the sawblade in operation. Thisgroup was operated to 80 rotations per minute (rpm. The time of reaction was of four hours. Afterthat time the corrosive agent was discarded and the samples were washed, dried and weighed. At theend, each sample was processed by a total period of forty hours. The chemical waste was evaluated by the weight difference suffered from beginning at the end of the experiment. For theresults it was observed that the Eucalyptus tradryphloia and the Eucalyptus phaeotricha the speciesthat provoked were, respectively, the largest and smaller chemical waste for the two types of steelappraised. Great variation exists in the chemical waste due to the effect of the species. The corrosionand chemical waste are especially related with the quality of the material solved in ethanol. The 1070steel were more attached than the 6170 steel.

  17. Religions mondialisées.

    Directory of Open Access Journals (Sweden)

    Sébastien Fath

    2002-05-01

    Full Text Available « Dès le début de l’histoire, les croyances religieuses manifestent une tendance à ne pas se renfermer dans une société politique étroitement délimitée : il y a en elles comme une aptitude naturelle à passer par-dessus les frontières, à se diffuser, à s’internationaliser ». Ces réflexions d’Émile Durkheim, extraites des Formes élémentaires de la vie religieuse , sont placées en exergue de l’ouvrage d’Ariel Colonomos consacré aux « Églises en réseau ». ...

  18. AA6082 to DX56-Steel Laser Brazing: Process Parameter-Intermetallic Formation Correlation

    Science.gov (United States)

    Narsimhachary, D.; Pal, S.; Shariff, S. M.; Padmanabham, G.; Basu, A.

    2017-09-01

    In the present study, laser-brazed AA6082 to DX56-galvanized steel joints were investigated to understand the influence of process parameters on joint strength in terms of intermetallic layer formation. 1.5-mm-thick sheet of aluminum alloy (AA6082-T6) and galvanized steel (DX56) sheet of 0.7 mm thickness were laser-brazed with 1.5-mm-diameter Al-12% Si solid filler wire. During laser brazing, laser power (4.6 kW) and wire feed rate (3.4 m/min) were kept constant with a varying laser scan speed of 3.5, 3, 2.5, 2, 1.5, and 1 m/min. Microstructure of brazed joint reveals epitaxial growth at the aluminum side and intermetallic layer formation at steel interface. Intermetallic layer formation was confirmed by EDS analysis and XRD study. Hardness profile showed hardness drop in filler region, and failure during tensile testing was initiated through the filler region near the steel interface. As per both experimental study and numerical analysis, it was observed that intermetallic layer thickness decreases with increasing brazing speed. Zn vaporization from galvanized steel interface also affected the joint strength. It was found that high laser scan speed or faster cooling rate can be chosen for suppressing intermetallic layer formation or at least decreasing the layer thickness which results in improved mechanical properties.

  19. FY 1998 result report. Report on the results of the examinational research on the trend of technology development in the iron/steel industry; 1998 nendo seika hokokusho. Tekko sangyo no gijutsu kaihatsu doko nado ni kansuru chosa kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    The trend of the technology development in the Japanese iron/steel industry was compared with those in foreign countries and surveyed to increase the international competitive strength. From the viewpoints of technology, industry and goods, the iron/steel field was characterized based on the statistic data, and especially automobile use steel materials were selected such as cold rolling high tension steel sheet, surface treated steel sheet, and bearing sheet. The analysis of factors of competitive superiority was conducted, and the following were presented: measures for process continuation, and measures taken from the age of equipment and cost indexes. The paper also surveyed the trend of pig iron making/steel making technology in Asia. The present international technical competitiveness in the iron/steel industry in Japan, especially of automobile use steel sheet, is very high. This is because of the well-functioned demand-oriented development, and also as a result of the mutually influentially conducted equipment development such as process continuation and development of new goods, supposing the iron/steel continuous process and reduction in impurities. However, fears are the stagnation in the recent technical development strength and the saturation of new equipment. Moreover, the further heightening is needed of the international cost competitive strength of general-purpose products. (NEDO)

  20. AI applications in sheet metal forming

    CERN Document Server

    Hussein, Hussein

    2017-01-01

    This book comprises chapters on research work done around the globe in the area of artificial intelligence (AI) applications in sheet metal forming. The first chapter offers an introduction to various AI techniques and sheet metal forming, while subsequent chapters describe traditional procedures/methods used in various sheet metal forming processes, and focus on the automation of those processes by means of AI techniques, such as KBS, ANN, GA, CBR, etc. Feature recognition and the manufacturability assessment of sheet metal parts, process planning, strip-layout design, selecting the type and size of die components, die modeling, and predicting die life are some of the most important aspects of sheet metal work. Traditionally, these activities are highly experience-based, tedious and time consuming. In response, researchers in several countries have applied various AI techniques to automate these activities, which are covered in this book. This book will be useful for engineers working in sheet metal industri...

  1. Finite element analysis of non-isothermal warm deep drawing of dual phase steel

    Directory of Open Access Journals (Sweden)

    Pepelnjak T.

    2016-01-01

    Full Text Available Improving the formability of the material is an important issue in the deep drawing process. Heating the material above its recrystallization temperature drastically increases formability but in the case of dual phase (DP steels it results in the loss of their mechanical properties. To improve the drawing ratio, only the heating of the flange region in the warm temperature range up to 300°C was studied on DP600 sheet steel by numerical simulation. Thermo-elastic-plastic FEM analysis of deep drawing at several drawing ratios was performed and compared with experimental results.

  2. Experimental Studies of New Joint System for Thin-Walled Steel Profiles

    OpenAIRE

    Octavian Roşca; I. P. Ciongradi; M. Budescu

    2006-01-01

    The results and conclusions regarding the experimental test of the joint assembly of thin walled steel profile with and without strengthening elements (stiffeners) are presented. The entire test series have been performed using the 5 mm thick KB600 thin-walled profiles and 3.5 mm thick KB450. In the paper will be presented the analysis of the joints connecting the KB600-5.5 steel profiles. The KONTIBEAM system is primarily made of two galvanized sheet profiles so denominated as KB, which are ...

  3. Formability and fracture studies of austenitic stainless steel 316 at different temperatures

    OpenAIRE

    Hussaini, Syed Mujahed; Singh, Swadesh Kumar; Gupta, Amit Kumar

    2014-01-01

    Deep drawing is one of the most important sheet metal forming processes in automotive, aerospace and nuclear industries. In this process, the sheet metal blank is formed into a cup shape by an application of punch into the die. The present work is aimed at studying the formability and the nature of fracture for one of the important materials in industrial applications, austenitic stainless steel 316 at different temperatures. Circular blanks were deep drawn at room temperature, 150 and 300 °C...

  4. Influence of Corrugation Depth on Lateral Stability of Cold-Formed Steel Beams of Corrugated Webs

    OpenAIRE

    Ungureanu Viorel; Dubina Dan

    2016-01-01

    The beams of thin corrugated web afford a significant weight reduction compared with hot-rolled or welded ones. In the initial solutions, the flanges are made of flat plates, welded to the sinusoidal web sheet, requiring a specific welding technology. A new solution is proposed by the authors, in which the beam is composed by a web of trapezoidal cold-formed steel sheet and flanges of back-to-back lipped channel sections. For connecting flanges to the web self-drilling screws are used. The pa...

  5. History of ultrahigh carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Wadsworth, J.; Sherby, O.D.

    1997-06-20

    The history and development of ultrahigh carbon steels (i.e., steels containing between 1 and 2.l percent C and now known as UHCS) are described. The early use of steel compositions containing carbon contents above the eutectoid level is found in ancient weapons from around the world. For example, both Damascus and Japanese sword steels are hypereutectoid steels. Their manufacture and processing is of interest in understanding the role of carbon content in the development of modern steels. Although sporadic examples of UHCS compositions are found in steels examined in the early part of this century, it was not until the mid-1970s that the modern study began. This study had its origin in the development of superplastic behavior in steels and the recognition that increasing the carbon content was of importance in developing that property. The compositions that were optimal for superplasticity involved the development of steels that contained higher carbon contents than conventional modern steels. It was discovered, however, that the room temperature properties of these compositions were of interest in their own right. Following this discovery, a period of intense work began on understanding their manufacture, processing, and properties for both superplastic forming and room temperature applications. The development of superplastic cast irons and iron carbides, as well as those of laminated composites containing UHCS, was an important part of this history.

  6. Gadolinium sheet converter for neutron radiography

    Energy Technology Data Exchange (ETDEWEB)

    Lima, C.T.S. [Laboratorio de Neutrongrafia em Tempo Real (LNRTR/PEN/COPPE), Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21941-972 Rio de Janeiro, RJ (Brazil); Crispim, V.R. [Laboratorio de Neutrongrafia em Tempo Real (LNRTR/PEN/COPPE), Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21941-972 Rio de Janeiro, RJ (Brazil); PEN/COPPE-DNC/Escola Politecnica CT, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21941-972 Rio de Janeiro, RJ (Brazil)], E-mail: verginia@con.ufrj.br; Santos, W.M.S. [Laboratorio de Colisao Atomica e Molecular (LACAM/IF), Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68528, 21941-972 Rio de Janeiro, RJ (Brazil)

    2007-12-15

    This work describes a methodology developed for the confection of gadolinium sheet converter for neutron radiography using the gadolinium chloride (GdCl{sub 3}) as material converter. Though manufactured at a relatively low cost, they are as good as the sheet converter on the market. Here, we present neutron radiography of the penetrameter, the edge spread function, the modulation transfer function and characteristic curves for each set sheet-AA400 Kodak film.

  7. Shape Optimization of Swimming Sheets

    Energy Technology Data Exchange (ETDEWEB)

    Wilkening, J.; Hosoi, A.E.

    2005-03-01

    The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical value. We explore the validity of the lubrication approximation near this singular limit by monitoring higher order corrections to the zeroth order theory and by comparing the results with finite element solutions of the full Stokes equations.

  8. Light Sheet Fluorescence Microscopy (LSFM).

    Science.gov (United States)

    Adams, Michael W; Loftus, Andrew F; Dunn, Sarah E; Joens, Matthew S; Fitzpatrick, James A J

    2015-01-05

    The development of confocal microscopy techniques introduced the ability to optically section fluorescent samples in the axial dimension, perpendicular to the image plane. These approaches, via the placement of a pinhole in the conjugate image plane, provided superior resolution in the axial (z) dimension resulting in nearly isotropic optical sections. However, increased axial resolution, via pinhole optics, comes at the cost of both speed and excitation efficiency. Light sheet fluorescent microscopy (LSFM), a century-old idea made possible with modern developments in both excitation and detection optics, provides sub-cellular resolution and optical sectioning capabilities without compromising speed or excitation efficiency. Over the past decade, several variations of LSFM have been implemented each with its own benefits and deficiencies. Here we discuss LSFM fundamentals and outline the basic principles of several major light-sheet-based imaging modalities (SPIM, inverted SPIM, multi-view SPIM, Bessel beam SPIM, and stimulated emission depletion SPIM) while considering their biological relevance in terms of intrusiveness, temporal resolution, and sample requirements. Copyright © 2015 John Wiley & Sons, Inc.

  9. Modelling Steel Behaviour

    OpenAIRE

    Anderberg, Yngve

    1986-01-01

    When modelling material mechanical behaviour, an analytical description is required of the relationship between stresses and strains. A computer oriented mechanical behaviour model for steel is described. The model is based on the fact that the deformation process at transient high temperature conditions can be desribed by three strain components which are separately found in different steady state tests. It is shown that a behaviour model based on steady state data satisfactorily predicts be...

  10. Wootz Damascus steel blades

    Energy Technology Data Exchange (ETDEWEB)

    Verhoeven, J.D.; Gibson, E.D. [Ames Lab., IA (United States); Pendray, A.H. [ABS Master Bladesmith, Williston, FL (United States)

    1996-07-01

    Wootz Damascus steel blades contain surface patterns produced by bands of cementite particles which are generated in situ as the blades are forged from small ingots. A process for making these blades has recently been developed which involves making ingots in a gas-fired furnace followed by forging to blade shapes. This study presents a series of additional experiments which provide strong evidence that the mechanism responsible for the formation of the aligned cementite bands is similar to the mechanism that produces banded hypoeutectoid steels. That mechanism attributes the selective formation of ferrite bands to microsegregated alloying elements. The results of this study show that the cementite bands will form in ultraclean hypereutectoid steels (P and S levels <0.003 wt. %) by the addition of small amounts of carbide-forming elements V, Cr, and Ti at a combined level of <0.02 wt. %. The results present strong evidence that the cementite bands are formed by a selective coarsening of cementite particles during the thermal cycling of the forging process. The particle coarsening is induced to occur preferentially in the interdendritic regions of the alloys by the very small additions of the carbide-forming elements.

  11. Climate modification by future ice sheet changes and consequences for ice sheet mass balance

    OpenAIRE

    Vizcaino, M.; Mikolajewicz, U.; J. Jungclaus; G. Schurgers

    2010-01-01

    The future evolution of global ice sheets under anthropogenic greenhouse forcing and its impact on the climate system, including the regional climate of the ice sheets, are investigated with a comprehensive earth system model consisting of a coupled Atmosphere-Ocean General Circulation Model, a dynamic vegetation model and an ice sheet model. The simulated control climate is realistic enough to permit a direct coupling of the atmosphere and ice sheet components, avoiding the use of anomaly co...

  12. Steel desulphurization with synthetic slag

    Directory of Open Access Journals (Sweden)

    Heput, T.

    2007-02-01

    Full Text Available Generally speaking, sulphur is considered a harmful element for steel quality, reason why all the technological steps are being taken in order to eliminate it from the metal bath. This paper deals with the influence of the chemical composition, on the slag quantity and of the bath stirring condition upon the desulphurization process in the casting ladle by treatment with synthetic slag. The experiments were made at an open-hearth plant with the steel tapping in two ladles (the desulphurization was made with synthetic slag at one ladle while the other one was considered standard and at the electric steel plant and for the synthetic slag formation a mix was used, made, according to several receipts, of: lime (50-75%, fluorine (0-17%, bauxite (0-32% and aluminous slag (8-22%. The data were processed in the calculation programs EXCEL and MATLAB, which resulted in a series of correlations between the desulphurization degree and the chemical composition of the slag, respectively the slag quantity both for the charges bubbled with Argon and the unbubbled ones.

    En general, el azufre es considerado un elemento nocivo para la calidad del acero y, por eso, en la práctica, se toman todas las medidas de orden tecnológico para su eliminación del baño metálico. En este trabajo se analiza la influencia de la composición química, de la cantidad de escoria y del estado de agitación del baño sobre el proceso de desulfuración en la cuchara para fundir por tratamiento con escoria sintética. Los experimentos se han realizado en una acería evacuando el acero en dos ollas (en una cuchara se efectuó la desulfuración con escoria sintética y a la otra se consideró como patrón y en un acería eléctrica y para la formación de la escoria sintética se utilizó una mezcla producida según muchas recetas, formada por: cal (50-75%, fluorina (0-17%, bauxita (0-32% y escoria aluminosa (8-22%. Los datos han sido procesados en los programas de c

  13. Fracture Mechanisms in Steel Castings

    Directory of Open Access Journals (Sweden)

    Stradomski Z.

    2013-09-01

    Full Text Available The investigations were inspired with the problem of cracking of steel castings during the production process. A single mechanism of decohesion - the intergranular one - occurs in the case of hot cracking, while a variety of structural factors is decisive for hot cracking initiation, depending on chemical composition of the cast steel. The low-carbon and low-alloyed steel castings crack due to the presence of the type II sulphides, the cause of cracking of the high-carbon tool cast steels is the net of secondary cementite and/or ledeburite precipitated along the boundaries of solidified grains. Also the brittle phosphor and carbide eutectics precipitated in the final stage solidification are responsible for cracking of castings made of Hadfield steel. The examination of mechanical properties at 1050°C revealed low or very low strength of high-carbon cast steels.

  14. Triggering of explosive reconnection in a thick current sheet via current sheet compression: Less current sheet thinning, more temperature anisotropy

    Science.gov (United States)

    Shimizu, K.; Shinohara, I.; Fujimoto, M.

    2016-12-01

    Two-dimensional kinetic simulations of compression of thick current sheets are performed to see how it can lead to triggering of explosive magnetic reconnection. The current sheet under study is simply in a Harris-like anti-paralell and symmetric geometry. A one-dimensional pre-study shows that the compression is more effective to make the plasma anisotropy than to thin the current sheet width. When the lobe magnetic field is amplified by a factor of 2, the plasma temperature anisotropy inside the current sheet reaches 2 but the current sheet thickness is reduced only by 1/sqrt(2). If a current sheet thickness needs to be comparable to the ion inertial scale for reconnection triggering take place, as is widely and frequently mentioned in the research community, the initial thickness cannot be more than a few ion scale for reconnection to set-in. On the other hand, the temperature anisotropy of 2 can be significant for the triggering problem. Two-dimensional simulations show explosive magnetic reconnection to take place even when the initial current sheet thickness more than an order of magnitude thicker than the ion scale, indicating the resilient triggering drive supplied by the temperature anisotropy. We also discuss how the reconnection triggering capability of the temperature anisotropy boosted tearing mode for thick current sheets compares with the instabilities in the plane orthogonal to the reconnecting field.

  15. Aircraft Sheet Metal Practices, Blueprint Reading, Sheet Metal Forming and Heat Treating; Sheet Metal Work 2: 9855.04.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    This course is designed to familiarize vocational students with construction in sheet metal layout. The document outlines goals, specific block objectives, layout practices, blueprint reading, sheet metal forming (by hand and by machine), and heat treatment of metals, and includes posttest samples. Layout techniques and air foil developing are…

  16. Pensées intimes

    CERN Document Server

    Einstein, Albert

    2000-01-01

    A quelqu'un qui lui demandant pourquoi les hommes pouvaient découvrir les atomes, mais pas les moyens de les contrôler, Einstein répondit : " C'est simple, mon ami : parce que la politique est plus difficile que la physique ". Albert Einstein était un écrivain prolifique dont l'œuvre abonde en aphorismes. Les 550 citations de ce recueil, tirées des quelque 40 000 documents des Archives Einstein, nous font découvrir le Einstein de la légende, l'ami des écoliers et des étudiants fauchés, le philosophe de la vie quotidienne, doux et ironique, mais aussi la face plus sombre, parfois désespérée, de ce grand génie de l'ère moderne. Qu'il s'exprime sur des sujets aussi variés que l'Amérique et les Américains, l'Allemagne et les Allemands, les Juifs et le sionisme, la guerre et le pacifisme, la politique, la religion et la science, ou sur des thèmes plus personnels, tels que l'amour et le mariage, la jeunesse et la vieillesse l'avortement ou l'homosexualité, ses propos restent toujours mordants,...

  17. Synthesis of thermit noncorrodible steels

    OpenAIRE

    Жигуц, Юрій Юрійович

    2013-01-01

    The present paper the basic solutions to the problem of obtaining cavitation-resistant steels examined the use of thermite steels, the benefits of combining thermite steels with metallotermic methods of getting is showed. The advantages of metallotermic synthesis methods include: autonomy of processes, independence of energy sources, simplicity of equipment, high-performance process and easy transition from experimental research to industrial production. The need to developed the technology o...

  18. Compression test of cold-formedsteel perforated profile with steel sheathing

    Directory of Open Access Journals (Sweden)

    Shamanin Aleksandr Yur’evich

    2015-05-01

    Full Text Available The subject of this paper is the stability and strength of cold-formed and perforated steel sigma-section columns with steel sheathing of different thickness. Ceilings with and without steel sheathing of different thickness are tested to failure in compression on a laboratory machine, which was based on a manual hydraulic jack. Series of 4 experiments with full-scale walls (2.5 m height were carried out. Also, for examination of the role of boundary conditions, the sheet in a ceiling is either left free or connected to base with screws.In civil engineering there are many experiments and methodologies for calculating the strength and buckling of ceiling with the sheathing of various materials, such as oriented strand board and gypsum board. However, for producing superstructures of ships the materials with high plastic properties and strength characteristics are required. For example steel possesses such properties. It was the main reason for conducting a series of experiments and studying the behavior of cold-formed steel columns with steel sheathing. During the experiments the deformation of the cross-section of three equally spaced cross sections was determined, as well as the axial deformation of the central column in the ceiling with steel sheathing.The test results showed the influence of the thickness of sheathing and boundary condition of a sheet on the strength and buckling of ceiling. According to the results of the tests it is necessary to evaluate the impact of the sheathing made of different materials and if necessary to carry out further tests.

  19. Modeling of nonlinear elastoplastic behavior after stress reversal for high strength steel

    Science.gov (United States)

    Sumikawa, S.; Ishiwatari, A.; Hiramoto, J.

    2017-09-01

    Material characteristics have significant impact on simulation of sheet metal forming. The accuracy of springback prediction depends on the estimation of strain recovery after die release. It is well known that the experimentally obtained unloading behavior for steel sheets is nonlinear stress-strain relationship, and the response during unloading and reloading shows a hysteresis loop. This behavior should be modeled by a material model and considered in FE-simulations for accurate predictions. In this study, the in-plane stress reversal tests for high strength steel were carried out to observe the elastoplastic behaviors after stress reversal. A material model that considers the nonlinear behavior was newly developed and implemented into the FEM software. The accuracy of springback prediction with the developed material model was validated by the draw bending tests and its springback simulations. The simulations with the developed material model show better agreement with the experimentally measured springback profile as compared to the other material models.

  20. Numerical modelling of unsteady 2D sheet cavitation

    NARCIS (Netherlands)

    de Lange, D.F.; de Bruin, G.J.; van Wijngaarden, L.; van Wijngaarden, L.

    1996-01-01

    Unsteady 2D sheet cavitation has been calculated by a BEM. Cubics are used to represent various quantities like the potential on the wet part of the profile, the normal velocity on the sheet, the geometry of the profile and the sheet. The growing cavity sheet, the re-entrant jet and the sheet

  1. Concentrating Solar Power Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-12-01

    This fact sheet is an overview of the Concentrating Solar Power (CSP) subprogram at the U.S. Department of Energy SunShot Initiative. CSP is a dispatchable, renewable energy option that uses mirrors to focus and concentrate sunlight onto a receiver, from which a heat transfer fluid carries the intense thermal energy to a power block to generate electricity. CSP systems can store solar energy to be used when the sun is not shining. It will help meet the nation’s goal of making solar energy fully cost-competitive with other energy sources by the end of the decade. Worldwide, CSP activity is rapidly scaling, with approximately 10 gigawatts (GW) in various stages of operation or development. In the United States alone, nearly 2 GW of CSP are in operation.

  2. Assessment of industrial wastes in mortar layers deposited on stainless steel sheets of sinks Avaliação de resíduos industriais em camadas de argamassas depositadas sobre chapas de aço inoxidável de pias

    Directory of Open Access Journals (Sweden)

    E. Gemelli

    2004-12-01

    Full Text Available This work deals with the properties of alternative mortars destined to strengthen metal sheets of sinks. The performance of these mortars was compared to that of a basic mortar made of cement, sand, and water, named standard mortar (SM. One of these mortars, named alternative mortar 2 (AM2, and composed of cement, textile residue, polyurethane, polypropylene fibers and water, was developed recently to replace the current one, named alternative mortar 1 (AM1, composed of cement, sand, polystyrene, polypropylene fibers and water. These mortars were manufactured and aged in a room in atmospheric environment for 7, 14, 28, 60 and 90 days, either with or without initial drying in a furnace. After cure of 90 days the flexion strength stress of the SM, AM1 and AM2 mortars was 5.21, 3.84, and 1.42 MPa, respectively. The SM and AM1 mortars were constituted of C-S-H phases, Ca(OH2, SiO2, AFm and AFt (monossulphate/ettringite phases. The AM2 mortar presented, apart from the compounds mentioned above, CaCO3. This compound is from the textile residue that is composed essentially of CaCO3 and Ca(OH2. The reduction in flexion strength of AM1 mortar, compared to SM mortar, is caused by the polystyrene whereas the lowering mechanical strength of the AM2 is due to both polyurethane and textile residue. Even so, its mechanical strength is acceptable because the flexion strength stress required for the industrial application is 1.0 MPa.O objetivo desse trabalho foi estudar as propriedades de argamassas alternativas usadas para reforço de chapas metálicas de pias de cozinha. O desempenho dessas argamassas foi comparado com aquele de uma argamassa básica feita de cimento, areia e água, denominada argamassa padrão (SM. Uma dessas argamassas, denominada argamassa alternativa 2 (AM2, composta de cimento, resíduo, poliuretano, fibras de polipropileno e água, foi desenvolvida recentemente para substituir a atual, chamada argamassa alternativa 1 (AM1, composta de

  3. Advanced friction modeling for sheet metal forming

    NARCIS (Netherlands)

    Hol, J.; Cid Alfaro, M.V.; de Rooij, Matthias B.; Meinders, Vincent T.

    2012-01-01

    The Coulomb friction model is frequently used for sheet metal forming simulations. This model incorporates a constant coefficient of friction and does not take the influence of important parameters such as contact pressure or deformation of the sheet material into account. This article presents a

  4. Antibubbles and fine cylindrical sheets of air

    NARCIS (Netherlands)

    Beilharz, D.; Guyon, A.; Li, E.Q.; Thoraval, Marie-Jean; Thoroddsen, S.T.

    2015-01-01

    Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a

  5. Balance velocities of the Greenland ice sheet

    DEFF Research Database (Denmark)

    Joughin, I.; Fahnestock, M.; Ekholm, Simon

    1997-01-01

    We present a map of balance velocities for the Greenland ice sheet. The resolution of the underlying DEM, which was derived primarily from radar altimetery data, yields far greater detail than earlier balance velocity estimates for Greenland. The velocity contours reveal in striking detail......, the balance map is useful for ice-sheet modelling, mass balance studies, and field planning....

  6. Sheet flow dynamics under monochromatic nonbreaking waves

    NARCIS (Netherlands)

    Dohmen-Janssen, Catarine M.; Hanes, Daniel M.

    2002-01-01

    For the first time, detailed measurements of sediment concentrations and grain velocities inside the sheet flow layer under prototype surface gravity waves have been carried out in combination with measurements of suspension processes above the sheet flow layer. Experiments were performed in a

  7. Light-sheet optimization for microscopy

    NARCIS (Netherlands)

    Wilding, D.; Pozzi, P.; Soloviev, O.A.; Vdovine, G.V.; Verhaegen, M.H.G.; Bifano, Thomas G.; Kubby, Joel; Gigan, Sylvain

    2016-01-01

    Aberrations, scattering and absorption degrade the performance light-sheet fluorescence microscopes (LSFM). An adaptive optics system to correct for these artefacts and to optimize the light-sheet illumination is presented. This system allows a higher axial resolution to be recovered over the

  8. Reinforcement for Stretch Formed Sheet Metal

    Science.gov (United States)

    Lea, J. B.; Baxter, C. R.

    1983-01-01

    Tearing of aluminum sheet metal durinng stretch forming prevented by flame spraying layer of aluminum on edges held in stretch-forming machine. Technique improves grip of machine on metal and reinforced sheet better able to with stand concentration of force in vicinity of grips.

  9. Fact Sheets on Pesticides in Schools.

    Science.gov (United States)

    National Coalition against the Misuse of Pesticides, Washington, DC.

    This document consists of a collection of fact sheets about the use of pesticides in schools and how to reduce it. The sheets are: (1) "Alternatives to Using Pesticides in Schools: What Is Integrated Pest Management?"; (2) "Health Effects of 48 Commonly Used Pesticides in Schools"; (3) "The Schooling of State Pesticide…

  10. Advanced friction modeling in sheet metal forming

    NARCIS (Netherlands)

    Hol, J.; Cid Alfaro, M.V.; Meinders, Vincent T.; Huetink, Han

    2011-01-01

    The Coulomb friction model is frequently used for sheet metal forming simulations. This model incorporates a constant coefficient of friction and does not take the influence of important parameters such as contact pressure or deformation of the sheet material into account. This article presents a

  11. Stretch bending - the plane within the sheet where strains reach the forming limit curve

    Science.gov (United States)

    Neuhauser, F. M.; Terrazas, O. R.; Manopulo, N.; Hora, P.; Van Tyne, C. J.

    2016-11-01

    Finite element analysis (FEA) was used to model the angular stretch bend test, where a strip of sheet metal is locked at both ends and a tool with a radius stretches and bends the center of the strip until failure. The FEA program used in the study was Abaqus. The FEA model was verified by experimental work using a dual phase steel (DP600) and with a simplified analytical analysis. The FEA model was used to simulate the experimental test for various frictional conditions and various radii of an upward moving tool. The primary objective of the study was to evaluate the concave-side rule, which states that during stretch bending the forming limit occurs when the strains on the concave surface plane of the bent sheet (i.e. bottom plane) reach the forming limit curve (FLC). The verification with experimental data indicates that the FEA model represents the process very well. Only conditions where failure occurred on or near the tooling are included in the results. The FEA simulations showed that the actual forming limit of the sheet occurs when the strains on the bottom plane of the sheet (i.e. concave side of the bend) reach the forming limit curve for high friction and small tool radii. For lower friction and for larger tool radii the actual forming limit occurs when strains on other planes in the sheet (i.e. mid planes or top surface plane) reach the forming limit curve. The implications of these results suggest that care must be taken in assessing forming operations when both stretch and bending occur. Although it is known that the FLC cannot predict the forming limit for small bend radii, the common assumption that the forming limit occurs when the strains for the middle thickness plane of the sheet reach the forming limit curve or that the concave side rule is often made. Understanding the limits of this assumption needs to be carefully and critically evaluated.

  12. Finite Element Structural Analysis of a Low Energy Micro Sheet Forming Machine Concept Design

    Science.gov (United States)

    Razali, A. R.; Ann, C. T.; Ahmad, A. F.; Shariff, H. M.; Kasim, N. I.; Musa, M. A.

    2017-05-01

    It is forecasted that with the miniaturization of materials being processed, energy consumption will also be ‘miniaturized’ proportionally. The aim of this researchis to design a low energy micro-sheet-forming machine for the application of thin sheet metal. A fewconcept designsof machine structure were produced. With the help of FE software, the structure is then subjected to a forming force to observe deflection in the structure for the selection of the best and simplest design. Comparison studies between mild steel and aluminium alloys 6061 were made with a view to examine the most suitable material to be used. Based on the analysis, allowable maximum tolerance was set at 2.5µm and it was found that aluminium alloy 6061 suffice to be used.

  13. Method for Parametric Shaping Architectural Free Forms Roofed with Transformed Shell Sheeting

    Science.gov (United States)

    Abramczyk, Jacek

    2017-10-01

    An innovative method for shaping attractive architectural free forms of buildings is proposed. Consistency of shell roofs and plane-walled oblique elevations of the building free forms is preserved due to utilization of specific geometrical tetrahedrons controlling general forms of entire buildings. The method proposed enables shaping roofs as warped shell forms made up of plane steel sheets folded in one direction and connected to each other along their longitudinal edges to obtain a plane strip. Next, the strip is elastically transformed into a shell shape so that a freedom of the width increments of each shell fold would be ensured. Such effective sheet shape transformations make it possible to limit the negative influence of these initial fold’s shape changes on the strength and stability of the designed roof shell. The method also allows to shape oblique plane elevation walls almost freely both individual buildings and their complex structures.

  14. Finite element modelling of deformation behaviour in incremental sheet forming of aluminium alloy

    Directory of Open Access Journals (Sweden)

    Huang Tsung-Han

    2015-01-01

    Full Text Available In this paper, the finite element method (FEM is used to study the incremental sheet forming process of pyramidal shape. The material used is aluminium alloy 5052. The tool, a hemispherical ball-head with a diameter (d = 4 mm made of HSS tool steel, is used to press down on the sheet metal causing locally plastic deformation. The comparison between spiral tool path, spiral-step tool path and z-level tool path is carried out. Moreover, the final thickness distribution is investigated. The results indicate that the minimal thickness can be found on the corner of wall angle in SPIF process. Under the same step over, spiral-step tool path can obtain the deepest depth for pyramidal shape. The maximum formability for successful forming of the pyramidal shape with depth 60 mm is wall angles 65∘.

  15. Ultra-Fine Grained Dual-Phase Steels

    Directory of Open Access Journals (Sweden)

    Matthias Militzer

    2012-10-01

    Full Text Available This paper provides an overview on obtaining low-carbon ultra-fine grained dual-phase steels through rapid intercritical annealing of cold-rolled sheet as improved materials for automotive applications. A laboratory processing route was designed that involves cold-rolling of a tempered martensite structure followed by a second tempering step to produce a fine grained aggregate of ferrite and carbides as the initial microstructure for rapid intercritical annealing. The intercritical annealing step was performed with heating and cooling rates of at least 100 °C/s and a holding time of 30 s. The intercritical temperature was selected to result in 20- 35% martensite in the final microstructures for C-Mn steels with carbon contents of 0.06, 0.12 and 0.17 wt%, respectively. The proposed processing routes produced an ultra-fine grained ferrite-martensite structure withgrain sizes of approximately 1 ?m for all three steels. The tensile strength of these ultra-fine grained dualphase steels can be increased by up to 200 MPa as compared to coarse-grained dual-phase steels while maintaining uniform elongation values. The rather narrow processing window necessary to obtain these properties was evaluated by determining the effect of intercritical annealing conditions on microstructure evolution. Further, the experimental results were confirmed with phase field simulations of austenite formation indicating that rapid heat treatment cycles are essential to obtain fine grained intercritical austenite that leads to martensite islands with sizes of 1 ?m and below in the final microstructure.

  16. Imposition of Antidumping Duty (BAMD Towards China’s Cold Rolled Coil/Sheet (CRC/S Products

    Directory of Open Access Journals (Sweden)

    Lila Pratiwi

    2013-05-01

    Full Text Available Steel industry is a strategic sector in the economy of a country. Steel industry in Indonesia has not been able to fulfill their domestic demand that is still necessary to import steel product. However, many of these imported products are sold at dumping prices, especially those from china giving rise to unfair trade. One of trade remedy measures as a result of unfair trade remedies can recover trough the imposition of antidumping duty. In 2013, Indonesia imposes antidumping duty for Cold Rolled Coil/Sheet (CRC/S from China and other countries. Imposition of antidumping duty will be analyzed descriptively with the antidumping agreement conformity. While, it cannot be denied that political factors also determine imposition of antidumping duty. It is need to use analytical theory of justice in order to enforce fair-trade

  17. Experimental study on behavior of steel channel strengthened with CFRP

    Directory of Open Access Journals (Sweden)

    Tang Hongyuan

    2017-11-01

    Full Text Available This paper describes the behaviour of axially loaded long and eccentrically loaded short thin-walled steel channels, strengthened with transversely bonded carbon fibre reinforced polymer (CFRP sheets. Seven long members, each 1400 mm long, and seven short members, each 750mmlong, were tested. The main parameters were the number of CFRP plies (one or two and the clear spacing between the CFRP strips (50, 100 or 150 mm. The effect of CFRP sheet layer and clear spacing was studied. All the ultimate load capacity of the reinforced members was improved in different extent. A maximum strength gain of 9.13% was achieved for long members with two CFRP layers and 50 mm spacing of CFRP strips. The experimental results show that the global buckling happens to all the long specimens. For short members, the maximum strength gain of 12.1% was achieved with two CFRP layers and 50 mm spacing of CFRP strips. With the exception of the most heavily reinforced (2 plies at 50 and 100 mm, local buckling was observed prior to global buckling for short members, which was completely opposite of the control specimens. Meanwhile, when the clear spacing of CFRP strips is greater than theweb height of steel channel, the transversely bonded CFRP does not have a significant improvement in buckling load capacity of the short- and long-channel components. While the clear spacing is less than the web height, the more number of CFRP layer, the more enhancement of buckling load capacity.

  18. Experimental evaluation of tool wear throughout a continuous stroke blanking process of quenched 22MnB5 ultra-high-strength steel

    Science.gov (United States)

    Vogt, S.; Neumayer, F. F.; Serkyov, I.; Jesner, G.; Kelsch, R.; Geile, M.; Sommer, A.; Golle, R.; Volk, W.

    2017-09-01

    Steel is the most common material used in vehicles’ chassis, which makes its research an important topic for the automotive industry. Recently developed ultra-high-strength steels (UHSS) provide extreme tensile strength up to 1,500 MPa and combine great crashworthiness with good weight reduction potential. However, in order to reach the final shape of sheet metal parts additional cutting steps such as trimming and piercing are often required. The final trimming of quenched metal sheets presents a huge challenge to a conventional process, mainly because of the required extreme cutting force. The high cutting impact, due to the materials’ brittleness, causes excessive tool wear or even sudden tool failure. Therefore, a laser is commonly used for the cutting process, which is time and energy consuming. The purpose of this paper is to demonstrate the capability of a conventional blanking tool design in a continuous stroke piercing process using boron steel 22MnB5 sheets. Two different types of tool steel were tested for their suitability as active cutting elements: electro-slag remelted (ESR) cold work tool steel Bohler K340 ISODUR and powder-metallurgic (PM) high speed steel Bohler S390 MICROCLEAN. A FEM study provided information about an optimized punch design, which withstands buckling under high cutting forces. The wear behaviour of the process was assessed by the tool wear of the active cutting elements as well as the quality of cut surfaces.

  19. Study of Laser Welding of HCT600X Dual Phase Steels

    Directory of Open Access Journals (Sweden)

    Švec Pavol

    2014-12-01

    Full Text Available The effects of beam power and welding speed on microstructure, microhardnes and tensile strength of HCT600X laser welded steel sheets were evaluated. The welding parameters influenced both the width and the microstructure of the fusion zone and heat affected zone. The welding process has no effect on tensile strength of joints which achieved the strength of base metal and all joints fractured in the base metal.

  20. Materials Comparison of Cutting Tools Functional Parts for Cutting of Electrical Engineering Sheets

    Directory of Open Access Journals (Sweden)

    Jan ZLÁMALÍK

    2012-06-01

    Full Text Available Paper concerns the comparison of functional materials parts of cutting tools used for the production of stator and rotor sheets in the electrical industry from point of view of their life. Alternatives and the properties of metal used for the production of stator and rotor components in electrical rotating machines are analysed. The main factors affecting the life of cutting tools of functional parts are analysed, one of the most important is the cutting tool functional parts material itself. Comparison of three variants of the cuttong tool funkcional parts material – 19 436 tool steel (chrome steel according to the Czech State Standard 41 9436, 19 830 high speed steel according to the Czech State Standard 41 9830 and a special powder metallurgy product – ledeburite tool steel Vanadis 10. Useful lifes of the functional components of individual cutting tools performances can be calculated from the theoretical lifes by their multiplying the coefficients of the tool design and the cutting edges shape complexity.

  1. Incremental electrohydraulic forming - A new approach for the manufacture of structured multifunctional sheet metal blanks

    Science.gov (United States)

    Djakow, Eugen; Springer, Robert; Homberg, Werner; Piper, Mark; Tran, Julian; Zibart, Alexander; Kenig, Eugeny

    2017-10-01

    Electrohydraulic Forming (EHF) processes permit the production of complex, sharp-edged geometries even when high-strength materials are used. Unfortunately, the forming zone is often limited as compared to other sheet metal forming processes. The use of a special industrial-robot-based tool setup and an incremental process strategy could provide a promising solution for this problem. This paper describes such an innovative approach using an electrohydraulic incremental forming machine, which can be employed to manufacture the large multifunctional and complex part geometries in steel, aluminium, magnesium and reinforced plastic that are employed in lightweight constructions or heating elements.

  2. Orthotropic Yield Criteria for Description of the Anistropy in Tension and Compression of Sheet Metals

    Science.gov (United States)

    2007-08-07

    criterion does not involve shear stres - ses, it cannot account for the continuous variation of the plastic properties between the material axes of symmetry...along a direction at angle h with the rolling direction and denote by rTh and r C h the tensile and compressive yield stres - ses, respectively. Then...modeling steels. 4.3. 2090-T3 aluminum (FCC) It was reported by Barlat et al. (1991) that for a cold rolled 2090-T3 aluminum alloy sheet under biaxial

  3. Testing and modelling of industrial tribo-systems for sheet metal forming

    DEFF Research Database (Denmark)

    Friis, Kasper Leth; Nielsen, Peter Søe; Bay, Niels

    2008-01-01

    Galling is a well-known problem in sheet metal forming of tribological difficult materials such as stainless steel. In this work new, environmentally friendly lubricants and wear resistant tool materials are tested in a laboratory environment using a strip reduction test as well as in a real....... The backstroke force and tool surface temperature are found to be highly sensitive to the initiation of galling. Furthermore the results combined with numerical investigations indicates that the level of the interface temperature is a vital factor predicting the initiation of galling....

  4. Cost and Ductility Effectiveness of Concrete Columns Strengthened with CFRP and SFRP Sheets

    Directory of Open Access Journals (Sweden)

    Khaled Abdelrahman

    2014-05-01

    Full Text Available Recently, steel fibre reinforced polymers (SFRP sheets have been introduced for the repair and rehabilitation of concrete structures. Few researchers studied the behaviour of the concrete columns wrapped with SFRP sheets; however, several critical parameters such as the cost and ductility effectiveness of the SFRP wrapped concrete columns have been lightly addressed. Thus, the main objective of this paper is to study the cost and ductility effectiveness of SFRP wrapped concrete columns and compare the results with the conventionally used carbon FRP (CFRP wrapped concrete columns. In addition, an analytical procedure to predict the cost effectiveness of SFRP wrapped concrete columns is also suggested, from which, a parametric study was conducted. The parametric study investigated the effect of the concrete strength, the number of SFRP layers, and the size and slenderness effects on the cost effectiveness of the concrete columns wrapped with SFRP sheets. The results from the cost and ductility effectiveness study indicated that the SFRP wrapped concrete columns showed enhanced performance over the CFRP wrapped concrete columns. The suggested analytical procedure proved to be a reliable and accurate method to predict the cost effectiveness parameter of SFRP wrapped concrete columns. The parametric study showed the significant impact of the investigated parameters on the cost effectiveness of concrete columns wrapped with SFRP sheets.

  5. Reinforcement of Bolted Timber Joints Using GFRP Sheets in Poplar and Pine Woods

    Directory of Open Access Journals (Sweden)

    Mehrab Madhoushi

    2013-01-01

    Full Text Available Failure in timber structures occurs mainly in crucial points such as joints areas. Therefore, the idea of using composite sheets in timber joints has been intro-duced as a method in order to increase the strength and ductility behaviour of timber joints. This research aims to study the behaviour of bolted joints in poplar and pine woods, which are reinforced by two types of GFRP sheets. A single shear bolted joint consisted of 3 timber members whose length and width were 30 cm in length and 5 cm in width. The thickness of each member was 4 cm for internal part and 2 cm for external part. The employed steel bolt was 10 cm in length and 1 cm in diameter. In this respect, one layer of GFRP sheet was used to be bonded to timber members by using epoxy resin and left between the clamps for 24 hours. They were then kept at room temperature for three weeks. Also the effect of adding a wood veneer on the reinforced joints was investigated. The tensile strength of the reinforced and control samples (un-reinforced joints was measured according to ASTM D5652-92 standard. The results show that the reinforced samples have higher tensile strength compared to that of reinforced joints, although it is not statistically signifcant. Also, two types of sheets infuence the joint behaviour as the reinforced joints display more ductility behaviour.

  6. Determination of crystallographic young’s modulus for sheet metals by in situ neutron diffraction

    Science.gov (United States)

    Vitzthum, S. J.; Hartmann, C.; Weiss, H. A.; Baumgartner, G.; Hofmann, M.; Volk, W.

    2017-09-01

    Elastic recovery is an important issue in sheet metal forming, especially in the context of the upcoming use of high strength steels due to shifted relations between Young’s modulus and strength. One important factor when it comes to elastic recovery prediction is a deep understanding for the elasto-plastic characteristics of the material. Today in general simple elastic behavior with constant Young’s modulus and Poisson’s ratio is assumed. Macroscopic analysis in standard tests shows that these assumptions are insufficient for an appropriate prediction of elastic recovery in sheet metal forming, which is why different phenomenological correlation models are derived. An experimental setup and microscopic investigation to further prove these models and to verify the approaches on another scale for sheet metals is presented within this paper. In the study microscopic deformation behavior of loading and unloading of a HC260LA sheet metal is analysed using in-situ neutron diffraction. Based on the lattice plane strains an orientation specific crystallographic Young’s modulus for different rolling directions is determined.

  7. Vibration analysis of resistance spot welding joint for dissimilar plate structure (mild steel 1010 and stainless steel 304)

    Science.gov (United States)

    Sani, M. S. M.; Nazri, N. A.; Alawi, D. A. J.

    2017-09-01

    Resistance spot welding (RSW) is a proficient joining method commonly used for sheet metal joining and become one of the oldest spot welding processes use in industry especially in the automotive. RSW involves the application of heat and pressure without neglecting time taken when joining two or more metal sheets at a localized area which is claimed as the most efficient welding process in metal fabrication. The purpose of this project is to perform model updating of RSW plate structure between mild steel 1010 and stainless steel 304. In order to do the updating, normal mode finite element analysis (FEA) and experimental modal analysis (EMA) have been carried out. Result shows that the discrepancies of natural frequency between FEA and EMA are below than 10 %. Sensitivity model updating is evaluated in order to make sure which parameters are influences in this structural dynamic modification. Young’s modulus and density both materials are indicate significant parameters to do model updating. As a conclusion, after perform model updating, total average error of dissimilar RSW plate is improved significantly.

  8. Steel designers' handbook

    CERN Document Server

    Gorenc, Branko; Tinyou, Ron

    2012-01-01

    The Revised 7th Edition of Steel Designers' Handbook is an invaluable tool for all practising structural, civil and mechanical engineers as well as engineering students at university and TAFE in Australia and New Zealand. It has been prepared in response to changes in the design Standard AS 4100, the structural Design Actions Standards, AS /ANZ 1170, other processing Standards such as welding and coatings, updated research as well as feedback from users. This edition is based on Australian Standard (AS) 4100: 1998 and subsequent amendments. The worked numerical examples in the book have been e

  9. Typhoon of Steel

    OpenAIRE

    Hamamoto, Gena

    2012-01-01

    Typhoon of Steel is a short community-based documentary film that explores the lives of two Okinawan American Kibei Nisei who served in the U.S. military as linguists in the Battle of Okinawa during World War II. While Japanese Americans on the West Coast were incarcerated in camps, these men risked their lives to prove their loyalty to America. Born in the U.S. and raised in Okinawa, their cultural and linguistic skills were a tactical asset to the military. But emotions ran high as they ...

  10. Mechanics in Steels through Microscopy

    NARCIS (Netherlands)

    Zandbergen, H.W.; Tirumalasetty, G.K.

    The goal of the study consolidated in this thesis is to understand the mechanics in steels using microscopy. In particular, the mechanical response of Transformation Induced Plasticity (TRIP) steels is correlated with their microstructures. Chapter 1 introduces the current state of the art of TRIP

  11. corrosion inhibitor for carbon steels

    African Journals Online (AJOL)

    potentiodynamic polarisation techniques. It was found that. CNSL reduces the extent of the electrochemical processes taking place on carbon steel undergoing corrosion. The corrosion rate of the carbon steel was reduced by over 92 % when only 300 ppm of CNSL was applied. This indicates that. CNSL is a potential ...

  12. Mechanics in Steels through Microscopy

    NARCIS (Netherlands)

    Tirumalasetty, G.K.

    2013-01-01

    The goal of the study consolidated in this thesis is to understand the mechanics in steels using microscopy. In particular, the mechanical response of Transformation Induced Plasticity (TRIP) steels is correlated with their microstructures. Chapter 1 introduces the current state of the art of TRIP

  13. El mundo es un paisaje sonoro

    OpenAIRE

    Rezza, Sol

    2009-01-01

    El sonido es movimiento, sin movimiento no hay sonido. Nuestras vidas cotidianas están plagadas de sonidos, el mundo es un mundo sonoro. Soundscape, paisajes sonoros, postales sonoras, ambientes sonoros son algunos de los nombres con los que se define al sonido o a la combinación de sonidos que conforman un entono específico, es decir un ambiente sonoro.

  14. Effect of V and N on the microstructure evolution during continuous casting of steel

    Science.gov (United States)

    Santillana, B.; Eskin, D. G.; Boom, R.; Katgerman, L.

    2012-01-01

    Low Carbon (LC) steel is not expected to be sensitive to hot tearing and/or cracking while microalloyed steels are known for their high cracking sensitivity during continuous casting. Experience of the Direct Sheet Plant caster at Tata Steel in Ijmuiden (the Netherlands), seems to contradict this statement. It is observed that a LC steel grade has a high risk of cracking alias hot tearing, while a High Strength Low Alloyed (HSLA) steel has a very low cracking occurrence. Another HSLA steel grade, with a similar composition but less N and V is however very sensitive to hot tearing. An extreme crack results in a breakout. A previous statistical analysis of the breakout occurrence reveals a one and a half times higher possibility of a breakout for the HSLA grade compared to the LC grade. HSLA with extra N, V shows a four times smaller possibility of breakout than LC. This study assigns the unexpected effect of the chemical composition on the hot tearing sensitivity to the role of some alloying elements such as V and N as structure refiners.

  15. Strength and formability of ultra-low-carbon Ti-IF steels[Interstitial Free

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, W.C.

    2000-04-01

    Ultra-low-carbon interstitial free (IF) steel sheets bearing Ti and/or Nb have been extensively used for automotive panels because of superior formability and nonaging properties. It is well known that the interstitial elements such as C and N play important roles in the formability. The lower the contents of the C and N in steel, the better the formability of the steel. The demands for the steel with excellent formability from automotive industry will accelerate the progress in the steelmaking process, leading to the development of the ultra-low-carbon steel. With the advent and installation of improved vacuum degassing equipment in the steelmaking process, it is now possible to consistently produce ultra-low-carbon content of 0.002 to 0.005 wt pct. It is expected that in the near future, the C and N contents can be lowered to as low as 0.001 pct or less. This study is focused on strength and formability in the extremely ultra-low-carbon IF steels containing about 0.001 pct carbon.

  16. Steels from materials science to structural engineering

    CERN Document Server

    Sha, Wei

    2013-01-01

    Steels and computer-based modelling are fast growing fields in materials science as well as structural engineering, demonstrated by the large amount of recent literature. Steels: From Materials Science to Structural Engineering combines steels research and model development, including the application of modelling techniques in steels.  The latest research includes structural engineering modelling, and novel, prototype alloy steels such as heat-resistant steel, nitride-strengthened ferritic/martensitic steel and low nickel maraging steel.  Researchers studying steels will find the topics vital to their work.  Materials experts will be able to learn about steels used in structural engineering as well as modelling and apply this increasingly important technique in their steel materials research and development. 

  17. Flexible Structural-Health-Monitoring Sheets

    Science.gov (United States)

    Qing, Xinlin; Kuo, Fuo

    2008-01-01

    A generic design for a type of flexible structural-health-monitoring sheet with multiple sensor/actuator types and a method of manufacturing such sheets has been developed. A sheet of this type contains an array of sensing and/or actuation elements, associated wires, and any other associated circuit elements incorporated into various flexible layers on a thin, flexible substrate. The sheet can be affixed to a structure so that the array of sensing and/or actuation elements can be used to analyze the structure in accordance with structural-health-monitoring techniques. Alternatively, the sheet can be designed to be incorporated into the body of the structure, especially if the structure is made of a composite material. Customarily, structural-health monitoring is accomplished by use of sensors and actuators arrayed at various locations on a structure. In contrast, a sheet of the present type can contain an entire sensor/actuator array, making it unnecessary to install each sensor and actuator individually on or in a structure. Sensors of different types such as piezoelectric and fiber-optic can be embedded in the sheet to form a hybrid sensor network. Similarly, the traces for electric communication can be deposited on one or two layers as required, and an entirely separate layer can be employed to shield the sensor elements and traces.

  18. Ice sheet margins and ice shelves

    Science.gov (United States)

    Thomas, R. H.

    1984-01-01

    The effect of climate warming on the size of ice sheet margins in polar regions is considered. Particular attention is given to the possibility of a rapid response to warming on the order of tens to hundreds of years. It is found that the early response of the polar regions to climate warming would be an increase in the area of summer melt on the ice sheets and ice shelves. For sufficiently large warming (5-10C) the delayed effects would include the breakup of the ice shelves by an increase in ice drainage rates, particularly from the ice sheets. On the basis of published data for periodic changes in the thickness and melting rates of the marine ice sheets and fjord glaciers in Greenland and Antarctica, it is shown that the rate of retreat (or advance) of an ice sheet is primarily determined by: bedrock topography; the basal conditions of the grounded ice sheet; and the ice shelf condition downstream of the grounding line. A program of satellite and ground measurements to monitor the state of ice sheet equilibrium is recommended.

  19. Influence of laser cutting on the fatigue limit of two high strength steels

    Energy Technology Data Exchange (ETDEWEB)

    Mateo, Antonio; Fargas, Gemma; Calvo, Jessica; Roa, Joan Josep [Univ. Politecnica de Catalunya, Barcelona (Spain). Dept. of Materials Science and Metallurgical Engineering

    2015-02-01

    Laser cutting is widely used in the metal industry, particularly when components of high strength steel sheets are produced. However, the roughness of cut edges produced by laser differs from that obtained by other methods, such as mechanical blanking, and this fact influences the fatigue performance. In the present investigation, specimens of two grades of high strength austenitic steels, i.e. AISI 301LN and TWIP17Mn, were cut by laser and tested in the high cycle fatigue regime to determine their corresponding fatigue limits. A series of fatigue specimens were tested without polishing and other series after a careful polishing of the cut edges, in order to assess the influence of the cut edges condition. Results indicate a significant influence of the edge roughness, more distinctive for AISI 301LN than for TWIP steel.

  20. Investigating the joining of PMMA plastic to steel by Nd:YAG laser

    Directory of Open Access Journals (Sweden)

    Andor Bauernhuber

    2012-09-01

    Full Text Available Due to the effort of weight reduction in the manufacturing of vehicles, the application and therefore the joining of different materials such as plastics and metals play more and more important role in the development of the joining processes nowadays. In this research work, the joining of PMMA plastic sheets and unalloyed steel pins was investigated. The authors applied Nd:YAG laser beam to create the bond, and tensile tests were carried out to analyse how the strength of the joint is influenced by the heating time, the penetration depth of the steel workpieces in the plastic and the surface roughness of steel. The observed bubble formation and the tearing characteristics were also studied.

  1. Investigation of the hot ductility of a high-strength boron steel

    Energy Technology Data Exchange (ETDEWEB)

    Güler, Hande, E-mail: handeguler@uludag.edu.tr; Ertan, Rukiye; Özcan, Reşat

    2014-07-01

    In this study, the high-temperature ductility behaviour of an Al–Si-coated 22MnB5 sheet was investigated. The mechanical properties of Al–Si-coated 22MnB5 boron steel were examined via hot tensile tests performed at temperatures ranging from 400 to 900 °C at a strain rate of 0.083 s{sup −1}. The deformation and fracture mechanisms under hot tensile testing were considered in relation to the testing data and to the fracture-surface observations performed via SEM. The hot ductility of the tested boron steel was observed as a function of increasing temperature and the Al–Si-coated 22MnB5 boron steel exhibited a ductility loss at 700 °C.

  2. INVESTIGATING THE JOINING OF PMMA PLASTIC TO STEEL BY Nd:YAG LASER

    Directory of Open Access Journals (Sweden)

    Tamás Markovits

    2012-10-01

    Full Text Available Due to the effort of weight reduction in the manufacturing of vehicles, the application and therefore the joining of different materials such as plastics and metals plays more and more important role in the development of the joining processes nowadays. In this research work, the joining of PMMA plastic sheets and unalloyed steel pins was investigated. The authors applied Nd:YAG laser beam to create the bond, and tensile tests were carried out to analyse how the strength of the joint is influenced by the heating time, the penetration depth of the steel workpieces in the plastic and the surface roughness of steel. The observed bubble formation and the tearing characteristics were also studied.

  3. Work-hardening of dual-phase steel

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, Florian

    2016-07-01

    Exhibiting good mechanical properties for cold-sheet forming, low-alloyed dual-phase (DP) steels are nowadays widely used for automotive applications. The composite-like microstructure of DP steels is composed of a low-carbon ductile ferrite-matrix and 10 - 60 vol.% hard martensitic inclusions. A nonlinear mean-field model and full-field finite-element simulations are applied to investigate three major topics: the influence of grain-size distribution, grain-level plasticity and derivation of an original material-model. The plastic behavior of polycrystals is assumed to be grain-size dependent in this work. The distribution of grain-sizes is taken to be lognormal. It is found that grain-size dispersion leads to a decrease of the material strength, in particular for small mean diameters around one micron. The numerical results from the mean-field model are confirmed notably well by means of a simple analytical expression. The micromechanical behavior of DP steels is investigated by full-field RVE simulations with a crystal-plasticity based ferrite-matrix and von Mises-type martensite inclusions. To examine the martensite influence, full-field simulation results of DP steels have been compared to an RVE in which martensite is substituted by ferrite. After quenching, a higher grain-boundary area covered by martensite facilitates an increased average dislocation-density. For uniaxial deformations above ∝10%, however, the grain-size dependent relation reverses. With more surrounding martensite, the local crystal-plasticity material-model exhibits hardening at a slower rate. A nonlinear mean-field model of Hashin-Shtrikman type is employed as framework for the original material-model for DP steels. The model incorporates the interaction of ferrite and martensite via incompatibility-induced long-range stresses in an averaged sense. The proposed model combines works of Ashby (1970) and Brown and Stobbs (1971a) to simulate the ferrite behavior. Based on the composite model

  4. Prediction of Forming Limit Curves from Hardness for Steels

    Science.gov (United States)

    Pavlina, Erik J.; Van Tyne, Chester J.

    2016-08-01

    This paper presents a method for predicting the strain-based forming limit curve (FLC) for steels using hardness. The stretching side (positive minor strain component) of the FLC was calculated by using a Marciniak-Kuczyński model with a non-quadratic yield function, while the drawing side (negative minor strain component) of the FLC was predicted based on the relationship between the major and minor critical strains, in accordance with the theory of maximum sheet tension for local necking. The requisite parameter that describes the plastic flow behavior (in this case, the strain hardening exponent) was calculated, based on correlations with the measured microhardness. Additionally, the strain rate sensitivity was considered in the model by using a newly developed empirical correlation between hardness and strain rate sensitivity. This hardness-based model was used to predict FLCs that demonstrate good agreement with experimental FLCs of a high-strength low-alloy steel and a dual-phase steel. Equations are provided that enable the calculation of the FLC from given hardness values for different severities of the material inhomogeneity.

  5. Cold-rolled multiphase boron steels: microstructure and mechanical properties

    Directory of Open Access Journals (Sweden)

    Fábio Dian Murari

    2015-04-01

    Full Text Available The influence of the boron concentration on phase transformation characteristics, microstructure and mechanical properties of multiphase steels was investigated using computational thermodynamics (Thermo-Calc®, dilatometry, quantitative metallography and tensile tests. Pilot scale 50 kg steel ingots were prepared in an induction furnace operating under an argon gas atmosphere with boron contents between 0 and 47 ppm. The ingots were cut into 35 mm thick blocks, which were reheated to 1250 °C for 1 h and hot rolled for seven passes to attain a thickness of 7.0 mm. The hot-rolled sheets were machined and then cold rolled to a final thickness of 1.2 mm. Continuous annealing cycles were performed in a Bähr dilatomer and in a Gleeble machine. Continuous annealing laboratory simulations showed that boron did not significantly influence the amount of austenite formed during heating and soaking steps. However, boron influenced austenite transformation during the cooling step, which reduced the amount of ferrite and increased the amount of bainite. Regarding the mechanical properties, adding boron increased strength and decreased ductility of the product. The steels with boron concentrations up to 27 ppm exhibited the greatest effect. The amount of austenite, which was calculated using Thermo-Calc®, was slightly overestimated compared with that obtained by dilatometry and metallography, particularly for soaking temperatures lower than 800 °C.

  6. Photobiology Research Laboratory (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-06-01

    This fact sheet provides information about Photobiology Research Laboratory capabilities and applications at NREL. The photobiology group's research is in four main areas: (1) Comprehensive studies of fuel-producing photosynthetic, fermentative, and chemolithotrophic model microorganisms; (2) Characterization and engineering of redox enzymes and proteins for fuel production; (3) Genetic and pathway engineering of model organisms to improve production of hydrogen and hydrocarbon fuels; and (4) Studies of nanosystems using biological and non-biological materials in hybrid generation. NREL's photobiology research capabilities include: (1) Controlled and automated photobioreactors and fermenters for growing microorganisms under a variety of environmental conditions; (2) High-and medium-throughput screening of H{sub 2}-producing organisms; (3) Homologous and heterologous expression, purification, and biochemical/biophysical characterization of redox enzymes and proteins; (4) Qualitative and quantitative analyses of gases, metabolites, carbohydrates, lipids, and proteins; (5) Genetic and pathway engineering and development of novel genetic toolboxes; and (6) Design and spectroscopic characterization of enzyme-based biofuel cells and energy conversion nanodevices.

  7. Light sheet microscopy in cell biology.

    Science.gov (United States)

    Tomer, Raju; Khairy, Khaled; Keller, Philipp J

    2013-01-01

    Light sheet-based fluorescence microscopy (LSFM) is emerging as a powerful imaging technique for the life sciences. LSFM provides an exceptionally high imaging speed, high signal-to-noise ratio, low level of photo-bleaching, and good optical penetration depth. This unique combination of capabilities makes light sheet-based microscopes highly suitable for live imaging applications. Here, we provide an overview of light sheet-based microscopy assays for in vitro and in vivo imaging of biological samples, including cell extracts, soft gels, and large multicellular organisms. We furthermore describe computational tools for basic image processing and data inspection.

  8. Crack detection methods for concrete and steel using radio frequency identification and electrically conductive materials and its applications

    Science.gov (United States)

    Morita, Koichi; Noguchi, Kazuya

    2008-03-01

    Radio Frequency IDentification (RFID) tag is a promising device for the management of products at a very low cost. Huge number of such low-cost sensors can be installed to the structure beforehand, after a disaster we can access to these sensors wirelessly and very easily. In this system, an electrically conductive paint or printed sheet is applied to a part of structure in which crack will occur. Copper wire is connected to the attachment on the structure and a RFID tag. When a crack occurs, the paint or printed sheet is broken, resulting in an increase in resistance. Crack width can be estimated by the ability of an RFID transmitter to communicate with the tag. By bending tests of concrete specimens, the relationships between concrete crack width and conductivity of the materials are examined. It is shown that the level of concrete crack width can be related to the ability of the paint or printed sheet to conduct electricity or not. This printed sheet is also applied for steel crack. By fatigue test of steel specimen with a notch, very small steel crack can be detected by this sensor.

  9. 49 CFR 192.55 - Steel pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for use...

  10. Improving the toughness of ultrahigh strength steel

    Energy Technology Data Exchange (ETDEWEB)

    Soto, Koji [Univ. of California, Berkeley, CA (United States)

    2002-01-01

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors.

  11. Innovative processing for improved electrical steel properties

    Directory of Open Access Journals (Sweden)

    Schneider, J.

    2010-10-01

    Full Text Available Electrical steel grades are the normal construction material for electrical motors and transformers because of their enhanced soft magnetic properties. One of the current trends in their production aims for increasing the silicon and/or aluminum concentration (above 3 wt % to reduce magnetic losses through increased electrical resistivity. This is very difficult to realize by conventional processing, mainly because of cracking during cold rolling. An alternative production route is proposed that raises the silicon and/or aluminum concentration by surface deposition of silicon and/or aluminum on a low-Si/low-Al steel substrate, e.g. by a short immersion in a molten Al-Si bath, followed by its diffusion into the bulk during subsequent annealing. This diffusion substantially modifies the microstructural features and therefore affects the mechanical and magnetic properties. Results of research efforts to optimize this production route and to understand the mechanisms and effects of the structural changes are presented and discussed.Los aceros eléctricos se usan, normalmente, en la construcción de motores eléctricos y transformadores debido a sus suaves propiedades magnéticas. Una de las tendencias actuales es producir aceros con contenidos mayores de silicio y/o aluminio (por encima de un 3 %, en peso para reducir las pérdidas magnéticas a través del incremento de la resistividad eléctrica. Una de las desventajas de producir este tipo de aceros con altos contenidos de silicio y/o aluminio es el agrietamiento producido en el material durante el proceso de laminado en frío. Para incrementar el contenido de silicio y/o aluminio en aceros con bajos contenidos de estos elementos de aleación, se sugiere un procedimiento alternativo de producción que se basa, fundamentalmente, en depositar un recubrimiento rico en silicio y/o aluminio, en la superficie del acero. Por ejemplo, uno de los métodos utilizados es sumergir el material en una aleaci

  12. Greenland Radar Ice Sheet Thickness Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — Two 150-MHz coherent radar depth sounders were developed and flown over the Greenland ice sheet to obtain ice thickness measurements in support of PARCA...

  13. Hydrologic Outlets of the Greenland Ice Sheet

    Data.gov (United States)

    National Aeronautics and Space Administration — The Hydrologic Outlets of the Greenland Ice Sheet data set contains GIS point shapefiles that include 891 observed and potential hydrologic outlets of the Greenland...

  14. More Fact Sheets - SEER Cancer Statistics

    Science.gov (United States)

    Cancer Statistical Fact Sheets are summaries of common cancer types developed to provide an overview of frequently-requested cancer statistics including incidence, mortality, survival, stage, prevalence, and lifetime risk.

  15. Collector/Receiver Characterization (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-08-01

    Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.

  16. Proctor Creek Boone Boulevard Fact Sheet

    Science.gov (United States)

    This fact sheet provides an overview of the Proctor Creek watershed and community, green infrastructure, the Boone Boulevard Green Street Project Conceptual Design, and the added value and application of Health Impact Assessment (HIA) to the project.

  17. Wall Insulation; BTS Technology Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Southface Energy Institute; Tromly, K.

    2000-11-07

    Properly sealed, moisture-protected, and insulated walls help increase comfort, reduce noise, and save on energy costs. This fact sheet addresses these topics plus advanced framing techniques, insulation types, wall sheathings, and steps for effective wall construction and insulation.

  18. Geometry of Thin Nematic Elastomer Sheets

    Science.gov (United States)

    Aharoni, Hillel; Sharon, Eran; Kupferman, Raz

    2014-12-01

    A thin sheet of nematic elastomer attains 3D configurations depending on the nematic director field upon heating. In this Letter, we describe the intrinsic geometry of such a sheet and derive an expression for the metric induced by general nematic director fields. Furthermore, we investigate the reverse problem of constructing a director field that induces a specified 2D geometry. We provide an explicit recipe for how to construct any surface of revolution using this method. Finally, we show that by inscribing a director field gradient across the sheet's thickness, one can obtain a nontrivial hyperbolic reference curvature tensor, which together with the prescription of a reference metric allows dictation of actual configurations for a thin sheet of nematic elastomer.

  19. The microbiome of glaciers and ice sheets

    National Research Council Canada - National Science Library

    Alexandre M Anesio; Stefanie Lutz; Nathan A M Chrismas; Liane G Benning

    2017-01-01

    .... Habitats on glaciers and ice sheets with enough liquid water to sustain microbial activity include snow, surface ice, cryoconite holes, englacial systems and the interface between ice and overridden rock/soil...

  20. HIV/AIDS Clinical Trials Fact Sheet

    Science.gov (United States)

    ... AIDS Drugs Clinical Trials Apps skip to content HIV Overview Home Understanding HIV/AIDS Fact Sheets HIV/ ... 4 p.m. ET) Send us an email HIV/AIDS Clinical Trials Last Reviewed: August 25, 2017 ...

  1. Photothermally reprogrammable buckling of nanocomposite gel sheets.

    Science.gov (United States)

    Hauser, Adam W; Evans, Arthur A; Na, Jun-Hee; Hayward, Ryan C

    2015-04-27

    Patterning deformation within the plane of thin elastic sheets represents a powerful tool for the definition of complex and stimuli-responsive 3D buckled shapes. Previous experimental methods, however, have focused on sheets that access a limited number of shapes pre-programmed into the sheet, restricting the degree of dynamic control. Here, we demonstrate on-demand reconfigurable buckling of poly(N-isopropylacrylamide-co-acrylic acid) (PNIPAM) hydrogel network films containing gold nanoparticles (AuNPs) by patterned photothermal deswelling. Predictable, easily controllable, and reversible transformations from a single flat gel sheet to numerous different three-dimensional forms are shown. Importantly, the response time is limited by poroelastic mass transport, rather than photochemical switching kinetics, enabling reconfiguration of shape on timescales of several seconds, with further increases in speed possible by reducing film thickness. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Coordinated Specialty Care Fact Sheet and Checklist

    Science.gov (United States)

    ... Checklist Share Coordinated Specialty Care Fact Sheet and Checklist Download PDF Download ePub Order a free hardcopy ... webpage: http://www.nimh.nih.gov/raise . CSC Checklist If you are interested in a CSC program, ...

  3. PV Module Reliability Research (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2013-06-01

    This National Center for Photovoltaics sheet describes the capabilities of its PV module reliability research. The scope and core competencies and capabilities are discussed and recent publications are listed.

  4. Drinking Water Fact Sheet: Coliform Bacteria

    OpenAIRE

    Mesner, Nancy; Daniels, Barbara

    2010-01-01

    This fact sheet provides information about coliform bacteria. Including sections about what coliform bacteria is, how it enters drinking water, health concerns from exposure, drinking water standards, and how to treat drinking water that contains coliforms.

  5. Nanotechnology for Site Remediation: Fact Sheet

    Science.gov (United States)

    This fact sheet presents a snapshot of nanotechnology and its current uses in remediation. It presents information to help site project managers understand the potential applications of this group of technologies at their sites.

  6. Advancing Concentrating Solar Power Research (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-02-01

    Researchers at the National Renewable Energy Laboratory (NREL) provide scientific, engineering, and analytical expertise to help advance innovation in concentrating solar power (CSP). This fact sheet summarizes how NREL is advancing CSP research.

  7. Laser bending process of preloaded sheet metal

    Directory of Open Access Journals (Sweden)

    Xu Lang

    2015-01-01

    Full Text Available Laser bending process of preloaded sheet metal was reviewed on theoretical researches, forming experiments, numerical simulations and material performance studies of formed sheets. Considering the pre-bending platforms that used in the forming experiments can only work on few simple pre-bending types and small sized sheet metals, a large and flexible pre-bending platform was developed by authors. Experiments were done on this platform. The results of experiments showed that different pre-bending types lead to bending sheet metals into different curved shapes and large sized structure components of flight vehicles can be formed using this process. Based on the current research status, further developments and challenges of this process are discussed.

  8. Hardness analysis of welded joints of austenitic and duplex stainless steels

    Science.gov (United States)

    Topolska, S.

    2016-08-01

    Stainless steels are widely used in the modern world. The continuous increase in the use of stainless steels is caused by getting greater requirements relating the corrosion resistance of all types of devices. The main property of these steels is the ability to overlap a passive layer of an oxide on their surface. This layer causes that they become resistant to oxidation. One of types of corrosion-resistant steels is ferritic-austenitic steel of the duplex type, which has good strength properties. It is easily formable and weldable as well as resistant to erosion and abrasive wear. It has a low susceptibility to stress-corrosion cracking, to stress corrosion, to intercrystalline one, to pitting one and to crevice one. For these reasons they are used, among others, in the construction of devices and facilities designed for chemicals transportation and for petroleum and natural gas extraction. The paper presents the results which shows that the particular specimens of the ][joint representing both heat affected zones (from the side of the 2205 steel and the 316L one) and the weld are characterized by higher hardness values than in the case of the same specimens for the 2Y joint. Probably this is caused by machining of edges of the sections of metal sheets before the welding process, which came to better mixing of native materials and the filler metal. After submerged arc welding the 2205 steel still retains the diphase, austenitic-ferritic structure and the 316L steel retains the austenitic structure with sparse bands of ferrite σ.

  9. Resistance of trip 800 steels in a sour environment containing H{sub 2}S

    Energy Technology Data Exchange (ETDEWEB)

    Sojka, J.; Vodarek, V.; Vanova, P.; Schindler, I.; Wenglorzova, A.; Filus, F. [VSB-TU Ostrava, Faculty of Metallurgy and Materials Engineering, 17. listopadu 15, 708 33, Ostrava (Czech Republic); Kander, L. [Materialovy a metalurgicky vyzkum, s.r.o., Pohranicni 31, 706 02 Ostrava-Vitkovice (Czech Republic)

    2011-07-15

    We have evaluated the resistance of two samples of TRIP 800 steel prepared under laboratory conditions at the Faculty of Metallurgy and Materials Engineering (FMME) VSB (Technical University of Ostrava, Czech Republic) in a sour environment containing H{sub 2}S. The first steel investigated had a C-Mn-Si composition, and the second steel had a C-Mn-Si-Al composition. Both TRIP steels were characterized using the yield strength in the range 420 to 450 MPa and tensile strength in the range 880 to 900 MPa. The TRIP steel samples were in the form of sheets with a thickness of 1.5 mm. The residual austenite content was 11% and 13%, respectively, in the two steels studied. The resistance to hydrogen embrittlement was evaluated in a sour environment that contained hydrogen sulphide using hydrogen-induced cracking (HIC) and sulphide stress cracking (SSC) tests performed in accordance with NACE standards. Both TRIP 800 steels showed a high resistance to hydrogen embrittlement, and no SSC cracks were observed. Some cracking arising from HIC was observed in both steels. The measured parameters showed some variation; in some cases they were lower than recommended limits, but in other cases the measured parameters were higher (e.g., the crack length ratio was up to 70%). The cracks initiated preferentially at non-metallic inclusions, either at elongated manganese sulphide particles, or at oxide stringers that were rich in Al. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Methods of making bainitic steel materials

    Energy Technology Data Exchange (ETDEWEB)

    Bakas, Michael Paul; Chu, Henry Shiu-Hung; Zagula, Thomas Andrew; Langhorst, Benjamin Robert

    2018-01-16

    Methods of making bainitic steels may involve austenitizing a quantity of steel by exposing the quantity of steel to a first temperature. A composition of the quantity of steel may be configured to impede formation of non-bainite ferrite, pearlite, and Widmanstatten ferrite. The quantity of steel may be heat-treated to form bainite by exposing the quantity of steel to a second, lower temperature. The second, lower temperature may be stabilized by exposing the quantity of steel to the second, lower temperature in the presence of a thermal ballast.

  11. Stahlschüssel key to steel

    CERN Document Server

    Wegst, W S

    2016-01-01

    The Key to Steel (Stahlschlüssel/Stahlschluessel) cross reference book will help you to decode / decipher steel designations and find equivalent materials worldwide. The 2016 edition includes more than 70,000 standard designations and trade names from approximately 300 steelmakers and suppliers. Presentation is trilingual: English, French, and German. Materials covered include structural steels, tool steels, valve steels, high temperature steels and alloys, stainless and heat-resisting steels, and more. Standards and designations from 25 countries are cross-referenced.

  12. Adolescence and abstinence. Fact sheet.

    Science.gov (United States)

    1997-01-01

    This fact sheet presents statistics on adolescent sexual activity in the US and a brief description of comprehensive sex education and abstinence-only programs. The statistical profile indicates that over 50% of teenagers are virgins until at least 17 years of age. 20% of boys and 24% of girls are virgins by the age of 20 years. Only 6.9% of men 18-59 years old and 21% of women 18-59 years old were still virgins on their wedding night. However, among a sample of high school students, over 33% of male and female virgins had engaged in some form of heterosexual genital sexual activity in the preceding year. 29% of virgins had masturbated a partner of the opposite gender. 31% had been masturbated by a partner of the opposite gender. 9% had engaged in fellatio with ejaculation with a partner of the opposite gender. 10% had engaged in cunnilingus with a partner of the opposite gender. 1% had engaged in anal intercourse with a partner of the opposite gender. Comprehensive sex education aims to help adolescents postpone sexual intercourse until they are ready for mature relationships by helping them develop interpersonal skills to resist premature sexual involvement. Messages include information about sexual abstinence, contraception, and safer sex. A 1993 study found that sexual abstinence messages were one of the most frequently covered topics in state curricula and guidelines. Other key topics were families, decision making, and sexually transmitted diseases including AIDS. The least covered topics were sexual identity, shared sexual behavior, sexual response, masturbation, and abortion. There were only six studies of abstinence-only programs, of which at least two showed no impact on sexual or contraceptive behavior. The National Institute of Health says that abstinence-only programs ignore the success of other programs and conflict with science.

  13. Exposure age and ice-sheet model constraints on Pliocene East Antarctic ice sheet dynamics

    OpenAIRE

    Yamane, Masako; Yokoyama, Yusuke; Abe-Ouchi, Ayako; Obrochta, Stephen; Saito, Fuyuki; Moriwaki, Kiichi; Matsuzaki, Hiroyuki

    2015-01-01

    The Late Pliocene epoch is a potential analogue for future climate in a warming world. Here we reconstruct Plio-Pleistocene East Antarctic Ice Sheet (EAIS) variability using cosmogenic nuclide exposure ages and model simulations to better understand ice sheet behaviour under such warm conditions. New and previously published exposure ages indicate interior-thickening during the Pliocene. An ice sheet model with mid-Pliocene boundary conditions also results in interior thickening and suggests ...

  14. Shape change in mouthguard sheets during thermoforming.

    Science.gov (United States)

    Takahashi, Mutsumi; Koide, Kaoru; Satoh, Yoshihide; Iwasaki, Shin-Ichi

    2016-10-01

    The purpose of this study was to identify changes in sheet shape during thermoforming and the effect of the model position in the molding machine on fabricated mouthguard thickness. Ethylene vinyl acetate mouthguard sheets (3.8 mm thick) were used that had cross-stripes (10 × 10 mm), and the anteroposterior and bilateral lengths were used for measurements. Two forming machines were used: a vacuum- and a pressure-forming machine, and two heating conditions were investigated that defined as the time when sagging of the softened sheet was 15 mm (H-15) and 20 mm (H-20) below the clamp, and the length of each cross-stripes was measured. The area of each lattice was calculated using Bretschneider's formula to compare changes in sheet shape for each condition. Next, mouthguards were molded by forming machine where the working model was positioned under two different conditions: with the model anterior centered in the forming unit and with the model centered. The sheet thickness after fabrication was determined for the incisal and the molar portion, and dimensional measurements were obtained using a measuring device. Differences in the thickness were analyzed by two-way analysis of variance (anova). In both molding machines, the change in the area under H-20 was greater than H-15. While the increase in area tended to expand from the center of the sheet in concentric circles, the difference between the central and surrounding areas was only approximately 5%. For both molding machines, differences in thickness after molding due to setting position of the model were not observed. The results showed that shape changes of the sheet during thermoforming tend to concentrically and almost uniformly expand from the center and that it is important to center the sheet and the model when positioning the model in the forming unit. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Preparation and transplantation of photoreceptor sheets.

    Science.gov (United States)

    Huang, J C; Ishida, M; Hersh, P; Sugino, I K; Zarbin, M A

    1998-06-01

    Photoreceptor (PR) transplantation may be a treatment for blindness secondary to PR degeneration. We studied different technical aspects of PR-sheet preparation. Geographic variation in the thickness of the cat PR layer (from the outer segments to the outer plexiform layer) and inner retina (width of the remainder of the retina) was studied. PR sheets (cat and human) were prepared through gelatin embedding and subsequent vibratoming or excimer laser ablation. Cat PR sheets were evaluated after transplantation. The thickness of the cat PR layer and inner retina varied in different regions. The superior central retina, including the area centralis, was thickest (PR layer: 115-123 microm, entire retina: 225-230 microm, in fixed tissue). The peripheral retina was approximately 40% thinner than the center. Fresh retina was approximately 7.9% thicker than the fixed retina. Both vibratomy and excimer laser ablation removed the inner retina, leaving a PR-layer sheet with good morphology. To produce good quality PR sheets with vibratomy, use of different gelatin concentrations (2% to 35%) at various stages of sheet preparation was crucial. To produce PR sheets of uniform thickness with excimer laser ablation, control of fluid on the retinal surface was critical. Twenty-four hours after PR transplantation surgery, donor PR cells were well oriented and in close contact with host retinal pigment epithelial cells. Gelatin supporting the transplant dissolved as early as 100 min after surgery. We confirmed and expanded the work of previous investigators and showed that cat and human PR sheets can be manufactured using vibratomy or excimer laser ablation. This preparation provides a well oriented and organized PR cell layer after transplantation.

  16. Modelling fracture in ferritic steel

    CERN Document Server

    Smith, G

    2002-01-01

    Results from mathematical models and computer simulations of fracture in polycrystalline steels are presented for a range of temperatures. The proportions of intergranular and intragranular failure predicted are compared with experimental results for brittle fracture, ductile fracture and in the transition region. Interactive software to create two-dimensional polycrystalline models, which allow a range of physical to be varied independently, is described. The results include those for model materials chosen to match steels used by the power generation industry. The models simulate segregation and cavitation effects in steel and fracture of weldments and their associated heat-affected zones.

  17. Cold-formed steel design

    CERN Document Server

    Yu, Wei-Wen

    2010-01-01

    The definitive text in the field, thoroughly updated and expanded Hailed by professionals around the world as the definitive text on the subject, Cold-Formed Steel Design is an indispensable resource for all who design for and work with cold-formed steel. No other book provides such exhaustive coverage of both the theory and practice of cold-formed steel construction. Updated and expanded to reflect all the important developments that have occurred in the field over the past decade, this Fourth Edition of the classic text provides you with more of the detailed, up-to-the-minute techni

  18. Steel fiber replacement of mild steel in prestressed concrete beams

    Science.gov (United States)

    2010-10-01

    In traditional prestressed concrete beams, longitudinal prestressed tendons serve to resist bending moment and : transverse mild steel bars (or stirrups) are used to carry shear forces. However, traditional prestressed concrete I-beams : exhibit earl...

  19. High-strength, low-alloy steels.

    Science.gov (United States)

    Rashid, M S

    1980-05-23

    High-strength, low-alloy (HSLA) steels have nearly the same composition as plain carbon steels. However, they are up to twice as strong and their greater load-bearing capacity allows engineering use in lighter sections. Their high strength is derived from a combination of grain refinement; precipitation strengthening due to minor additions of vanadium, niobium, or titanium; and modifications of manufacturing processes, such as controlled rolling and controlled cooling of otherwise essentially plain carbon steel. HSLA steels are less formable than lower strength steels, but dualphase steels, which evolved from HSLA steels, have ferrite-martensite microstructures and better formability than HSLA steels of similar strength. This improved formability has substantially increased the utilization potential of high-strength steels in the manufacture of complex components. This article reviews the development of HSLA and dual-phase steels and discusses the effects of variations in microstructure and chemistry on their mechanical properties.

  20. 2169 steel waveform experiments.

    Energy Technology Data Exchange (ETDEWEB)

    Furnish, Michael David; Alexander, C. Scott; Reinhart, William Dodd; Brown, Justin L.

    2012-11-01

    In support of LLNL efforts to develop multiscale models of a variety of materials, we have performed a set of eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn, balance predominantly Fe). These experiments provided carefully controlled shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were included in this experiment set to increase the utility of the data set, as were samples ranging in thickness from 1 to 5 mm. Target physical phenomena included the elastic/plastic transition (Hugoniot elastic limit), the Hugoniot, any phase transition phenomena, and the release path (windowed and free-surface). The Hugoniot was found to be nearly linear, with no indications of the Fe phase transition. Releases were non-hysteretic, and relatively consistent between 3- and 5-mmthick samples (the 3 mm samples giving slightly lower wavespeeds on release). Reshock tests with explosively welded impactors produced clean results; those with glue bonds showed transient releases prior to the arrival of the reshock, reducing their usefulness for deriving strength information. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allows release information to be determined from these free surface samples. The sample strength appears to increase with stress from ~1 GPa to ~ 3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model.