Microstructural, mechanical and wear characteristics of AA7075/TaC/Si3N4/Ti based hybrid metal matrix composite material

Abstract

Abstract The current investigation was structured at estimating the corrosion, microstructural, wear and mechanical interpretation of hybrid metal matrix composites (HMMCs) depending upon aluminium alloy (AA) 7075 assisted with Tantalum Carbide (TaC), Silicon Nitride (Si3N4) and Titanium (Ti). For this purpose, five disparate composites with distinctive wt% of reinforcements were created by traditional stir casting mechanism. Scattering of the reinforced particles were analysed with computerized Scanning Electron Microscope (SEM), X-ray Diffraction (XRD) and Optical Microscope (OM). Mechanical characteristics like compression strength, density and porosity were inspected on the developed HMMCs at ambient atmosphere. Wear performance was inspected by utilizing a pin-on-disc device to substantiate the enrichment of the wear resilience both at ambient and high temperatures, in terms of coefficient of friction (COF) & wear rate (WR). Microstructural analyses reveal the presence of TaC, Si3N4 & Ti with uniform dispersion and considerable interfacial fusion between the matrix and ceramic particles. The outcomes revealed that, combination of TaC/Si3N4/Ti reinforcements with AA7075 automatically enhanced the mechanical properties. Theoretical and experimental densities were found to be 3.11 g/cm3 & 3.09 g/cm3 when compared to the density of base alloy. However, the highest compression strength was 634 MPa at 1 wt% of TaC and 8 wt% of Si3N4 and 2 wt% of Ti in hybrid composite. The results portrayed that the WR and COF of the developed HMMC are lesser than that of the pure AA7075 alloy and later diminishes with rising TaC/Si3N4/Ti content.