Performance analysis of cryogenically treated and Ti Al N coated cermet cutting tools

Abstract

Machining hardened steel parts has become more popular in the newlinemanufacturing industries. The manufacturing methods like dry machining and newlinehard machining is applied for higher productivity which requires advanced newlinecutting tools like carbide and cermet. Tool wear is the main criterion to newlineevaluate the performance of tools used for hard turning. In order to improve newlinethe performance of the cutting tools, various coatings materials and methods newlinewith and without cryogenic treatment were attempted. From the literature newlinereview, it was found that cryogenic treatment has been acknowledged as a newlinemeans of extending the tool life of many cutting tools and a lot of newlineexperimental work has been carried out with various types of cryogenically treated tungsten carbide cutting tools. Whereas very little work has been newlinecarried out to study the effect of cryogenic treatment and Ti-Al-N coating on newlinecermet tool and pre/post-cryogenic treatment on Ti-Al-N coated cermet tools. newlineHence, in this study, attempts had been made to evaluate the newlineperformance of cermet cutting tools either plain (UCandUT) or subjected to Ti- newlineAl-N coated (UTandC), cryogenically treated (UCandT) and cryogenically newlinetreated before Ti-Al-N coating (CandT) and cryogenically treated after Ti-Al-N newlinecoating (TandC) on machining hardened AISI 4340 steel (HRC 45) and newlinehardened AISI D2 steel (HRC 50). The experiments were conducted under newlinevarying cutting conditions. The performance of the cermet tools were analysed in terms of flank wear, surface roughness of machined workpiece, newlinecutting force and chip formation during machining. newlineThe plain cermet (UCandUT) tool produced high wear, surface newlineroughness and cutting forces in comparison with other cermet tools on newlinemachining AISI 4340 steel.This is because of the plain cermet is subjected to newlinesevere plastic deformation, results in formation of irregular serration and newlinesticking contact between tool - chip. newline