An approach for obtaining surface residual stress based on indentation test and strain measurement

Abstract

Abstract During the welding process of welded joints in nuclear power plants, uneven deformation caused by temperature changes will lead to the generation of residual stress. Aiming at the problem that the demarcate experiment is easy to cause errors when the traditional indentation strain method is used to measure the residual stress. Using 316L austenitic stainless steel as an example, ABAQUS finite element simulation is combined with physical experiments to study the effects of different indentation depths on the strain increment after unloading under a state of residual stress. The results show that the indentation depth and strain increment are linearly related. Based on the linear relationship, an independent parameter that characterizes the residual stress is obtained and a model between the parameter and residual stress established. It provides a certain basis for the convenience and precise detection of residual stress in nuclear power plants machinery structures in service.