Optimization of Drilling Process in Heat-Treated Al–20% SiC Functionally Graded Composite Using Grey Relational Analysis

The objective of this work is to fabricate SiC particle-reinforced aluminium functionally graded metal matrix composite (Al-FGMMC) and optimization of drilling process parameters using grey relational analysis in the heat-treated FGMMC specimen. The A356–20% SiCp-reinforced functionally graded composite has been fabricated by liquid metal stir casting technique followed by the vertical centrifugal casting process. The microstructural evaluation indicated that the maximum reinforcement concentration was found at the outer periphery of the disc. The composite specimens were heat-treated and Ti–Al–N-coated carbide tool was used for the drilling studies. The effect of drilling parameters such as cutting speed, feed, point angle and three different zones (15, 45 and 75 mm from the outer periphery) on the surface roughness and thrust force was analysed using grey relational analysis. Analysis of variance (ANOVA) was also employed to study which drilling parameters significantly influence the drilling process. The results revealed that speed had the highest significance on the drilling process followed by feed, point angle and zone distance.