Influence of Severe Double-Shot Peening and Plasma Spray Arc TiAlCr /AlCrSi Coating on Tribological Behaviour of Pure Aluminium Alloy

In this research work, the severe double-shot peening (SDSP) and TiAlCr /AlCrSi plasma spray coating were performed on the commercial structural fabrication materials (Aluminium alloy) to improve the microstructure and surface properties. The materials were adapted to the shot peening process; compressive residual stress and microstrain were formed in the outer surface region as a grain size measurement of 25 µm. The oxygen reduction for Plasma spray TiAlCr/AlCrSi coating was implemented at the base materials; Al–Ti eutectic solid phase was directly converted into twin boundaries and Al lattice structure. Oxidation of micrographs revealed the fine grains boundaries, α′delta phase, porous titania (TiO2) surface, and lower surface roughness. Further, a higher hardness value for the oxidation sample was seen compared to base materials which were 36% augmented. Tensile results of SDSP and TiAlCr/AlCrSi coating were observed as the ultimate strength of 389 MPa and 420 MPa, 437 MPa. AlO2 surface and multiple bonding structures mainly contributed to the tensile strength of samples. Potential dynamic polarization studies were conducted on the three samples using 3.5% NaCl solution under natural environmental conditions to increase the corrosion resistance of the base materials. CrN and Cr2N did not observe on the outer surface. Further, dimples, voids, and cracks were not formed in the inner and outer surface layers. The plasma spray TiAlCr/AlCrSi coating method showed better results compared to shot peening process samples and increased the high tensile strength and elongation ratio of the fracture faces.