Effect of Nickel Reinforcement on Micro Hardness and Wear Resistance of Aluminium Alloy Al7075

Abstract

Presently, wear resistance of aluminium alloys have gained a greater importance in various industrial applications. Research works regarding strengthening of aluminium alloys introduced a new class of composites, i.e. aluminium intermetallic composites. Aluminium alloy Al7075 with zinc as the major alloying element is widely used in various industrial fields, and there is a research scope in fabricating Al7075-Al3Ni intermetallic composites by reinforcing nickel particles. In this study, four composites of different weight percentages (i.e. 1%, 5%, 10%, and 15%) of nickel and base alloy were fabricated by using stir casting method. After fabrication, the materials were subjected to T6 heat treatment. The micro hardness evaluation of the composites before and after the heat treatment was performed, and compared with the base alloy. Micro hardness of base alloy was improved up to 146% by reinforcing 15% nickel followed by the heat treatment. Wear rate of heat treated base alloy and composites was studied. Heat treated Al7075+15% nickel composite shows more wear resistance (about 93% resistant than heat treated base alloy). The wear properties of heat treated Al7075+15% nickel composite was studied at different applied loads and sliding velocities.