Polycrystalline diamond tools fabrication by micro EDM and their application of brittle material machining

Abstract

The polycrystalline diamond(PCD)tools are widely used for the brittle and non-ferrous materials such as glasses, ceramic and titanium alloy machining. Even many researches have been studied on PCD tools design for high efficient and high-quality brittle materials machining. However, the parameters of PCD tools cutting characteristics are not so clear in some previous researches. According to the former researches studies, one of the biggest challenges in the processing of brittle materials is design and selection of cutting tools, there are different tool design criteria in brittle material because of the different removal mode.In this paper, serval different types PCD end milling tools such as radial, side radial, dual-notch and pyramid-shaped types are designed for brittle materials machining. Electrical discharge machining (EDM) with RC pulse generation circuit was used to fabricate the PCD end milling tools. A dual spindle CNC machining center with both functions of EDM and mechanical cutting was setup to evaluate the brittle materials milling process. Experimental results show that the PCD end milling shape edge is changeable with different capacitance of the RC discharge circuit. It is possible to fabricate varieties of PCD tools by micro EDM and the brittle and non-ferrous materials milling or cutting process could be carried out on the same machine.