Abstract
For precision machining of fuel injection nozzles, a micro-drilling process to drill micro-holes <0.2 mm in diameter is required. In this study, a non-step drilling method for high-efficiency processing is developed. Previously, the effects of drill feed rate were verified to measure thrust force and torque during drilling, and the results indicated that a high feed rate capable of keeping chips to a continuous form was optimal. Here, the cutting performance of the non-step drilling method was investigated by experiments. Machining tests indicated that use of a diamond-like carbon (DLC)-coated drill for chip exhaust out of the drilling hole of the micro-drill allowed a higher feed rate to be applied.
