Effect of Cryogenic Cooling on the Surface Quality and Tool Wear in End Milling 6061-T6 Aluminium

The vast majority of machining operations use some type of cutting lubrication to facilitate improved machinability, which also constitutes reductions in surface roughness and increases in tool life. This occurs as a function of reducing the temperature at the cutting interface or zone and by providing a fluidised cushion between the cutter and the cutting interface. This also aids in improving chip formation and chip morphology. However, the major drawback of using conventional coolant is the increased environmental impact of coolant recycling. Other methods have been recently investigated and include chilled air and cryogenic methods. This paper provides one of the first attempts at using cryogenic coolant and lubrication methods for CNC milling of T6 aluminium using carbide tooling. The results suggest that using cryogenic methods provides a realistic alternative to conventional coolants for milling applications that is not only more environmentally friendly, but also reduces the surface roughness, provides better chip formation and increases tool life.