Cyclic stress-strain data analysis under biaxial tensile stress state

Numerical process design leads to cost and time savings in sheet metal forming processes. Therefore, a modeling of the material behavior is required to map the flow properties of sheet metal. For the identification of current yield criteria, the yield strength and the hardening behavior as well as the Lankford coefficients are taken into account. By considering the anisotropy as a function of rolling direction and stress state, the prediction quality of anisotropic materials is improved by a more accurate modeling of the yield locus curve. According to the current state of the art, the layer compression test is used to determine the corresponding Lankford coefficient for the biaxial tensile stress state. However, the test setup and the test procedure is quite challenging compared to other tests for the material characterization. Due to this, the test is only of limited suitability if only the Lankford coefficient has to be determined. In this contribution, a simplified test is presented. It is a reduction of the layer compression test to one single sheet layer. So the Lankford coefficient for the biaxial tensile stress state can be analyzed with a significantly lower test effort. The results prove the applicability of the proposed test for an easy and time efficient characterization of the biaxial Lankford coefficient.

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Experimental Thermomechanical Analysis of Elastomers Under Uni- and Biaxial Tensile Stress State

Experimental Mechanics ◽

10.1007/s11340-013-9820-8 ◽

2013 ◽

Vol 54 (4) ◽

pp. 653-663 ◽

Cited By ~ 15

Author(s):

U. D. Çakmak ◽

Z. Major

Keyword(s):

Stress State ◽

Tensile Stress ◽

Thermomechanical Analysis ◽

Biaxial Tensile ◽

Biaxial Tensile Stress

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Calculations of energy band structure and mobility in critical bandgap strained Ge1-xSnx based on Sn component and biaxial tensile stress modulation

Acta Physica Sinica ◽

10.7498/aps.67.20171969 ◽

2018 ◽

Vol 67 (2) ◽

pp. 027101

Author(s):

Di Lin-Jia ◽

Dai Xian-Ying ◽

Song Jian-Jun ◽

Miao Dong-Ming ◽

Zhao Tian-Long ◽

...

Keyword(s):

Band Structure ◽

Tensile Stress ◽

Energy Band ◽

Energy Band Structure ◽

Biaxial Tensile ◽

Biaxial Tensile Stress

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Digital recording and automatic computation of film tensile stress–strain data

Journal of Applied Polymer Science ◽

10.1002/app.1961.070051705 ◽

1961 ◽

Vol 5 (17) ◽

pp. 527-533 ◽

Cited By ~ 1

Author(s):

Gordon D. Patterson ◽

Thomas D. Mecca

Keyword(s):

Tensile Stress ◽

Digital Recording ◽

Stress Strain ◽

Automatic Computation ◽

Strain Data

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Deformation Plasticity Failure Assessment Diagram (DPFAD) for Materials With Non-Ramberg-Osgood Stress-Strain Curves

Journal of Pressure Vessel Technology ◽

10.1115/1.2842134 ◽

1995 ◽

Vol 117 (4) ◽

pp. 346-356 ◽

Cited By ~ 5

Author(s):

J. M. Bloom

Keyword(s):

Tensile Stress ◽

Manganese Steel ◽

Uniaxial Tensile ◽

J Integral ◽

Stress Strain ◽

Failure Assessment Diagram ◽

Failure Assessment ◽

Strain Data ◽

Deformation Plasticity ◽

Uniaxial Tensile Stress

This paper presents a brief history of the evolution of the Central Electricity Generating Board’s (CEGB) R-6 failure assessment diagram (FAD) procedure used in assessing defects in structural components. The reader is taken from the original CEGB R-6 FAD strip yield model to the deformation plastic failure assessment diagram (DPFAD), which is dependent on Ramberg-Osgood (R-O) materials to general stress-strain curves. An extension of the DPFAD approach is given which allows the use of material stress-strain data which do not follow the R-O equation such as stainless steel or carbon manganese steel. The validity of the new approach coined piecewise failure assessment diagram (PWFAD) is demonstrated through comparisons with the J-integral responses (expressed in terms of failure assessment diagram curves) for several cracked configurations of non-R-O materials. The examples were taken from both finite element and experimental results. The comparisons with these test cases demonstrate the accuracy of PWFAD. The use of PWFAD requires the availability of deformation plasticity J-integral solutions for several values of the strain-hardening exponent as well as uniaxial tensile stress-strain data at the temperature of interest. Lacking this information, the original R-O DPFAD approach using known engineering yield and ultimate strengths would give the best available approximation. However, it is strongly recommended that actual uniaxial tensile stress-strain data be used when available.

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