CVD金刚石厚膜电加工表面粗糙度分析

Analysis on Surface Roughness of Electromachined CVD Diamond Thick Film

由于化学气相沉积(Chemical Vapor Deposition,简称CVD)金刚石厚膜的加工极其困难,本文提出了一种金刚石厚膜精加工的新工艺,即通过掺杂使金刚石膜导电,利用电火花对掺杂金刚石膜进行加工。掺杂后金刚石厚膜电阻率范围达到0.00243-0.0634W×cm,研究了电参数对金刚石厚膜电火花加工表面粗糙度和材料去除速率的影响,结果表明二者都随着峰值电流和脉冲宽度的增大而增大。通过回归计算得出了电火花加工表面粗糙度的经验公式,二元回归分析的相关系数达0.96,证实了经验公式的有效性。

Because of the difficulties in machining CVD (Chemical Vapor Deposition) diamond thick film, a new technology for the finish machining of diamond thick film was proposed. The CVD diamond thick film was made conductive by doping, so that it could be machined by means of EDM. The resistivity of CVD diamond thick film ranged from 0. 00243 to 0. 0634 Ω· cm after doping. The relationship between surface roughness of electromachined diamond thick film, material removal rate and EDM electro parameter was investigated in detail. The results indicated that both the surface roughness and material removal rate increased with the increase of peak current and pulse width. At last, the empirical relationship of the surface roughness for EDM of the diamond film was established, and the correlation coefficient of regression analysis came up to 0. 96, which verified the validity of the formula.