Tribological and friction-induced vibration and noise performance of Ti6Al4V-multilayer graphene self-lubricating composites

Abstract

Experimental studies of tribological and friction-induced vibration and noise properties of Ti6Al4V alloy (TC4) and Ti6Al4V-1.5 wt% multilayer graphene (MLG) self-lubricating composites (TMC) are comparatively performed using a new-developed friction noise experimental apparatus. The results show that the friction-induced vibration and noise are closely related to the interface wear behavior. As for TC4, due to its relatively small hardness, the interface is severely worn with some uneven factors (e.g. plowing action, adhesion tearing and asperities deformation) during the tests, leading to the strong fluctuation of friction force that make the friction coefficient increase and quickly reach to the threshold value until the occurrence of unstable vibration and squeal noise. In contrast, the interface of TMC is worn slightly because an anti-friction film rich in MLG is well formed on the wear scar, which causes the friction force to change gently. Hence, the friction coefficient remains in a minor state with a relatively small fluctuation, and finally the intensity of vibration and squeal noise decreases. This investigation was meaningful to improve the properties of anti-friction and wear resistance, as well as vibration and noise reduction of Ti6Al4V alloy.