Dry Sliding Wear Behaviour of T6-Aluminium Alloy Composites Compared with Existing Aircraft Brake Pads

Current research investigates the effect of casehardening, plasma nitriding and T6 heat treatment condition on the dry sliding behaviour of microwave-assisted T6-AA2900-α-Al2O3composite material against aircraft disc material. Composite samples without post-treatment were also considered for the evaluation. Experiments were carried out with a pin-on-disc wear tester at maximum brake operation temperature of 450 °C. The results show that formation of Al4C3 and AlN on the surface and near subsurface influences the coefficient of friction and the specific wear rate regimes close to aircraft brake operating parameters. The developed composite material featuring homogeneously dispersed α-Al2O3, homogeneously nucleated Al4C3exhibits a better behaviour, as compared to surface formed AlN. The results were obtained comparing explicit characteristics (i.e. braking COF-wear and temperature effects) of the surface modification on T6-composite under the aircraft braking conditions. Counter disc characterisation was also carried out to understand the impact of the surface modification, temperature effects and microwave T6 condition.