A review of diamond synthesis, modification technology, and cutting tool application in ultra-precision machining

Diamond is the hardest natural material, boasting a variety of remarkable properties. However, due to increased demand and technological advancements, natural diamond has struggled to meet the specialized requirements of various industries. This paper offers a comprehensively critical review of diamond synthesis, modification, and cutting tool in ultra-precision machining based on the remarkable properties of diamond. Firstly, the paper outlines the outstanding properties of diamonds and breakthroughs in the original performance achieved by doping elements. Secondly, the paper focuses on recent progress in high temperature high pressure (HTHP), specifically those involving solvent-catalysts and element catalysts. The advancements in chemical vapor deposition (CVD) for diamond synthesis, emphasizing improvements in growth rate and quality, are thoroughly reviewed and summarized. Thirdly, the mechanisms of boron doping and interface modification are analyzed. Finally, the paper presents the fabrication of diamond tools and their wear mechanisms during the machining of difficult-to-cut materials and explores assisted-machining methods. Notably, the future direction of diamond synthesis will emphasize producing large-sized diamond with high growth rates, as well as doping and the preparation of diamond/metal composite materials. This critical review provides a comprehensive review of diamond preparation, modification, and cutting tools in ultra-precision machining. It serves as a valuable reference for relevant research endeavors.