Effect of Induction Heat Treatment on the Mechanical Properties of Si3N4-Graphene Al2024 Hybrid Composites

Abstract

Recently, graphene nanoplatelets (GNPs) or silicon nitride (Si3N4) may be employed as a reinforcing element in the Al2024 aluminium alloy matrix due to the solid lubricant property of GNPs and high compressive strength of Si3N4. However, there is no article related to the investigation of the mechanical properties of Al2024-Si3N4-graphene hybrid composites. In this article, Si3N4 or Si3N4/graphene binary particle-reinforced Al2024 aluminium-based composites were produced by powder metallurgy route and induction heat-treatment process. The effects of induction heat treatment (a 500 degrees C sintering temperature and a 35 MPa pressure), Si3N4 (1-12 wt%) and graphene (0.15-0.45 wt%) contents on the microstructure and mechanical strength of Al-based composites were examined. According to the test results, the micro Vickers hardness improved from similar to 94.8 HV (Al2024 alloy) to similar to 105.2 HV (Al2024-9Si(3)N(4)) and similar to 108.5 HV (Al2024-9Si(3)N(4)-0.15GNPs). Similarly, the compressive strength was enhanced from similar to 361 MPa (Al2024 alloy) to similar to 510 MPa (Al2024-9Si(3)N(4)) and similar to 610 MPa (Al2024-9Si(3)N(4)-0.15GNPs). The compressive strength of sintered and induction heat-treated Al2024-9Si(3)N(4)-0.15GNPs composite improved by similar to 8.9% compared with the conventional sintered same specimen's strength. In conclusion, the induction heat-treatment process and Si3N4/graphene addition significantly enhanced the mechanical strength of Al2024 hybrid composites.