Investigations of the Tribological Properties of Marine-Derived Biowaste Based Reinforcements of Aluminum Composite Prepared By Ultrasonic Assisted Stir Casting Process

Abstract

Developing high-performance, lightweight Aluminium based composites is essential for cutting-edge structural applications, especially in the aerospace and automotive industries. The AA7075-based composites are produced with reinforcement particles of Yttrium Oxide (Y₂O₃) and seashell powder individually and combined with stir casting and an ultrasonic-assisted stir casting method. Fabricated base cast alloy and composites microstructural, microhardness and wear studies were investigated by optical & scanning electron microscopy, microhardness tester and pin-on-disc tribometer respectively. The dry sliding wear behaviour of samples were studied under ambient circumstances, with varied loads of 20N, 30N, and 40N, at a 1 m/s constant velocity and of 1500m sliding distance. The load and sliding velocity significantly impact the wear properties of composites. Results shows that the ultrasonic assisted stir cast samples have more homogeneous dispersion of particles in the Al alloy and reduce particle agglomeration in compare with stir cast samples. The hybrid cast samples AA7075 + Y₂O₃ + Seashell composites have the better hardness and wear resistance in compare with base cast alloy in both fabricated conditions.