Cryogenic High Speed Machining of Cobalt Chromium Alloy

Cobalt chromium (CoCr) alloys are extensively used in medical industries for a variety of applications. Due to their unique material properties, machining CoCr alloys are associated with short tool life, poor surface quality and low productivity. This paper presents one of the first studies on using various cooling methods in CNC milling of these alloys. A series of machining experiments were conducted at 200m/min cutting speed. Cryogenic cooling, minimum quantity lubricant (MQL) and flood cooling with water-based emulsion were investigated. The analysis clearly demonstrated that a 71% reduction in surface roughness Ra and a 96% reduction in flank wear can be achieved using cryogenic cooling when compared to conventional machining best practice.