CONTOUR PRESENTATION OF PLASTIC STRAIN OF A SQUARE ALUMINIUM SHEET BLANK IN CONDITIONS OF IMPLEMENTATION OF A SHALLOW DRAWING PROCESS.

As von Mises yield criterion and associated flow rule (AFR) are widely applied in metal forming field, a semitotal deformation consistent relationship between the stress and plastic strain components and the rule of dimensional changes of metal forming processes in a plane-stress state are obtained on the basis of them in this paper. The deduced consistent relationship may be easily used in forming interval of the workpiece. And the rule of dimensional changes can be understood through three plastic strain incremental circles on which the critical points can be easily determined on the same basis. Analysis of stress and plastic strain evolution of aluminum warm deep drawing process is conducted, and the advantage of nonisothermal warm forming process is revealed, indicating that this method has the potential in practical large deformation applications.

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Physical Modelling and Numerical Simulation of the Deep Drawing Process of a Box-Shaped Product Focused on Material Limits Determination

Metals ◽

10.3390/met9101058 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1058 ◽

Cited By ~ 3

Author(s):

Miroslav Tomáš ◽

Emil Evin ◽

Ján Kepič ◽

Juraj Hudák

Keyword(s):

Plastic Strain ◽

Deep Drawing ◽

Scaling Laws ◽

Strain Ratio ◽

Physical Models ◽

Scale Model ◽

Drawing Process ◽

Plastic Strain Ratio ◽

Thickness Change ◽

Deep Drawing Process

Similitude theory helps engineers and scientists to accurately predict the behaviors of real systems through the application of scaling laws to the experimental results of a scale model related to the real system by similarity conditions. The theory was applied when studying the deep drawing process of a bathtub made from cold rolled low carbon aluminum-killed steel from the point of view of material limits. The bathtub model was created on the basis of geometric, physical, and mechanical similarity on a scale of 1:5. Thus, simulations and physical models were created. The simulation model was used to verify the combination yield locus/hardening law on the basis of comparing the thickness change. As a result, Hill 48/Krupkowski showed the minimal deviation by comparing data evaluated from numerical simulations and that measured on the physical model. Additionally, material anisotropy was modelled when virtual materials were defined from experimentally measured values of the plastic strain ratio. As an outcome, extra deep drawing quality steel with an average plastic strain ratio of rm ≥ 1.47 and an average strain hardening exponent of nm ≥ 0.23 must be used for the deep drawing of the bathtub.

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Deep Drawing Process of the AISI 304 Stainless Steel Cup: Interaction Between Design Tools and Kinetic of Plastic Strain Induced Martensite

Solid Mechanics and Its Applications - IUTAM Symposium on Multiscale Modeling and Characterization of Elastic-Inelastic Behavior of Engineering Materials ◽

10.1007/978-94-017-0483-0_49 ◽

2004 ◽

pp. 405-412

Author(s):

Zoubeir Tourki ◽

Mohamed Cherkaoui

Keyword(s):

Stainless Steel ◽

Plastic Strain ◽

Deep Drawing ◽

304 Stainless Steel ◽

Design Tools ◽

Drawing Process ◽

Aisi 304 Stainless Steel ◽

Aisi 304 ◽

Deep Drawing Process ◽

Strain Induced Martensite

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Analysis of Stress and Strain in the Equal Channel Angular Drawing Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.526.19 ◽

2006 ◽

Vol 526 ◽

pp. 19-24 ◽

Cited By ~ 2

Author(s):

Javier León ◽

C.J. Luis-Pérez

Keyword(s):

Plastic Strain ◽

Cross Section ◽

Three Dimensional ◽

Longitudinal Axis ◽

Wire Drawing ◽

Stress And Strain ◽

Drawing Process ◽

The Cross ◽

High Plastic Strain ◽

High Plastic

The equal channel angular drawing (ECAD) process is an innovative method to obtain materials with high plastic strain in a continuous way. This deformation is higher than the deformation achieved by a conventional wire drawing process, for the same reduction of the cross section, so if an adequate thermal treatment is employed later, it could be possible to obtain an initial material with high value that could be useful in conventional manufacturing processes. This process consists in drawing a material through a die where two circular channels intersect at an angle between 90º and 135º. In this work a study using finite element of the plastic strain and the stresses that appear for one aluminium alloy AA-1370 has been carried out. Two ECAD passes have been made, where for the second pass the billet has been rotated 180º along the longitudinal axis. Finally, a calibrated pass has been carried out in order to obtain the billet with homogeneous dimensions in all the cross section. All the simulations have been calculated at room temperature and by using good conditions of lubrication. In order to perform the FEM simulations, a three dimensional geometry has been used. To analyze by FEM the second ECAD pass and the calibration pass, the deformations and stresses achieved in the previous passes have been taken into consideration. This has been done with the aim of achieving higher accuracy. Moreover, a comparative analysis with experimental results has been carried out.

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Plastic Deformation in Microtomed Sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066346 ◽

1971 ◽

Vol 29 ◽

pp. 458-459

Author(s):

J. Temple Black

Keyword(s):

Plastic Deformation ◽

Plastic Strain ◽

Applied Stress ◽

Elastic Strain ◽

High Strain ◽

Tool Material ◽

Cutting Edge ◽

Material Structure ◽

Geometrical Constraints

The output of the ultramicrotomy process with its high strain levels is dependent upon the input, ie., the nature of the material being machined. Apart from the geometrical constraints offered by the rake and clearance faces of the tool, each material is free to deform in whatever manner necessary to satisfy its material structure and interatomic constraints. Noncrystalline materials appear to survive the process undamaged when observed in the TEM. As has been demonstrated however microtomed plastics do in fact suffer damage to the top and bottom surfaces of the section regardless of the sharpness of the cutting edge or the tool material. The energy required to seperate the section from the block is not easily propogated through the section because the material is amorphous in nature and has no preferred crystalline planes upon which defects can move large distances to relieve the applied stress. Thus, the cutting stresses are supported elastically in the internal or bulk and plastically in the surfaces. The elastic strain can be recovered while the plastic strain is not reversible and will remain in the section after cutting is complete.

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Comparison of Substructures Between Uniaxial and Biaxial Deformation in 1100-0 Aluminum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096989 ◽

1981 ◽

Vol 39 ◽

pp. 52-53

Author(s):

D. L. Rohr ◽

S. S. Hecker

Keyword(s):

Plastic Strain ◽

Cell Walls ◽

Room Temperature ◽

Mechanical Response ◽

Biaxial Tension ◽

Initial Deformation ◽

Uniaxial Deformation ◽

Biaxial Deformation ◽

Stress States ◽

Comprehensive Study

As part of a comprehensive study of microstructural and mechanical response of metals to uniaxial and biaxial deformations, the development of substructure in 1100 A1 has been studied over a range of plastic strain for two stress states.Specimens of 1100 aluminum annealed at 350 C were tested in uniaxial (UT) and balanced biaxial tension (BBT) at room temperature to different strain levels. The biaxial specimens were produced by the in-plane punch stretching technique. Areas of known strain levels were prepared for TEM by lapping followed by jet electropolishing. All specimens were examined in a JEOL 200B run at 150 and 200 kV within 24 to 36 hours after testing.The development of the substructure with deformation is shown in Fig. 1 for both stress states. Initial deformation produces dislocation tangles, which form cell walls by 10% uniaxial deformation, and start to recover to form subgrains by 25%. The results of several hundred measurements of cell/subgrain sizes by a linear intercept technique are presented in Table I.

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