Elevated temperature fretting fatigue of Ti-17 with surface treatments

Fretting fatigue of Ti-17/Ti-8-1-1 contacts at 316 °C is examined experimentally. Different surface treatments are analyzed, including coatings, lubrication, and levels of shot peening. The evolution of friction is examined for a range of surface treatment. Fretting fatigue life for baseline specimens are obtained for a range of load parameters to determine loads that yield fretting fatigue lives of approximately 100,000 cycles. This applied load level was maintained constant for the different combinations of surface treatments to investigate the influence of surface treatment on fretting fatigue life. The Cu–Ni–In and Al–Br coatings and MoS2 and Everlube lubricants are removed early in the fretting fatigue experiment; hence these surface treatments had little effect on fretting fatigue life. Shot peening increases fretting fatigue lives by about 60%. Block loading experiments show that minor cycles reduce fretting fatigue life.