Effect of machining parameters on surface roughness and white layer during magnetic field assisted powder mixed EDM of AA6061

Surface integrity aspects of components during machining is one of the challenges of today's manufacturing industry. Magnetic field assisted powder mixed EDM (MFAPM-EDM) is a hybrid process, which integrates the assistance of magnetic field and powder mixed in dielectric in an EDM process towards improving the machining performance and surface integrity. In the present experimental work, machining of aluminium 6061 alloy was performed with fabricated MFAPM-EDM setup considering one variable at a time in the experimental design. Effects of machining parameters namely, discharge current, spark on duration, concentration of powder, spark off duration, and magnetic field have been studied on responses viz. surface roughness (SR), thickness of white layer (TWL) and surface morphology of machined surface. Decrease in SR and TWL was observed with decrease in discharge current, spark on duration, and increase in concentration of powder and magnetic field. Machined surface micro-structural analysis using SEM revealed the presence of fewer cracks, craters and re-solidified debris.