Abstract: An integrated ultrasonic deep rolling and burnishing technology for anti-fatigue manufacturing is used for surface enhancement treatment of titanium alloy fatigue specimens. Rotating bending fatigue tests are performed for treated and untreated fatigue specimens. The fatigue fracture of cracked specimens is observed and investigated via scanning electronic microscopy. Results show that ultrasonic deep rolling treatment leads to substantial increase in fatigue strength of the titanium alloy specimens. A thin layer of fine microstructure is developed on the surface of the treated specimen which serves for inhibition of fatigue crack initiation and propagation. Comparisons of the fatigue striations indicate that the ultrasonic deep rolling treated specimens show obvious finer fatigue striation than those of the untreated specimen.

Key words: Fatigue striation, Mechanical surface enhancement, Ultrasonic deep rolling