Comparison Research on Mechanical Properties of High Temperature Alloy after Laser Peened and Ultrasonically Peened

Abstract

For comparative study of the influence of laser shock peening and ultrasonic shot peening on the mechanical property of superalloy K403, untreated, ultrasonic shot peening with 850°C heat preservation, laser shock (heat preservation, Hp), the fatigue testing of samples under four states were conducted at room temperature, and the analysis of two techniques’ influence on the mechanical properties of K403 was done by hardness tester, profile tester, scanning electron microscopy (SEM). The results indicated that LSP with Hp, LSP, USP with Hp can improve the fatigue life of K403 respectively for 2.4, 2.25, 1.4 times more longer than untreated sample; the increase of micro-hardness gradient after LSP were smaller than after USP. The SEM studies showed that the γ' phase distortion was elongated and the plastic deformation of samples by LSP was larger than by USP.