Optimization of Machining Parameters in Turning Magnesium Alloy with PCD Tool

Magnesium alloy is one of the lightest materials currently finding wide applications in the production of aircraft engines, airframes, helicopter components, light trucks, automotive parts and computers parts due to its attractive properties. The difficulty in machining mg alloys with regular cutting tools like high speed steel (HSS), carbide tools requires new cutting tools to be tried. The surface finish is a key quality characteristic in dry turning of magnesium pieces and is often affected by multiple factors within the machining process. In this attempt Mg AZ91D alloy is machined with polycrystalline diamond (PCD) coated cutting tool and the effects of input parameters like cutting speed, feed and depth of cut were studied to evaluate the surface roughness obtained. The input parameters were optimized using Taguchi techniques. It was found that the parameter having greatest influence on the surface roughness was feed rate followed by depth of cut and cutting speed.