Effect of cryogenic coolant on turning performance: a comparative study

Abstract

In the recent years, environmental regulations became stringent in terms of disposal of chemically contaminated conventional coolants. Cryogenic cooling is an alternative technique to the conventional cooling technique with conventional coolants. In this work, new findings were reported in turning of 17-4 precipitation hardenable stainless steel (PH SS) at varying feed rate conditions under cryogenic cooling and the results were compared with the minimum quantity lubrication (MQL), conventional wet and dry cutting conditions, respectively. Turning performance considered in this work includes cutting temperature, surface roughness and tool wear. From the findings, it was noticed that a maximum of 24%, 26% and 69% reduction in surface roughness was observed in cryogenic machining when compared to MQL, wet and dry environments, respectively. Also, the maximum flank wear reduction found in cryogenic machining was 42%, 48% and 53%, respectively, over the MQL, wet and dry environments. Overall, it was concluded that cryogenic machining is a feasible method for improving the turning performance characteristics in machining of 17-4 PH SS.