Research into Chip Flow and Tool Wear in Hard Cutting Using Tool with Variable Strengthening Edge

doi:10.3901/JME.2019.19.195

Abstract

Abstract: The edge chamfered structure not only enhances the strength of cutting edge, but also increases the thermal load in the cutting process, which affects the chip flow, tool wear and machining surface quality in hard cutting. The high-speed photography is used to compare the characteristics of chip flow from the two PCBN tools respectively with variable strengthening edge and invariable chamfered edge, and it is found that the variable strengthening edge can effectively coordinate chip flow, and get rid of chip accumulation in hard cutting. Through the hard cutting experiment, the wear characteristics of the PCBN tool with variable strengthening edge are researched. The results indicated that the wear zone is relatively concentrated for the tool with invariable chamfered edge, while the one is narrow and long for the tool with variable strengthening edge, and especially the flank wear belt is a long triangle. Thus, the latter has better cutting edge retention and tool durability. When the edge form got to change, the flank wear mechanism gradually is changed into a mixture of abrasive, oxidation and diffusion wear from the abrasive wear. The tool with variable strengthening edge is obviously advantageous in improving chip flow and increasing tool life. Thus its widespread application is promising.

Key words: hard cutting, variable strengthening edge, PCBN tool, chip flow, tool wear

CLC Number:

TG501

CHEN Tao, SONG Lixing, LI Suyan, GUO Jian, LIU Xianli. Research into Chip Flow and Tool Wear in Hard Cutting Using Tool with Variable Strengthening Edge[J]. Journal of Mechanical Engineering, 2019, 55(19): 195-200.

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