Grey Relational Analysis-Based Optimization of Machining Processes: a Comprehensive Review

Process optimization deals with identifying the optimal settings of input parameters of different machining processes resulting in most efficient utilization of energy and other resources, and less perilous effects on the machine operators ensuring sustainable manufacturing environment. Various mathematical tools, mainly in the form of multi-criteria decision-making techniques, have been adopted for optimizing the machining processes. Among them, grey relational analysis (GRA) appears as the most potent one due to its simple computational steps and independency on criteria weights. In this paper, a comprehensive review is carried out on the applications of GRA technique for parametric optimization of some of the industrially well-accepted conventional and non-conventional machining processes. The essence of 227 research articles (published during 2002-2022) from Scopus and other databases is also critically analyzed with respect to adoption of different experimental design plans, work materials machined, input parameters and responses considered, combination or comparison of GRA with other methods, journal-wise publication, authors' nationality, institution-wise publication, link with other keywords, and collaborative research works across the globe. This review paper would thus help the decision-making community in exploring the application potentiality of GRA in machining processes optimization leading to sustainable manufacturing environment. Some of the future research directions are also proposed.