Effect of graphene content and induction hot pressing on tribological and mechanical behavior of Al6061-based composites

This work intends to fabricate Al6061 alloy and Al6061-graphene composites via powder metallurgy and induction hot pressing techniques. This study also investigates the effect of graphene content (0.15, 0.30, and 0.45 wt.%), heat-treatment process (sintering, hot-pressing process), and applied load (5 and 10 N) on the compressive strength, hardness, density, mass loss, friction coefficient, wear rate, and microstructure. Tribological test results showed that minimum mass loss (0.0011 g), wear rate (8.5 x 10-8 mm3/(Nm)), and friction coefficient (0.23) were obtained at sintered and hot-pressed Al6061-0.15 wt.%graphene composite for a 5 N load. Hardness and compressive strength increased from 95 HV, 253 MPa (Al6061 alloy) to 151 HV, 395 MPa (Al6061-0.15 wt.%graphene) with sintering and induction hot pressing process, respectively. Compared to Al6061 alloy, the wear rate and compressive strength of Al6061-0.15 wt.%graphene improved by 30% and 33% for sintered and hot-pressed specimens, respectively. It has been determined that the tribological and mechanical properties of sintered and hot-pressed specimens are similar to 15% better than those of only sintered samples. As a result of the paper, it was concluded that the addition of uniformly dispersed graphene and the induction hot-pressing process enhanced the mechanical and tribological behavior of aluminum-based composites.