Effect of MWCNTs and heat treatment on coefficient of friction and wear characteristics of MWCNTs reinforced Al6082 composites under dry sliding condition

Abstract

Herein, MWCNTs/Al6082 composites were produced using a stir casting technique, and their tribological behavior was studied in as-cast and T6 heat-treated conditions using a pin-on-disk tribometer at a sliding speed of 2 m/s (fixed) and varying applied load (40, 60, and 80 N) and sliding distance (500–3000 m). Morphology of composites and worn-out surfaces were studied using a scanning electron microscope (SEM). Linear increment in wear rate was observed with sliding distance up to transition limit and then upsurged drastically beyond that limit. At 40 N, a protective layer started forming between the disk and surface of pin, which reduced coefficient of friction (COF), and wear mechanism was abrasion and oxide. Annihilation of protective layer at higher load increased COF and observed wear mechanism was adhesion and delamination. Wear resistance of alloy and nanocomposites was enhanced by heat treatment due to the strengthening of matrix. Wear rate of Al matrix was reduced with MWCNTs due to their self-lubricating property.