Effect of high speed end milling of Co-28Cr-6Mo cobalt chromium molybdenum alloy using uncoated and coated carbide tools

Abstract

Cobalt chrome molybdenum alloys are advanced materials which are considered difficult to cut material due to their unique combination of high strength, high toughness, high wear resistance and poor thermal conductivity. High speed end milling was performed experimentally to access the machinability of Co-28Cr-6Mo alloy at different cutting speeds of 80 and 120 m min-1 using uncoated and coated carbide cutting tools. Tool wear, tool life and surface roughness were recorded analyzed accordingly. Results showed that higher cutting speed significantly reduces the tool life due to rapid tool wear. Uncoated carbide tool outperformed coated carbide with respect to tool life. It was also found that surface roughness at higher speed was slightly lower than at lower cutting speed for both coated and uncoated tools.