Chapter 63 Repair of Shot Peening on Fatigue Properties of High-Strength TC18 Titanium Alloy for Aviation

摘要

In this paper, the machining texture and shot peening (SP) on the fatigue properties of a high-strength TC18 titanium alloy for aviation were studied. The surface texture, surface morphology, hardness distribution, and residual stress characteristics of fatigue specimens were analyzed by using scanning electron microscopy (SEM), micro-hardness tester, and X-ray diffraction residual stress analyzer. The results showed that the fatigue life of the axial texture processing was 27 % lower than that of the axial polishing specimens (BM). But circumferential texture processing was 72 % lower than that of BM. It was attributed that the fatigue cracks was initiation easily by circumferential texture processing. Then, SP technology was induced to repair the fatigue life of the circumferential texture processing specimens. Compared with the BM specimens, the fatigue life of SP specimens increased approximately 12 times. That was attributed to the depth of compressive residual stress field induced by SP.