Effect of Milling on the Hardness and Wear Behaviour of Cast Al6061 Reinforced with Al2O3 Nanoparticles

Abstract

Alumina nanoparticles is generated through planetary ball milling of powder mix compraise of aluminium (Al) and manganese dioxide (MnO<inf>2</inf>). The powder mix of Al and MnO<inf>2</inf> is considered in the weight proportion of 1:2.416 and milled for 120, 240 and 360 min. In the milling jar, the powder mix will experience impact force while collusion with ball-powder-ball and ball-powder-wall of the jar. These impact force will cause cyclic deformation and fracture of the powder mix, which results in the synthesis of nano alumina. The morphology of the powder mix prior to milling and post milling for different times has been studied by scanning electron microscope and X-ray diffraction. Cast composites have been synthesized via liquid metallurgy technique using Al6061 as matrix and generated alumina particles by milling is considered as reinforcement. Comparative study have been conducted between the composites prepared by considering Al6061 as matrix and as received powder as reinforcement with the composites prepared by considering Al6061 as matrix and alumina generated through the milling as reinforcement. The reinforcement added to the the matrix in the varying proportions of 0.5, 1 and 1.5 wt% of particles before milling and after milling. The effect particles size related to hardness and wear property of cast composites are studied. It was found that the wear resistance increased monotonically with hardness. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG.