Cutting Mechanics of Bulk Metallic Glass Materials on Meso-End Milling

In this study, effect of feed rate on cutting force, burr formation, and surface roughness on milling of Zr-based bulk metallic glass (BMG) material was investigated at constant spindle speed, 5000rpm. Uncoated 1mm diameter solid-WC tools with two cutting edges were used for all tests. Cutting mechanics of helical endmill was examined. Specific cutting and edge coefficients for BMG-WC workpiece-tool pair were identified by using mechanistic approach. Analytically modeled forces converge to the experimentally measured forces with less than 10% error. Cutting forces of BMG were compared with SS304 stainless steel and Al6061-T6. BMG requires cutting force less than SS304 and more than Al6061 under the same conditions. Analyzing of burr formation of slot milling operations showed that the amount of deposited chip formation increases with the increasing feed rate. The rollover and the top burr type of burr formations were observed along the slot. This study concludes that Zr-based BMG can be achieved meso-machining with good surface roughness, (Ra=0.113 mu m), using conventional cutting tools.