Effect of shot peening on fatigue performance of Ti2AlNb intermetallic alloy

The effect of shot peening on Ti2AlNb fatigue performance was investigated. Glass fine shot peening was used and residual stresses were measured by XRD technology and electropolishing method. Rotating bending fatigue test was performed. The results show compressive residual stress is introduced and the maximum is 322 MPa, and fatigue property is significantly improved. The high cycle fatigue life is prolonged more than 25 times and fatigue endurance limit is increased from 170 MPa to 360 MPa. Moreover, fatigue cracks initiate beneath surface enhanced layer for SP specimens, while for referenced specimens they are located at surface.