材料疲劳循环特性研究

 本文提出用计算分析模拟疲劳实验得到循环应力-应变曲线。列举材料计算的循环应力-应变曲线与实验结果相符合。

STUDIES ON CYCLIC FATIGUE CHARACTERISTICS OF MATERIALS

It is costly and time-consuming to get a material cyclic stress-strain curve by means of fatigue tests. In this paper, the author proposed a computational method which simulates fatigue tests to obtain cyclic stress-strain curve without conducting fatigue tests. After discussing the rel ation between strain hardening laws and the cyclic behaviour of materials, the author derived the incremental elastoplastic constitution equation for a combined hardening model and suggested how to measure the necessary material parameters for the model by simple tests, The finite element analysis results based on this model showed that the model can simulate the Bau-schinger effect during reversed yielding and can correctly account for the effect of strain history on material cyclic characteristics. Some experimental data have been given in this paper. The computed cyclic stress-strain curve is compared with the experimental one and the agreement between them is excellent.