Machinability analysis and characterization of aluminium hybrid metal matrix composite using WEDM

Abstract

The aluminium composites are being used for various number of applications like automobiles, aerospace, marine, construction, etc. Manufacturing industries keenly focus on improving their product quality by means of strength with reduction in cost. The hybrid metal matrix composites paved way for achieving those objectives through reinforcement of existing traditional materials. This work is also a novel approach of examining the suitability of aluminium alloy for aerospace and automobile application, by reinforcing with various proportions of Silicon Carbide (SiC) and Graphite (Gr). 5, 10 & 15% of SiC in combination with graphite of 1 & 2% by weight basis. Further the casted composite was explored for its machinability in Wire cut electrical discharge machining (WEDM) process. Voltage and current are the two control parameters chosen for the study with responses material removal rate and Kerf. The MRR is proportional to the production time and Kerf is proportional to dimensional accuracy. A hybrid Taguchi-GRA optimization technique was utilized for identifying optimal parameters for achieving the objective functions. Improved machining performance was shown by the composite containing 15% SiC and 1% Gr over the operating range of 65V and 3A in WEDM process. Finally, the optimized values were justified by using SEM imaging. The agglomeration occurs at 15% SiC addition to base aluminium metal.