1Cr18Ni9Ti不锈钢单轴棘轮本构模型研究

Study on Uniaxial Ratcheting Modeling of1Cr18Ni9Ti Stainless Steel

对 1Cr18Ni9Ti不锈钢进行了室温单轴棘轮试验 ,研究了平均应力、峰值应力和棘轮历史对饱和棘轮应变的影响规律。结果表明 ,当平均应力大于一定范围后 ,饱和棘轮应变与峰值真应力之间存在单调函数关系 ,先前低峰值应力的棘轮历史 ,对后继高峰值应力的饱和棘轮行为无影响。给出了用于室温饱和棘轮应变预测的模型和用于棘轮应变演化预测的模型。

Series of uniaxial ratcheting experiments of 1Cr18Ni9Ti stainless steel were carried out at room temperature. The influence of mean stress, maximum stress and the histories of ratcheting on the saturated ratcheting (SR) strain were investigated. The results show that the SR strain varies monotonously with the maximum true stress when the mean stress exceeds a certain value; the preceding ratcheting histories with lower maximum stress have no influence on the following SR strain with higher maximum stress. A model simulating the evolution of ratcheting strain at room temperature is presented, as well as a model for predicting the SR strain. Comparing with the experimental results, the prediction of the developed models is proved to be well.