The Effectiveness of a Novel Cryogenic Cooling Approach on Turning Performance Characteristics During Machining of 17-4 PH Stainless Steel Material

Abstract

In the present work, a tool holder design has been modified and fabricated, which act as a jet stream tool holder for supplying the cryogenic coolant (liquid nitrogen) to both rake and flank faces of cutting tool simultaneously in a novel way. The present work investigated the effect of cryogenic coolant and turning process parameters on cutting temperature (T), tool flank wear (Vb), material removal rate (MRR) and surface integrity (surface roughness (Ra), surface topography (ST) and microhardness (H)) when it is supplied through the modified tool holder (Mode-I) while machining of 17-4 precipitated hardened stainless steel (PH SS) material and results were compared with the cryogenic coolant supplied at the machining zone with one external nozzle (Mode-II) respectively. Experimental results revealed that Mode-I (proposed cooling approach) significantly reduced the T and Vb wear to a maximum of 61% and 29% respectively when compared to cryogenic cooling with Mode-II approach. It was also found that cryogenic cooling with Mode-I approach affected the surface and subsurface characteristics positively over the cryogenic cooling with the Mode-II approach, which leads to substantial improvement in the final product performance respectively.