Production of Al-5Cu Alloy Composites Reinforced with Few-Layered Graphene by Powder Metallurgy Method

Abstract

Aluminum based alloys have been widely used in the automotive, aircraft and defense applications because of good thermal and electrical conductivity, high tensile strength-to-weight ratio, high hardness, and ductility properties. Graphene, is an allotrope of carbon, attracts great attention worldwide due to its sp 2 -hybridized two-dimensional honeycomb structure, low weight, thermal, electrical, and mechanical properties. In the present study, high purity few-layered graphene (FLG) which was synthesized via electric arc discharge method (EAD) were reinforced to the Al-5Cu alloy matrix using various weight fraction of 0, 0.1, 0.3, and 0.5, by mechanically alloying (MA). These nano-composite powders were consolidated by cold pressing under 450 MPa and they were subjected to sintering at 570 °C and 580 °C for 3 hours under argon atmosphere. The microstructure of composites materials was studied by optical microscope and scanning electron microscopy. The FLG was observed to be dispersed homogeneously in the Al-5Cu alloy matrix. An increase in the micro hardness for Al-5Cu alloy with 0.5 wt% FLG (123 HV) by 45% was observed compared to pure Al-5Cu alloy (85 HV) sintered at 570 °C. Moreover, wear properties of these composite materials were investigated by means and analysis of variance (ANOVA).