核设备筒体零件局部变形后的材料性能变化和残余应力研究

The Study of Material Performance and Residual Stress Changes on RVI Core Barrel after Local Deformation

压水堆核电站某设备的主体材料是奥氏体不锈钢,筒体是该设备的重要组成部分,对尺寸精度要求苛刻。筒体焊接后往往需要局部校圆,然后进行尺寸稳定化热处理。校圆过程中如操作不当可能会产生局部变形,变形处材料性能及应力状态也会随之发生变化。本文通过模拟局部变形进行材料性能试验,采用X射线衍射法测量不同阶段筒体表面的应力,以探索筒体局部变形、尺寸稳定化热处理影响材料性能和表面应力的规律。

Austenitic stainless steel is the main material of the RVI in light water reactors.As an important part of RVI,core barrel has stringent requirement of dimensional accuracy.After welding,the local core barrel is usually required to be circle checked.In that processing,improper operation may cause local deformation,which can change the properties of the materials,the residual stress distribution will also be changed.This paper researched regulation of local deformation,dimensional stability heat treatment affecting on material performance and residual stress,by material mechanics experiment on simulator of local deformation,and stress measurement on the surface of core barrel in different stages.