Effect of surface treatments on fretting fatigue of Ti-6Al-4V

The objective of this work was to investigate the performance of several coatings and surface treatments subjected to fretting fatigue with Ti-6Al-4V specimens and pads. Five coating systems were initially chosen and tested using two different fretting fatigue apparatus. The five coating systems considered were two types of Diamond Like Carbon (DLC), plasma sprayed molybdenum coating, electroless nickel-boron, and a plasma nitrided surface. In addition to the coatings, two surface treatments, Laser Shock Processing (LSP) and Low Plasticity Burnishing (LPB) were also considered both with and without coatings. Specimens with two of the best performing coatings were first subjected to LSP and LPB prior to coating application and then tested for fretting fatigue. These initial results show that the DLC coating significantly improves the fretting fatigue lives of the laboratory specimens.