Evaluation of the mechanical and tribological characteristics of AA6061/TiB2 metal matrix composite and parametric optimisation of its casting process by using Taguchi technique and NSGA-II

Abstract

The present research work proposes an experimental methodology and optimisation strategy of the process parameters for fabrication of AA6061/TiB2 composite by stir casting technique. The aim of this work is to find influence of process parameters viz. weight fraction of TiB2 (8%, to 12%), stirrer speed (400 rpm to 700 rpm) and casting temperature (725°C to785°C) on hardness and wear of the composite. Taguchi's L-27 is used for design of experiments. To investigate the presence of TiB2 particles and its dispersion in molten metal matrix XRD and microscopic observations were carried. The analysis of variance (ANOVA), signal to noise ratio (S/N) was calculated to determine the contribution of each process parameter towards improved mechanical properties and best set of process parameters. Thereafter, confirmation test was carried to validate the result obtained in ANOVA with experimentation. Non-dominated sorting genetic algorithm (NSGA-II) is used to optimise the process parameters of composite fabrication.