Effects of cryogenically treated physical vapor deposition-coated tools on the turning performance of nickel-based superalloy

Abstract

In recent years, cryogenic treatment has been applied to improve the performance of cutting tools. Improving the performance of cutting tools can improve the surface qualities of workpiece and reduce costs. Nickel-based superalloys are difficult to machine. It is necessary to improve the machinability properties of these hard-to-machine alloys and to increase the product quality. In this study, the effects of cryogenically treated physical vapor deposition-coated tools on the turning performance of nickel-based Hastelloy C22 superalloy were investigated. Deep cryogenic treatment (−145°C) and shallow cryogenic treatment (−80°C) were applied to the physical vapor deposition-coated tools. Experiments were carried out under dry conditions. The cutting parameters selected for the machining were cryogenically treated cutting tools, cutting speed, and feed rate. The deep cryogenic treatment had a favorable influence on the performance of the physical vapor deposition-coated carbide inserts. Thanks to the deep cryogenic treatment applied to the cutting tools, 99.5% and 19.7% improvement in surface roughness and cutting forces were achieved, respectively, compared to the untreated tool. The deep cryogenic treatment contributed more to the wear resistance of the tools than the shallow cryogenic treatment. A slight increase in the hardness and electrical conductivity of the tools was detected thanks to the cryogenic treatment.