Abstract
Elastic-plastic and isotropic hardening material model have been often used for cold forging simulation. However, such material model is not possible to represent Bauschinger effect. On the other hand, it is important to consider Bauschinger effect for the evaluation of the strength of forged part without heat treatment, one of which is a cold forged bolt by stainless steel. In this present paper, for different multi-stage cold forging process of non-heat treated bolts, the forging process and strength evaluation applying the combined hardening model possible Bauschinger effect is simulated. As a result, the effect of Bauschinger effect on the forging process can be expressed by the combined hardening model. Moreover, the difference between isotropic and combined hardening models on the estimated strength of the forged part can be elucidated clearly.
