Investigation on Tool Wear and Surface Characteristics in Hard turning under Air-Water Jet Spray Impingement Cooling Environment

Low cost machining puts tremendous pressure on the research in machining hardened steel compared to traditional grinding. As environmental regulations are strict enough on application of cutting fluids, a novel method called spray impingement cooling (SIC) assisted hard turning has been studied. The current work explores the distinguish wear modes, surface characteristics, chip-tool interface temperature and chip morphology in turning of AISI D2 steel by coated carbide tools (TiN/TiCN/Al2O3/TiN). The results revealed the favorable chip tool interaction during machining in context to surface roughness, surface topology, flank wear, chip morphology, chip reduction coefficient and tool life. In the SIC, evaporation occurred due to atomization of water jet and sufficient to generate significant cooling as maximum temperature has been found as 200.6 0C. Modes of wear like abrasion, chipping and catastrophic breakage are noticed at tool-tip in hard turning. The optimal settings of parameters are founds as ap1-fn1-vc2 i.e. depth of cut-0.1 mm; feed-0.04 mm/rev; cutting speed-108 m/min. At these parametric conditions, the measured tool life is found as 20.3 minutes.