Numerical simulation of Laser peening by macro impact And the peening effect on fatigue life, and weld residual stresses

摘要

Tension weld residual stress (WRS) is detrimental for stress corrosion cracking of In600 and high cycle thermal fatigue of austenitic steels. Laser-peening (LP) is a surface mitigation technique for improving the life of metallic components through the generation of a compressive residual stress (RS). Impact of WRS and strain hardening (SH) are considered. SH has a detrimental effect [1] on fatigue life under cyclic strain control for alloys with a memory effect (In600-304-316) because SH modifies the cyclic strain stress loop. LP simulations are performed by 3D FEM using a high-speed explicit dynamic code, using the Johnson-Cook's law which is identified at strain rate of 10~6.