Influence of nickel coating of Al2O3(P) reinforced AA-7075 metal matrix composites on hardness, impact strength and tensile properties

Upgrading of hard reinforcements in Aluminum based metal matrix composites (AMMCs) became a key area of research in advanced materials engineering. In this present work, 20 average micrometer-sized alumina particles are coated with nickel using electroless deposition route. The composites are prepared with both coated alumina particles and un-coated particles by reinforcing into AA7075 with 3%, 6% and 9% weight fraction using stir casting technique. Test Specimens were prepared as per ASTM standards. Experiments were conducted and compared with un-coated reinforced composites. Ni-coated reinforced composites were exhibited good results in Hardness and Impact tests when compared with the un-coated composites. Microstructure study was conducted for checking the distribution of reinforced particles. From the experimental investigation, enhancement in hardness, impact energy and tensile strength were identified in the 6 wt% of nickel-coated alumina reinforced 7075 alloy.