厚壁管自增强残余应力计算模型

基于对材料应变硬化行为的不同简化得到不同的自增强理论模型 ,如理想弹塑性模型、线性应变硬化模型、幂硬化模型以及这些简化的应变硬化模型的组合模型等。不同的模型适用于不同的应变硬化行为的材料。本文提出了一种无需对材料的应力应变行为进行简化 ,考虑材料应变硬化行为和包辛格效应的厚壁管自增强理论一般模型。由于包辛格效应系数是预应变的函数 ,本模型用参数来考虑这种影响。该模型模型中用到的计算参数通过对材料拉压曲线的拟合得到 ,理想弹塑性模型 ,线性强化模型以及幂硬化模型等都是本模型的特例。

An Autofrettage Residual Stress Calculation Model of Thick-walled Cylinder

There are some different autofrettage models based on different simplified material strain-hardening behaviors,such as linear strain-hardening model, power strain-hardening model, and the combination of these strain-hardening relationship models. Each of them suits for different strain-hardening materials. In this paper, a general autofrettage model considering the material strain-hardening relationship and the Bauschinger effect, based on the actual tensile-compressive stress-strain curve of material and modified yield criterion, has been proposed. Because of the coefficient of Bauschinger effect is the function of the prestrain, it can be considered by parameter. These parameters needed in present model are determined by fitting the actual tensile-compressive stress-strain curve of the material. Each of those models mentioned above is a special case of this general model.