Effect of Silicon Carbide and Boron Carbide on Mechanical and Tribological Properties of Aluminium 7075 Composites for Automobile Applications

In the current study, aluminium 7075 were reinforced with different wt% (2 to 6) of silicon carbide (SiC) and aluminium 7075 hybrid composites reinforced with different wt% (2 to 6) of silicon carbide (SiC) with constant 2 wt% of boron carbide (B4C) were fabricated using the Powder Metallurgy method. The microstructural study of sintered samples was performed using FESEM. This mechanical alloying process helped uniform distribution of SiC and B4C particles throughout the aluminium matrix. Electron backscatter diffraction studies demonstrated that Al7075 + 6wt%SiC particles have a finer grain structure. Aluminium 7075 alloy composites analysed using XRD to confirm the peak phases. The higher hardness values were obtained for Al7075 + 6wt% SiC and Al7075 + 3wt%SiC + 2wt%B4C composites as 195 HV and 161 HV respectively. The higher compressive strength values were obtained for Al7075 + 3wt%SiC and Al7075 + 2wt%SiC + 2wt%B4C composites as 220 MPa and 175 MPa respectively. The density of hybrid composites had a considerable impact on the influence of SiC and B4C particles. The surface nature of Al7075 + 2wt%SiC and Al7075 + 4wt%SiC + 2wt%SiC composites have obtained as hydrophilic and hydrophobic respectively. Based on the thermal conductivity measurement, it was found that the Al7075 + 6wt%SiC composite sample has obtained the thermal conductivity of 58.99 W/m.K. Furthermore, the investigation on wear studies showed the wear rate for Al7075 + 4wt%SiC and Al7075 + 6wt%SiC + 2wt%B4C composite as smaller under the load of 10N. The Al7075 + 6wt%SiC and Al7075 + 2wt%SiC + 2wt%B4C hybrid composites have a higher corrosion resistance than in a 3.5% than the other aluminium 7075 composite samples.