Production of Aluminum 6063 Metal Matrix Composite with 12% Magnesium Oxide and 5% Graphite and its Machinability Studies using Micro Electrochemical Machining

Hybrid Aluminum Metal Matrix Composites (AMMCs) are finding application in aerospace and automobile industries for its light weight.In this research hybrid AMMCs with 12% magnesium oxide (MgO) and 5% graphite (Gr) were fabricated and mechanical properties were studied.The compressive strength, bending stress frictional force, impact strength are found to be 292.94N.mm -2 , 1.31 N.mm -2 , 11.3 N (maximum) J.m -2 = 0.4x10 5 respectively.Moreover the highest hardness values are obtained during Brinell and Rockwell testing's 127.23 BHN, 59 HRB respectively.Machinability studies using micro electrochemical machining (micro ECM) is performed on the hybrid AMMCs by varying the voltage, electrolyte concentration, duty cycle and electrolyte temperature.L9 Orthogonal array (OA) is conducted and the experimental results are analyzed using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method.Based on the TOPSIS analysis the optimal combination for the higher MRR and lesser OC is 9 V,25 gm.L -1 ,80 % duty cycle and 35º C electrolyte temperature (A2B2C3D1).Analysis of Variance (ANOVA) shows that the duty cycle is the most significant factor followed by voltage and electrolyte temperature for higher material removal rate (MRR) and lower overcut (OC).