Tensile properties and drawability of thin bimetallic aluminum-scandium-zirconium / stainless steel foils and monometallic Al-Sc-Zr fabricated by magnetron sputtering

Al-Sc-Zr alloys are interesting for the production of high strength micro components by micro deep drawing. These alloys show a good hardenability due to the formation of nanometer-scale spheroidal Al3(Sc, Zr) precipitates, which are highly coherent with the aluminum matrix. However, the formation of these precipitates in Al-Sc-Zr foils fabricated by conventional metallurgical methods dramatically reduces their ductility and drawability. In this work, magnetron sputtering was used to produce Al-Sc-Zr foils and Al-Sc-Zr / stainless steel bimetallic foils which are nearly free of these precipitates. Tensile tests were carried out to measure and compare the mechanical properties of monometallic Al-Sc-Zr foils and bimetallic Al-Sc-Zr / stainless steel foils deposited with varying plasma target powers and containing different volume fractions (layer thickness) of Al-Sc-Zr. Micro deep drawing was used to determine the drawability of selected monometallic and bimetallic foils. The results show that the density of monometallic Al-Sc-Zr foils can be improved significantly by increasing the DC target power and by using the high power impulse magnetron sputtering (HiPIMS) technology, resulting in foils with higher ductility. Bimetallic foils achieved higher strength and ductility than monometallic Al-Sc-Zr foils. Their mechanical properties vary with the target power and the volume fraction (thickness) of Al-Sc-Zr. The limit drawing ratio of HiPIMS deposited monometallic foil was 1.7 or 1.8 depending on the side of the foil facing the die, whereas a limit drawing ratio of 1.9 was observed for bimetallic foils.

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On the limit drawing ratio of magnetron sputtered aluminium–scandium foils within micro deep drawing

Production Engineering ◽

10.1007/s11740-010-0229-2 ◽

2010 ◽

Vol 4 (5) ◽

pp. 451-456 ◽

Cited By ~ 8

Author(s):

Frank Vollertsen ◽

Zhenyu Hu ◽

Heinz-Rolf Stock ◽

Bernd Koehler

Keyword(s):

Deep Drawing ◽

Drawing Ratio ◽

Limit Drawing Ratio ◽

Micro Deep Drawing

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ALZ 305

Alloy Digest ◽

10.31399/asm.ad.ss0762 ◽

1999 ◽

Vol 48 (9) ◽

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Corrosion Resistance ◽

Austenitic Stainless Steel ◽

Physical Properties ◽

Deep Drawing ◽

Heat Treating ◽

Intermediate Annealing ◽

Good Corrosion Resistance

Abstract ALZ 305 is an austenitic stainless steel with excellent formability and good corrosion resistance, toughness, and mechanical properties. The higher amount of nickel in this grade enables high deep-drawing deformation without intermediate annealing. This datasheet provides information on composition, physical properties, and elasticity. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-762. Producer or source: ALZ nv.

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Experimental Investigation on Micro Deep Drawing of Stainless Steel Foils with Different Microstructural Characteristics

Chinese Journal of Mechanical Engineering ◽

10.1186/s10033-021-00556-5 ◽

2021 ◽

Vol 34 (1) ◽

Author(s):

Jingwei Zhao ◽

Tao Wang ◽

Fanghui Jia ◽

Zhou Li ◽

Cunlong Zhou ◽

...

Keyword(s):

Stainless Steel ◽

Deep Drawing ◽

Annealing Temperature ◽

Localized Deformation ◽

Microstructural Characteristics ◽

Height Profile ◽

Annealing Temperatures ◽

Micro Deep Drawing ◽

Profile Distribution

AbstractIn the present work, austenitic stainless steel (ASS) 304 foils with a thickness of 50 µm were first annealed at temperatures ranging from 700 to 1100 ℃ for 1 h to obtain different microstructural characteristics. Then the effects of microstructural characteristics on the formability of ASS 304 foils and the quality of drawn cups using micro deep drawing (MDD) were studied, and the mechanism involved was discussed. The results show that the as-received ASS 304 foil has a poor formability and cannot be used to form a cup using MDD. Serious wrinkling problem occurs on the drawn cup, and the height profile distribution on the mouth and the symmetry of the drawn cup is quite non-uniform when the annealing temperature is 700 ℃. At annealing temperatures of 900 and 950 ℃, the drawn cups are both characterized with very few wrinkles, and the distribution of height profile, symmetry and mouth thickness are uniform on the mouths of the drawn cups. The wrinkling becomes increasingly significant with a further increase of annealing temperature from 950 to 1100 ℃. The optimal annealing temperatures obtained in this study are 900 and 950 ℃ for reducing the generation of wrinkling, and therefore improving the quality of drawn cups. With non-optimized microstructure, the distribution of the compressive stress in the circumferential direction of the drawn foils becomes inhomogeneous, which is thought to be the cause of the occurrence of localized deformation till wrinkling during MDD.

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Understanding Size Effects and Forming Limits in the Micro-Stamping of Industrial Stainless Steel Foils

Metals ◽

10.3390/met11010038 ◽

2020 ◽

Vol 11 (1) ◽

pp. 38

Author(s):

Matthias Weiss ◽

Peng Zhang ◽

Michael P. Pereira ◽

Bernard F. Rolfe ◽

Daniel E. Wilkosz ◽

...

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Size Effects ◽

Bipolar Plate ◽

Forming Limits ◽

Tool Profile ◽

Steel Processing ◽

The Individual ◽

Stainless Steel Foils ◽

Steel Foils

This study investigates the effect of grain size and composition on the material properties and forming limits of commercially supplied stainless steel foil for bipolar plate manufacture via tensile, stretch forming and micro-stamping trials. It is shown that in commercially supplied stainless steel the grain size can vary significantly and that ‘size effects’ can be influenced by prior steel processing and composition effects. While the forming limits in micro-stamping appear to be directly linked to the plane strain forming limits of the individual stainless steel alloys, there was a clear effect of the tensile anisotropy. In contrast to previous studies, forming severity and the likelihood of material failure did not increase with a decreasing channel profile radius. This was related to inaccuracies of the forming tool profile shape.

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Modified Monkman–Grant relationship for austenitic stainless steel foils

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2012.08.048 ◽

2013 ◽

Vol 433 (1-3) ◽

pp. 74-79 ◽

Cited By ~ 12

Author(s):

Hassan Osman Ali ◽

Mohd Nasir Tamin

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Stainless Steel Foils ◽

Steel Foils

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Amorphous Silicon TFTs on Steel-Foil Substrates

MRS Proceedings ◽

10.1557/proc-424-65 ◽

1996 ◽

Vol 424 ◽

Cited By ~ 10

Author(s):

S. D. Theiss ◽

S. Wagner

Keyword(s):

Stainless Steel ◽

Leakage Currents ◽

Action Current ◽

Insulating Layer ◽

Stainless Steel Foil ◽

Current Voltage ◽

Stainless Steel Foils ◽

Steel Foils ◽

Current Behavior

AbstractWe describe the successful fabrication of device-quality a-Si:H thin-film transistors (TFTs) on stainless-steel foil substrates. These TFTs demonstrate that transistor circuits can be made on a flexible, non-breakable substrate. Such circuits could be used in reflective or emissive displays, and in other applications that require rugged macroelectronic circuits.Two inverted TFT structures have been made, using 200 gim thick stainless steel foils with polished surfaces. In the first structure we used the substrate as the gate and utilized a homemade mask set with very large feature sizes: L = 45 μm; W = 2.5 mm. The second, inverted staggered, structure used a 9500 Å a-SiNx:H passivating/insulating layer deposited on the steel to enable the use of isolated gates. For this structure we used a mask set which is composed of TFTs with much smaller feature sizes. Both TFT structures exhibit transistor action. Current-voltage characterization of the TFTs with the inverted staggered structure shows typical on/off current ratios of 107, leakage currents on the order of 10-12 A, good linear and saturation current behavior, and channel mobilities of 0.5 cm2/V·sec. These characteristics clearly identify the TFTs grown on stainless steel foil as being of device quality.

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