Analysis of the Effect of Preset Surface Texture on Hard State Cutting

Abstract

When cubic boron nitride (CBN) tools are used for hard cutting hardened steel, a large cutting force is generated. This is accompanied by a large amount of cutting heat, resulting in serious tool wear. In this study, we combined surface weaving technology with hard cutting. Design simulations and experiments were performed on three-factor untextured orthogonal cutting by considering parameters such as depth of cut, cutting speed, and feed. Subsequently, the simulation and experimental data were analyzed by using the polar difference, variance, and signal-to-noise ratio methods to determine the best combination of cutting parameters and the degree of influence of each parameter on the cutting force generated during hard cutting. Hardened GCr15 steel with preset surface texture was hard cut using the optimal combination of cutting parameters. Consequently, tool wear was observed, and the cutting forces were measured. The results were compared with those obtained from the equivalent cutting conditions without texture. The results revealed that a minimum cutting force of 71.48 N was obtained in the untextured cutting experiment. Additionally, a minimum cutting force of 44.64 N was measured in the preset surface texture cutting experiment under the same conditions, which was approximately 37.55% lower than the result obtained in the untextured cutting experiment. The tool wear was much higher for untextured cutting than for preset surface texture cutting. The comparative experiments performed, with and without texture, indicated that a combination of surface texture technology and hard cutting can effectively reduce the cutting forces and tool wear and improve tool life.

Surface Roughness, Topography, Accuracy, Chip Formation Analysis & Investigation of M390 and M398 Steels after Hard Machining

“…The first chip diagram (see Tab. ), or rather from the chip analysis results that for both materials (M390 and M398), and also for both used cutting inserts (DNMG 110408E-NMR T9315 and WNMG 080408E-NF T9315) the chip is cut and segmented, according to [19], what means that the chip is smooth from the rake face of cutting insert, because tangential strains are higher than normal strain, but also the chip is divided to segments. This type of chip is characteristic for tough materials and machined surface is smoother as for torn chip.…”

“…The effect of cutting speed on the life aspects of a PCBN cutting tool in hardened steel turning has been addressed by Kundrák et al [17] and Zhao Ch. et al [19]. In their research, he came to the knowledge that as the cutting speed decreases, the material process of breaking off becomes more and more intense, deteriorating the working surface of the cutting tool more and more.…”