Influence of micro-sized Al2O3 particles on mechanical and wear performance of an AA7075-Al2O3 composite coating developed by friction surfacing

In the present study, a wear-resistant AA7075-Al 2 O 3 composite coating was efficiently developed on an AA6082 substrate via the friction surfacing technique. Micro-sized Al 2 O 3 particles were used as reinforcement material by filling in the blind holes drilled on the face of the consumable rod (AA7075) to develop the composite coating. The consumable rod rotational speed (1000–1400 rpm), number of blind holes (1–3) and travel speed (140–180 mm/min) were considered as input parameters. The composite coating’s dry sliding wear, microhardness and bond strength were chosen as output response characteristics. Grey relational analysis was utilized to multi-objectively optimize the input parameters while the experiments were carried out in accordance with the Taguchi L9 orthogonal array. The multi-objective optimized input parameters were found to be the rod rotational speed of 1200 rpm, a travel speed of 140 mm/min, and three holes, respectively. Under optimal conditions, the bond strength of the AA7075-SiC composite coating is 170.4 MPa, and its wear (weight loss) is 56.02% and 41.6% less than that of AA7075 and AA6082, respectively. The microhardness of the composite coating developed at optimal parametric setting (174.2 HV0.1) was 99.98% and 11.31% higher than that of the substrate (AA6082) material (87.11 HV0.1) and rod (AA7075) material (156.5 HV0.1) respectively.