Improvement of Fatigue Performance for Commercial Pure Titanium by Combined High-Energy Shot Peening

In order to improve the fatigue performance of pure Ti,firstly,nano-crystallization in surface layer of pure titanium was carried out by high-energy shot peening with shots in big diameter,and then the shot peening with shots in small diameter was introduced to degrade the surface damage.Took determination to the surface quality of combined shot peening,fatigue strength and fatigue fracture morphology.Then compared the results to the high-energy shot peening with pure and unpeened sample.The results show that the combined high-energy shot peening on surface layer of pure titanium could effectively ameliorate the surface damage and high roughness which were caused by high-energy shot peening,thus the fatigue strength of pure titanium significantly.Comparing with the unpeened samples the fatigue strength of the samples by combined high-energy shot peening increased by 52.3% and comparing with the high-energy shot peening the fatigue strength was relatively increased by 13.6%.