Improving the wear resistance of Ti–6Al–4V alloy through electro-pulsing combined with laser shock peening

Abstract

In this study, the effects of surface treatment namely electro-pulsing followed by laser shock peening (EP-LSP) on wear resistance properties of Ti–6Al–4V alloy are investigated. It was compared with samples treated solely with laser shock peening (LSP) and electro-pulsing treatment (EP) to investigate the effects of different processes on the friction and wear properties of Ti–6Al–4V alloy. In addition, the friction coefficient, wear rate, wear morphology were also investigated. Finally, the wear mechanism was described in detail. The results demonstrated a significant reduction in grain size for the samples after EP-1-LSP treatments. Furthermore, compared with the as-received samples, the maximum hardness of EP-1, LSP and EP-1-LSP treated samples increased by 6.5%, 5.9%, and 19.6%, respectively, and the compressive residual stress on the surface increased by 2.4%, 15.0%, and 37.2%, respectively. Under the same friction conditions, the depth of wear scar of the samples after EP-1, LSP, and EP-1-LSP treatments decreased by 7.2%, 10.6%, and 18.5% than that of the as-received sample. The as-received samples mainly exhibited severe oxidative and adhesive wear, and the LSP and EP-1 treated samples showed slight adhesive and oxidative wear. The EP-1-LSP treated samples predominantly showed signs of abrasive wear.

Keywords

• Electro-pulsing
• Laser shock peening
• Friction and wear behavior
• Microstructure characteristics
• Wear mechanisms