Determination of optimal performance in wire electrical discharge machining of Al/Al₂O₃/22_p composites using response surface methods and grey relational analysis

ABSTRACT

In this study, wire electrical discharge machining of aluminium matrix composites has been experimentally investigated. A metal matrix composite Al/Al₂O₃/22 _p has been machined at various combinations of machining parameters such as pulse on-time, off-time, wire speed and wire tension. Empirical models have been developed to predict the cutting rate, surface roughness and kerf width of the machined composite material. The models were developed by using the technique of response surface methodology. The experiments were conducted in standard roughing mode by using carefully planned response surface design matrix (central composite design). The model predictions are in good agreement with the experimental results. The R² values of the proposed cutting rate and kerf width models are above 0.99, where as it is 0.98 for the surface roughness model. The pulse on-time was found to influence cutting rate and surface finish significantly. Kerf width was found to be affected by pulse on-time, off-time, wire speed and wire tension. In addition, a model was developed to correlate the multiple performance characteristic called as grey relational grade and the process parameters. The grey relational grade was significantly affected by pulse on-time and off-time time. The R² value for the grey relational grade model was 0.94. Optimal parameter setting was determined for the multiple performance characteristic. The improvement in cutting rate was significant with reasonably smooth surfaces and narrow kerf width. However, the surface finish was found to be dominated by the presence of protruding ceramic particles on the machined surfaces.

KEYWORDS:

• W.E.D.M.
• M.M.C.s
• response surface modelling (R.S.M.)
• surface finish
• composite machining
• grey relational analysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

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Nilesh G. Patil

Nilesh G. Patilis a Professor of Mechanical Engineering and also in the position of Director of the institute. He has, so far, more than 55 publications to his credit including 03 book chapters. He has also completed two minor research projects and one major project is in progress.  He has also successfully guided 01 Ph.D. scholar and 17 M.Tech projects. At present, 6 research scholars are working under his supervision. His current research interests include sustainable manufacturing processes, Additive Manufacturing and Processing of advanced materials such as CMCs and MMCs.