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New Stress-Strain Model for Identifying Plastic Deformation Behavior of Sheet Materials

판재의 소성변형 거동을 동정하기 위한 새로운 응력-변형률 모델

  • Kim, Young Suk (School of Mechanical Engineering, Kyungpook National University) ;
  • Pham, Quoc Tuan (Department of Mechanical Engineering, Graduate School, Kyungpook National University) ;
  • Kim, Chan Il (Institute of Mechanical Engineering Technology, Kyungpook National University)
  • Received : 2016.10.06
  • Accepted : 2017.01.06
  • Published : 2017.04.01

Abstract

In sheet metal forming numerical analysis, the strain hardening equation has a significant effect on calculation results, especially in the field of spring-back. This study introduces the Kim-Tuan strain hardening model. This model represents sheet material behavior over the entire strain hardening range. The proposed model is compared to other well known strain hardening models using a series of uniaxial tensile tests. These tests are performed to determine the stress-strain relationship for Al6016-T4, DP980, and CP Ti sheets. In addition, the Kim-Tuan model is used to integrate the CP Ti sheet strain hardening equation in ABAQUS analysis to predict spring-back amount in a bending test. These tests highlight the improved accuracy of the proposed equation in the numerical field. Bending tests to evaluate prediction accuracy are also performed and compared with numerical analysis results.

Keywords

References

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