基于应变硬化模型的复合自增强圆筒的应力分析

自增强是通过提高压力容器的残余应力来增强他们的承载能力和疲劳寿命。自增强复合圆筒可以承受比一个具有相同尺寸的单层圆筒更高的压力。引入了应变硬化模型,对自增强复合圆筒的残余应力进行了分析,并对其分布进行了预测。研究表明:复合圆筒内壁的切向残余应力和应力幅随着超应变度的增大而增大。缩套是提高压缩残余应力的一个非常有效的方法。

Stress Analysis of an Autofrettaged Compound Cylinder Based on Strain Hardening Models

The autofrettage process is used to enhance the carrying capacity and fatigue lifetime of pressure vessels by introducing compressive residual stress into them. An autofrettaged compound cylinder can resist a higher pressure than a single cylinder having the same dimension. Strain hardening models were investigated, residual stress analysis of an autofrettaged compound cylinder was conducted. The residual stress distribution of the autofrettaged compound cylinder was predicted. The results show that：the tangential residual stress and stress amplitude of an autofrettaged compound cylinder increased with the overstrain level. The shrink fit process is a very efficient way to extend compressive residual stress.