Increase of process reliability of ultra-precision cutting through direct temperature measurement in cutting parts form single crystal diamond by use of Boron-doping

超精密加工是制造汽车、医疗或航空航天应用的光学元件的既定工艺。使用刃口半径为rβ≤50 nm的单晶金刚石工具可实现光学和功能表面，如反射镜、光栅或透镜。尽管金刚石的机械硬度很高，但在切割过程中存在磨损现象。为了描述和解释金刚石在切削区的磨损过程，需要分析切割温度。目前，金刚石工具上的温度还没有得到充分的调查。在分辨率和响应时间方面缺乏合适的温度测量方法是采用这种新方法的原因。该项目的目的是测量钻石切割区的温度。这是通过使用离子束掺硼金刚石工具的电传感特性来实现的，这使得能够在没有延迟时间的情况下在钻石工具的切削区进行直接测量。第一个工作周期的结果表明，离子注入金刚石工具测量温度的基本可操作性是可能的。然而，由于硼的分布太不均匀，因此无法测量切削区的温度。因此，第二个工作周期的目的是使用一种更精确的方法将具有定义形状的结构引入钻石。这种方法的优点是切削区温度测量的灵敏度较高，避免了金刚石的强烈爆裂，并具有更好的可磨性。工作计划包括研究掺硼结构的特征和特性，以及可能用于超精密切割过程的工作窗口。必须设计和开发一套完整的测量装置来确定切割区的温度。在此基础上进行了实验研究，考察了切削区的温度。同时，进行了有限元仿真，验证了计算结果。

Ultraprecision machining is an established process for manufacturing of optical components for automotive, medical or aerospace applications. The use of single crystalline diamond tools (SCD) with cutting edge radius rβ ≤ 50 nm realise optical and functional surfaces such as mirrors, gratings or lenses. Despite the high mechanical hardness of diamond, there are wear phenomena during the cutting process. To characterize und interpret the wear processes of the diamond in the cutting zone, cutting temperatures need to be analysed. Currently, the temperature on a diamond tool is not fully investigated. The lack of suitable temperature measurement methods regarding resolution and response time are the reason for this new approach. The aim of the project is to measure the temperature in the cutting zone of the diamond. This is done by the use of the electrosensory features of the ion beam boron-doped diamond tool which enables a direct measurement in the cutting zone of the diamond tool without delay time. The results from the first working periode indicates that the basic operability from ion implanted diamond tools to measure the temperature is possible. Yet, there is no possibility to measure the temperature in the cutting zone since the distribution of the Boron is too inhomogeneous. Therefore, the aim of the second working periode is to use a more accurate method to introduce structures with a defined shape into the diamond. The advantages from this method are a higher sensitivity of the temperature measurement in the cutting zone, avoidance of strong bursts of the diamond and a better grindability. The work programm includes an investigation of the features and characteristics of the boron-doped structures and of a possible workwindow for the ultra precision cutting process. A complete measurement setup has to be designed and developed to determine the temperature in the cutting zone. Building on this, experimental investigations are conducted which examine the temperature in the cutting zone. Simultaneously, FEM-simulations are carried out to verify the results.