引入内结构张量的非比例循环塑性本构模型

考虑非比例加载情况下金属材料塑性循环强化特性的本构描述,为反映由于非比例加载而引起材料的附加等向强化及异向强化效应,提出在Valanis的塑性内时响应方程中引入与加载路径几何性质有关的内结构张量,建立了新的非比例循环塑性本构模型.其中,材料强化程度采用沿路径法线方向的塑性应变分量描述.用所建模型对304不锈钢材料在一些典型非比例循环加载路径下的响应进行了理论预测,并与相关文献中的实验结果进行了比较,结果令人满意.

A Non-proportional Cyclic Plasticity Model Taking into Account Internal Structural Tensor

This paper is concerned with the formulation of a new cyclic plastic constitutive model to describe the hardening behavior of metallic materials under non-proportional cyclic loadings.In order to describe the additional isotropic hardening and the anisotropic hardening due to non-proportional loading,an internal structural tensor related to the geometry of loading path is incorporated into Valanis' endochronic constitutive equations.The plastic strain component along the normal of loading path is presented to measure the hardening.The proposed model was applied to simulate the stress responses of 304 stainless steels for a variety of typical non-proportional cyclic loading paths.The predictions have a good agreement with the experimental results in the references.