A Study on Hardness and Effective Strain of Cold-Worken Products

냉간 가공 제품의 경도와 유효 변형률에 관한 연구

  • 최영 (인제대학교 수송기계부품기술혁신센터) ;
  • 박준홍 (부산대학교 기계기술연구소)
  • Published : 2004.09.01

Abstract

It is already known that hardness number of cold-forged product is in close conjunction with its effective strain. This paper presents the method to predict the relation between effective strains and hardness by using FE-simulation of hardness test from the conception that hardness indicates resistance to plastic deformation. The results of FE-simulation for the materials are compared with those of experiments and also compared with those of experiments in reference to show the feasibility of the proposed method. In addition, the present method was applied to the cold-forged product to verify the relation between hardness and effective strain. As a result, the predicted hardness number by the present method is in good agreement with experimental values. Prediction of hardness fur a cold-forged product comes to be possible by estimating the relation between effective strain and hardness using the proposed method in this study.

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