Studies on Adhesive Wear Characteristics of Heat Treated Aluminium LM25/AlB2 Composites

The main aim of this study was to determine the adhesive wear characteristics of heat treated LM 25/AlB2 metal matrix composites fabricated using liquid metallurgy route. The composite samples were solutionized at 525 °C and then water quenched. Aging was done at different temperatures (160 °C, 175 °C, 200 °C and 250 °C) for different aging time (4 hrs, 6 hrs, and 8 hrs). Brinell hardness tester was used to evaluate the hardness of all aged samples and maximum hardness (82 HRB) was observed in the sample aged for 6 hours at 250°C . Those heat treated specimens were taken for further experimentation on wear characteristics. Pin-on-disc tribometer was used to analyse the dry sliding wear characteristics and the experiments were conducted based on Taguchi’s L16 orthogonal array by varying the process parameters of load (10 N, 20 N, 30 N and 40 N), sliding distance (400 m, 800 m, 1200 m and 1600 m) and sliding velocity (1 m/s, 2 m/s, 3 m/s and 4 m/s) for four levels. The dependence of wear rate on various parameters was found out using ANOVA and S/N ratio. The experimental result shows that sliding velocity (56.6 %) influences more on wear rate followed by load (23.09 %) and sliding distance (6.02 %). The regression equation was developed and the confirmatory result shows less error. The worn surfaces were analysed using Scanning Electron Microscope and severe delamination at the sliding velocity of 1m/s was found.