Tribological behavior of aluminum nanocomposites studied by application of response surface methodology

An aluminum Al-0.8Al(2)O(3) and Al-1.6Al(2)O(3) nanocomposite was prepared by a novel ultrasonic assisted stir casting method. A three-level Box-Behnken design of experiment was developed using response surface methodology. Dry sliding wear tests were performed as per the experimental design using a pin-on disc setup at room temperature. Analysis of variance (ANOVA) was applied to investigate the influence of process parameters, viz., wt.% reinforcement, load and sliding distance, and their interactions on specific wear rate and coefficient of friction. Further, a mathematical model has been formulated by applying response surface method in order to estimate the tribology characteristics such as wear and COF of the nanocomposites. The specific wear rate and coefficient of friction are significantly influenced by % of Al2O3 and load. The wear test parameters were optimized for minimizing specific wear rate and COF using desirability function approach. A set of optimum parameters of combination for AMMNC was identified as Al2O3-1.1 wt.%; load, 34 N and sliding distance, 2931 m with specific wear rate, 1.06 g/N-m; and coefficient of friction, 0.305. The AFM image of Al6061-1.1Al(2)O(3) nanocomposite at optimized condition confirms the improvement in the wear surface smoothness of the nanocomposite compared to Al6061. The optimum parameters of combination setting for Al-Al2O3 nanocomposites obtained are Al2O3 of 1.1 wt.%, load of 34 N, and sliding distance of 2931 m for minimizing specific wear rate and COF by using desirability-based multiresponse optimization technique.