A focused ion beam (FIB) is an effective means of fabricating micro-to submicro-scale shapes on diamond cutting tools. However, ion irradiation of diamond tools causes ion implantation, defects, and non-diamond phases, all of which degrade the tool performance. To remove affected layers from FIB-irradiated diamond tools, heat treatment in air was applied, and the effect of the heating parameters on the etchability of the irradiated area was investigated. It was found that the affected layer could be etched and removed from the diamond tool surface, even at 500 °C. In machining experiments on aluminum alloy and nickel phosphorus, machining performance was improved by the applied heating technique, and the cutting forces and machined surfaces were similar to those obtained with the non-irradiated tool. These results indicate that the proposed heating technique is effective for diamond cutting tools shaped by FIB.
Investigation of focused ion beam induced damage in single crystal diamond tools