Experimental comparison of carbon-dioxide and liquid nitrogen cryogenic coolants in turning of AISI 1045 steel

This experimental work is carried out to investigate the performance and influence of cryogenic coolants such as CO2 (carbon dioxide) and LN2 (liquid nitrogen) on cutting temperature, cutting force, tool wear, surface finish and chip morphology in machining of AISI 1045 steel compared to wet machining. The results proved that the application of cryogenic coolants reduced the cutting temperature drastically which resulted in appreciable improvement in surface finish of the product and reduced tool wear. The use of cryogenic LN2 reduced the cutting temperature about 3–17% when compared to CO2 coolant. Application of CO2 reduced the cutting forces and improved the surface finish of the machined part to an extent about 2–12% and 2–14% respectively when compared to the use of cryogenic LN2 coolant. Tool wear was found to be less on the application of CO2 compared to the wet and LN2 machining conditions.

► Cryogenic cooling resulted in reduction of cutting temperature than wet machining.
► Reduction in cutting forces was observed under cryogenic cooling conditions.
► High reduction in the tool wear was observed during cryogenic CO2 cooling.
► Better surface finish and chip control was observed under cryogenic application.