COMPARATIVE EVALUATIONS OF SURFACE ROUGHNESS AND CUTTING FORCES DURING HARD TURNING UNDER DRY AND COMPRESSED AIR COOLING MEDIUM

In this present work, an experimental investigation through mathematical modelling was carried out to study the effects of different cooling mediums and cutting parameters on surface roughness and cutting forces, during the hardturning of hardened AISI 52100 steel ( 60±2) HRC. Experiments were performed using PCBN insert under dry and compressed air cooling medium. Experimental observations indicates that hard turning under compressed air cooled condition produced lower values of surface roughness and cutting forces. However, there is no significant effect of cutting speed on the surface roughness. Compressed air lubrication have proved to be more productive with better surface finish and reduced cutting forces. It has been observed that surface roughness gets affected mostly by feed and not by depth of cut. Cutting forces changing randomly as per change in cutting speed.