半球状極微粒ダイヤモンド電鋳工具に対する砥粒平坦化ツルーイング技術

摘要

マイクロ切削加工と異なり，マイクロ研削加工は硬rn脆材料に対して超精密・微細形状を作る潜在能力をもrnっている．しかし，耐欠損性や耐摩耗性に優れた研削rn工具の開発が遅れていることや平滑な加工面を作るこrnとが容易でないことなどが原因で，微小径の研削工具rnを高速回転させて用いる方式でのマイクロ研削加工はrnほとんど実用化されていない．%A truing technique for fabricating the tip of an electroformed diamond tool of 0.1 mm diameter and 4 μm mean grain size with a hemispherical shape and flattening the cutting edges of diamond grains on the tool working surface was developed. A polycrystalline diamond (PCD) tool of 0.5 μm diamond grain size and 10 mm diameter was employed as a truer. It was confirmed through the truing test that the rough surface of the PCD truer generated by electric discharge truing should be partially flattened to eliminate scratches and removed chips adhering onto the tool working surface. In addition, truing conditions that enable the flattening of sharp cutting edges on a tool working surface along the hemispherical tool profile were determined by conducting a truing test in which both the revolution speed of the tool and the rotation speed of the truer were varied.