Life cycle strengthening of high-strength steels by nanosecond laser shock

Laser shock peening is a surface treatment technology inducing high-pressure shock waves on metallic materials and structures. In this study, the life cycle performance improvement in high-strength steel by nanosecond laser shock peening is investigated. It is found that microstructures formed by laser shock peening lead to higher microhardness, corrosion resistance, and fatigue life, which are significantly beneficial for preventing life cycle failure of mega-scale engineering structures in critical environments. The residual stress is also measured on the surface of samples, which shows that the compressive residual stress can be found in the treated area.