ABSTRACT Surface treatment is crucial for improving the surface integrity and service life of welded structures. This study explores the effects of cavitation water peening (CWP) on the microhardness, residual stress, tensile, and fatigue properties of 316L stainless steel welded joints and proposes a new engineering prediction model for their fatigue life. Results show that CWP converts surface tensile residual stress to compressive stress, enhancing fatigue strength. A quantitative relationship between microhardness and mechanical properties is found, leading to a model for estimating material properties based on surface hardness. By building a dual‐stage life prediction model and introducing a cyclic stress relaxation equation, an engineering model considering hardness and residual stress evolution is established, significantly improving fatigue life assessment accuracy for CWP welded structures.
Luo et al. (Sun,) studied this question.