| Diamond has found its wider and wider applications in the field of high technology due to its excellent properties in mechanical, electrical, thermal, optical, acoustical and chemical aspects. Diamond film un-doped is highly insulated and so is not processed by electrical discharge machining method. In order to improve its machining abilities and finally manufacture it by EDM method, diamond film has been doped boron. The main work done in this paper is as follows:1. Fabrication equipment and theory of B-doped diamond film were introduced. Mechanical systems were studied and electric and control systems were designed. Experimental results show that the equipment can deposit B-doped large area high-quality thick diamond film under the control system.2. Fabrication process of B-doped diamond film was set forth. The factors of nucleation and subsequent growth of diamond film were discussed in detail. The Fabrication parameters were preliminarily optimized. The Morphology and composition of the samples of the diamond film for different B/C ratios was investigated by scanning electron micrograph (SEM) and Raman Scattering Spectroscopy (Raman). The content of different levels of B dopant in the diamond film was tested by Secondary Ion Mass Spectrometry (SIMS). The resistivity of the diamond film was studied by means of four-probe method.3. EDM method was adopted to process B-doped diamond film and the process was studied. The Morphology and composition of the machined diamond film was analyzed by SEM and Raman. Surface roughness was measured by surface roughness tester.4. The machining mechanism was investigated. It is comprehensive outcome of melting , gasification, oxidation and surface graphitization. It is demonstrated that EDM method can effectively process B-doped diamond film.
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