Effect of shot peening on fatigue crack propagation of Ti6Al4V

Abstract

In order to study the influence of shot peening on the fatigue crack propagation characteristics of Ti6Al4V (TC4) titanium alloy, under the condition of cyclic load amplitude 12 kN, stress ratio 0.1 and loading frequency 5 Hz, the uniaxial tensile fatigue tests were carried out on the original and shot peening specimens respectively, and the crack length and small crack propagation rate were calculated under different stress cycles. The results showed that the short crack propagation rate of shot peening TC4 titanium alloy decreased by 34 % ∼ 60 %, but the long crack propagation rate tended to increase. The overall performance was that the occurrence time of visible crack was delayed by 64.3 %, and the fatigue life was increased by 34.2 %, which showed that shot peening could effectively improve the fatigue performance of TC4 titanium alloy. This study can provide a theoretical reference for improving the fatigue performance of aviation materials and has a good engineering application value.