2002 年 68 巻 10 号 p. 1362-1366
Cutting performances of CVD (Chemical Vapor Deposition) diamond coated drills for brittle materials such as single-crystal Si or silicon carbide ceramics were investigated. For drilling of single-crystal Si, only a mere wear of CVD diamond film around the cutting edges was observed, but damage of cutting edges was dominated by chipping. Chipping performances were affected by shape of drill, the chipping of the cutting edges were repressed for the drills with large web thickness and long tool life were obtained. On the other hand, for drilling of silicon carbide, severe wear of CVD diamond film was observed. Major cutting edge showed "knife edge shape". These phenomena are very characteristic as compared with conventional carbide drills.