Micro Irregular Hole Slotting by Ultra Sonic Vibration Machining Method (A Study on Multi-stroke Micro Groove Slotting for Forming Micro Irregular Hole)

Abstract

The aim of the study is to establish the machining methods for the small-size irregular holes with high precision profile of finished surface by multi-stroke groove slotting. The groove slotting experiments are conducted by single-stroke and multi-stroke process and assisted by ultra sonic vibration. As the results, by the effect on decrease of cutting force due to the ultra-sonic vibration, it is able to improve finished surface of stainless steel SUS304 with better straightness and roughness. From the time response analysis, the tendency for the tool tip with large rake angel to plunge into the workpiece because of the low stiffness of tool tip and as a result the straightness of finished surface is degraded. It is difficult to improve the straightness of deep grooving with ten strokes slotting and same depth of cut per stroke due to the work hardening effect of SUS 304 and the stiffness of tool tip. However, the straightness of 6 μm by using the small width of cutting tool and the low stiffness tool is able to accomplish due to the keeping mechanism of ultra-sonic vibration to the cutting direction. From these results, the techniques for micro irregular slotting are established.