SiC/graphene reinforced aluminum metal matrix composites prepared by powder metallurgy: A review

The greater demand for lightweight structural and engine materials for automobile and aerospace applications has compelled the growth of aluminum-based composite materials. These composite materials are likely to be replacements for iron and copper-based composites. This is due to its intrinsic properties such as high specific strength, high specific stiffness, low density, good oxidation resistance, enhanced tribological performance and light weight. In addition to this it can also enhance the fuel efficiency and payload of an engine. Therefore, significant effort has been made to improve the physico-chemical and tribo-mechanical behavior of Aluminum Metal Matrix Composite (AMMCs). Different reinforcements are used with aluminum matrix to enhance its mechanical and tribological properties. However, SiC and Graphene have been the most prominent candidate till date. Hence, this article aims to review the work which has been done to improve the properties of AMMCs by incorporating SiC and Graphene particles. Further, the article also discusses the steps of powder metallurgy to make Al-SiC and Al-Graphene composites. In addition to this, the challenges and their remedies in making Al-SiC or Al-Graphene composite are also addressed. The article also discusses the different strengthening mechanisms provided by SiC and Graphene nanomaterials in AMMCs. The different strengthening mechanism enhances the strength of the composites. In literature, for SiC reinforcement the maximum improvement in thermal conductivity, hardness, ultimate tensile strength and elongation was reported 20 %, 198 %, 295 % and 1.3 % respectively. In addition to this, the maximum percentage reduction in COF and wear rate with addition of SiC was reported 89.28 % and 64.32 % respectively. Similarly, for graphene reinforcement the maximum improvement in thermal conductivity, electrical conductivity, hardness, ultimate tensile strength and elongation was reported 15.40 %, 4 %, 115 %, 81.25 % and 8.15 % respectively. Moreover, the maximum reduction in COF and wear rate with addition of graphene was 12.50 % and 61.74 % respectively.