An experimental study on MQL assisted high speed machining of NiTi shape memory alloy

Abstract: Nickel Titanium (NiTi) shape memory alloy is a prominent material for biomedical implants. Machining of shape memory alloy is challenging and requires intervention of sustainable techniques to produce quality products with minimum environmental footprints. This paper details the results of experimental investigation conducted on MQL assisted high speed machining of shape memory alloys. It reports the effect of MQL parameters on surface roughness and tool wear during turning (at speed 90 m/min) of NiTi shape memory alloy. Experiments are conducted based on Taguchi’s robust design of experiment technique with L9 orthogonal array. Rhomboid shaped simple carbide tool is selected for experimentation. Green lubricant which is a blend of natural, synthetic and sulphurized esters is used as MQL fluid. Three important MQL parameters such as flow rate, air pressure, and nozzle distance are varied at 3 levels each. Parameters are optimized to secure the optimum combination producing best surface finish (Ra~1.39μm) and tool flank wear 1.6 mm