Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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A study on optimal cutting conditions of MCD or NCD coated ball end-mills for finishing

MCD 및 NCD 코팅 볼 엔드밀의 정삭가공에서의 최적절삭조건에 관한 연구

  • Jong-Su Kim (Korea Institute of Industrial Technology, Research Institute of Advanced manufacturing & materials Technology)
  • 김종수 (한국생산기술연구원 뿌리기술연구소)
  • Received : 2022.11.14
  • Accepted : 2022.12.31
  • Published : 2022.12.31
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Abstract

Recently, several studies are being conducted to achieve a curvature of 180° or more for the edge of the display glass. The thermocompression molding process is applied to the manufacture of curved glass, and high hardness G5 graphite is used as the mold material to withstand the impact applied to the mold. G5 graphite has high hardness and strong brittleness, which makes tool wear and surface damage easy during machining. Therefore, the demand for diamond-coated tools with good mechanical properties is increasing in the G5 machining field. In this study, the optimal cutting conditions and machinability of a nanodiamond (NCD) coated ball end mill being developed by a tool manufacturer were analyzed and evaluated. For this purpose, the same test was performed on the microdiamond (MCD) coated ball end mill and compared together. In summary, the machinability of MCD and NCD coated tools showed better cutting performance at a cutting speed of 282 m/min, a feed rate of 1,400 mm/min, and a radial depth of cut of 0.08 to 0.1 mm.

Keywords

Acknowledgement

본 연구는 산업통상자원부의 소재부품기술개발사업 (20017218)의 지원을 받아 수행되었습니다.

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