Influence of Shot Peening on the Isothermal Fatigue Behavior of the Gamma Titanium Aluminide Ti-48Al-2Cr-2Nb at 750 °C

One possibility to improve the fatigue life and strength of metallic materials is shot peening. However, at elevated temperatures, induced residual stresses may relax. To investigate influence peening on high-temperature behavior, isothermal tests were conducted shot-peened untreated samples gamma TiAl 48-2-2 750 °C in air. The material was characterized using EBSD, microhardness, stress analyses. Shot leads a significant increase surface hardness high compressive near surface. Both effects have positive lifetime. it also notches tensile bulk with negative impact cyclic During fully reversed uniaxial tension-compression (R = ?1) amplitude 260 MPa, dominate, lifetime increases. At lower 230 effect internal dominates, decreases. transition from volume crack initiation if not damaged by shots.