Satish Chinchanikar

TL;DR: A comprehensive literature review on machining of hardened steels using coated tools, studies related to hard turning, different cooling methods and attempts made so far to model machining performance(s) so as to give proper attention to the various researcher works as discussed by the authors.

TL;DR: In this paper, a brief overview on tool condition monitoring is provided, which is of particular importance in metal cutting owing to its direct impact on the surface quality of the machined surface and its dimensional accuracy, and consequently the economics of machining operations.

TL;DR: In this article, the authors investigated the effect of work material hardness and cutting parameters during turning of hardened AISI 4340 steel at different levels of hardness and found that higher cutting forces are required for machining harder work material.

Abstract: This study investigates the effect of workpiece hardness, cutting parameters and type of coating (coated tool) on different machinability aspects like, the tool life, surface roughness, and cutting force and chip morphology during turning of hardened AISI 4340 steel at different levels of hardness. Cutting forces observed to be higher for harder workpiece and for CVD applied multi-layer MT-TiCN/Al 2 O 3 /TiN coated carbide tool. Better surface finish observed for harder workpiece and for PVD applied single-layer TiAlN coated carbide tool. However, better tool life obtained by CVD coated tool can be attributed to its thick coating and the protective Al 2 O 3 oxide layer formed during cutting, which has protected the tool from severe abrasion at elevated temperatures. Modified Taylor tool life equation indicated that the workpiece hardness followed by the cutting speed and depth of cut as the most influencing factors on tool life. The better performance of CVD coated tool under study is obtained by limiting the cutting speed to 300 and 180 m/min for workpiece hardness of 35 and 45 HRC, respectively. However, the upper limit is of 200 m/min when using PVD coated tool. It has been observed that the tool wear form and the wear mechanism(s) by which the tool wear occurred are influenced by the workpiece hardness, cutting conditions and the type of tool.

TL;DR: In this article, experimental investigations carried out to assess the applicability of HiPIMS (High Power Impulse Magnetron Sputtering)-coated carbide tools to hard turning (55 HRC) and to address the widely debated topic about the use of coolants in hard turning are presented.