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

本研究工作的目的是研制一台能直接用扫描电镜观察微切削过程的超精密正交切削试验机，并通过扫描电镜切削试验和有限元分析研究单晶金刚石刀具的微切削过程。研究工作的主要成果如下：1.超精密正交切割机的设计与研制为了在扫描电镜中直接观察各种材料的微观切割过程（切割深度小于1 m），新设计并研制了一台实验用超精密正交切割机<micro>。通过测量和切削实验，对所研制的切削机床的精度和刚度进行了评价.扫描电镜中微细切削过程的实验研究利用安装在扫描电镜中的单晶金刚石刀具对无氧铜和陶瓷进行了切削加工。用扫描电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基于刚塑性有限元法，开发了微切削过程的有限元模拟程序。该程序能够模拟切屑形成过程中的瞬态。对材料的应力应变和切削力进行了分析.基于实验结果和有限元分析，从切屑形成、切削力和加工表面等方面对微细切削机理进行了探讨。研究发现，切深小于1 m的微细切削加工<micro>不同于常规切削加工。

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.