单晶金刚石车刀在超精密单点切削中的磨损分析

Wear of Diamond Cutting Tool in Ultra-precision Single Point Turning

通过金刚石单点切削试验 ,考察了对无氧铜、铝合金和单晶硅进行超精密单点切削时金刚石刀具的磨损行为 ;分析了刀具磨损对被加工材料表面粗糙度的影响 ;并应用光学显微镜和原子力显微镜对刀具的不同磨损形态进行了宏观和微观观测 ;结合热力学、化学反应磨损和机械磨损的分析方法 ,对金刚石车刀在切削 3种材料时的不同磨损机理进行了实验研究和理论分析 .结果表明 ,为了减轻甚至消除金刚石刀具的磨损 ,在切削铜时应使用少氧或无氧的切削液 ;在切削铝时应在刀具表面涂覆润滑剂或隔离膜 ;在切削单晶硅时应保证低温和少氧环境 .

The wear mechanisms of monocrystalline diamond cutting tool in ultra-precision single point diamond turning of aluminum alloy, OFHC copper and single crystal silicon were investigated. The effect of tool wear on the diamond turned surface roughness was examined, and the macro and micro tool wear morphologies were observed using an optical microscope and atomic force microscope. By combining the test with the theoretical analysis in terms of thermodynamics, chemical reaction and mechanical abrasion, the wear mechanisms of the diamond cutting tool in ultra-precision turning aluminum, copper and silicon were comparatively analyzed in detail. As the results, the diamond cutting tool was characterized by different features in turning different materials. It was suggested to abate the cutting tool wear under reduced oxygen environment or using oxygen free coolant in turning of copper. In turning aluminum alloy, some kinds of inhibitor such as lubricant or isolated surface layer should be applied, while in turning of single crystal silicon, the processing should be performed in the reduced cryogenic or oxygen environment. In addition, the reasonable small depth of cutting and feed rate should be applied to eliminate the vibration impact and suppress the mechanical wear of the diamond tool.