Development of ultra-precision orthogonal cutting machine for investigation of micro-cutting process.

本研究的目的是研制一台能用扫描电子显微镜直接观察微切削过程的试验性超精密正交切割机，并通过扫描电子显微镜的切割实验和有限元分析来研究单晶金刚石刀具的微切削过程。研究工作成果总结如下：1.研究成果。超精密正交切割机的设计与开发为了在扫描电子显微镜下直接观察各种材料的微切削过程(切深小于1微米)，新设计开发了一种试验性超精密正交切割机。通过测量和切割实验，对所研制的切割机的精度和刚度进行了评价。扫描电子显微镜微切削加工过程的实验研究利用安装在扫描电子显微镜上的切割机，用单晶金刚石刀具加工了无氧铜和陶瓷。用扫描电子显微镜观察切屑形成过程和加工表面，并测量切削力。微切削过程的有限元模拟新开发了一套基于刚塑性有限元的微切削过程模拟程序。该程序能够模拟切屑形成过程的暂态过程。计算了材料的应力应变和切削力。微切削过程的探讨在实验结果和有限元分析的基础上，从切屑形成、切削力和加工表面的角度对微切削机理进行了探讨。研究发现，切深小于1微米的微细加工工艺不同于传统的微细加工工艺。

The objectives of the present research work are to develop an experimental ultra-precision orthogonal cutting machine for direct observation of micro-cutting process with Scanning Electron Microscope (SEM) and to investigate micro-cutting process with single crystal diamond tools through both the cutting experiments in SEM and the analysis with use of Finite Element Method (FEM). The results of the research work are summarized as follows.1. Design and development of ultra-precision orthogonal cutting machine; An experimental ultra-precision orthogonal cutting machine was newly designed and developed aimed at direct observation of the micro-cutting process (depth of cut is less than 1 <micro> m) of various materials in SEM. The accuracy and stiffness of the cutting machine developed here were evaluated through the measurements and cutting experiments.2. Experimental investigation of micro-cutting process in SEM; Non-oxygenated coppers and ceramics were machined with single crystal diamond tools employing the cutting machined installed in SEM. The chip formation process and finished surface are observed with SEM and the cutting forces were measured.3. Simulation of micro-cutting process with use of FEM; A simulation program was newly developed to analyze the micro-cutting process based on the rigid-plastic FEM. The program is able to simulate the chip formation process in the transient state. The stress and strain of material and the cutting forces are also evaluated.4. Discussion on micro-cutting process; The micro-cutting mechanism was discussed from the viewpoints of the chip formation, the cutting forces and the finished surface on the basis of both the experimental results and the FEM analysis. It was found that the micro-cutting process with depth of cut of less than 1 <micro> m is different from the conventional cutting process.