Tribological behaviour of multi-walled carbon nanotubes reinforced AA 7075 nano-composites

Abstract

Carbon nanotubes (CNTs) play a major role in the development of new materials for high temperature, high strength, and better wear properties. In this paper, multi-walled carbon nanotubes (MWNTs) were reinforced with AA7075composites through a powder metallurgy route. The powders were consolidated using a uniaxial press at 400 MPa and followed by sintering at 5800°C in an argon atmosphere. The composites were characterised by XRD and FESEM, and microhardness of the compound was calculated by Vickers hardness tester. Wear and friction experiments were performed using a pin on a friction style disc and a data gathering equipment in accordance with ASTM G99 standard. The effect of sliding interface temperature on friction and wear behaviour was reported. The wear rate and friction coefficient of composites worsen with increasing carbon nanotube concentration. In comparison to the AA7075 matrix without reinforcement, AA7075/MWNTs composites have a moderate wear rate and a lower coefficient of friction; the optimal MWNTs content is 1 wt%. Wear properties of AA7075/MWNTs composites were improved compared to AA7075 alloy at Room temperature, 1000°C, and 2000°C temperatures.