中文摘要：

为了研究氟化钙（CaF2）单晶超精密切削过程中的金刚石刀具磨损及其对切削过程的影响,对CaF2晶体进行了超精密切削实验,系统观测了刀具磨损形貌随切削路程的变化趋势,分析了刀具磨损机理,同时通过分析不同切削路程下切削表面微观形貌和切削力的变化,对刀具磨损与切削模式之间的关系进行了探讨。研究表明,超精密切削CaF2晶体时刀具磨损模式为沟槽磨损和缺口破损,刀具磨损随切削路程的演变过程为后刀面沟槽磨损扩展到前刀面缺口破损,同时相应的切削模式由延性去除转变为脆性去除。该研究结果为大口径CaF2晶体纳米尺度延性域切削提供了技术支持。

英文摘要：

In order to study the diamond tool wear and its effects on the cutting process in ultra-precision cutting of CaF2,the long distance cutting experiments of CaF2 crystals were carried out.The effects of cutting distance on the micrograph of tool damage were observed systematically,the tool damage mechanism was analyzed,the relation between tool damage and cutting model was discussed through analyzing the influences of tool damage on the micrograph of machined surface and cutting force.The research findings show that： the tool damage model in ultra-precision cutting of CaF2 crystals are grooving damage and notch breakage,the development of the tool damage followed with cutting distance is that the tool damage is extended from the grooving damage in flank face to notch breakage in rake face,and the cutting mode is also changed from the ductile mode cutting to brittle mode cutting.The research results supply the technological support for nano-scale ductile mode cutting of large-size CaF2 crystals.