Taguchi grey relational analysis for parametric optimization of severe plastic deformation process

Abstract

In this paper, a new effective approach, Taguchi grey relational analysis has been applied to experimental results in order to optimize the severe plastic deformation process parameters with consideration to multiple performance measures. The approach combines the orthogonal array design of L27 experiments with grey relational analysis. Grey relational analysis is adopted to determine the best process parameters that give ultrafine grain structure leading to enhanced mechanical properties. The response table and the grey relational grade for each level of the process parameters has been established. The parameters that were considered were the specimen thickness of 3 mm, 4 mm and 5 mm; the displacement rates of 1.0 mm/min, 1.5 mm/min and 2.0 mm/min; and the number of passes which were 1, 3 and 5. A total of 27 experiments were conducted. The optimum parameter values producing the highest value of grey relational grade was allotted rank one which pertained to the factors setup for experiment number 17 having 1.5 mm/min as the displacement rate, with 5 numbers of pass and thickness of specimen being 4 mm.