Ultra Precision Machining of Hard to Cut Materials and Composite Materials

针对难加工材料和复合材料的超精密加工过程，对微细加工过程进行了实验和理论分析。本文的主要研究内容如下：1.研制了一种内嵌于塞曼正交式微细加工设备，并将其搭建在扫描电子显微镜上，实现了对切割深度为0.1毫米的微细加工过程的直接观察。对纤维增强金属(FRM)的微加工过程进行了实验分析，阐明了切深和纤维方向对表面光洁度、切屑形成和切削力的影响。对单晶铜的微细加工过程进行了实验观察和分析，阐明了单晶铜的晶体取向和切深对切屑形成、切削力和表面光洁度的影响。单晶铜加工过程的有限元分析提出了一种基于刚塑性有限元的理论方法，分析了单晶铜的正交微加工过程。在切屑形状和切削力方面，计算结果与实验结果吻合较好。对微细加工过程的讨论总结如下：(1)在FRM和铜的加工实验中，当切深小于1um时，获得了良好的表面光洁度。(2)当切深小于1um时，纤维方向和晶体取向不影响切屑的形成过程。(3)成功地将刚塑性有限元应用于单晶铜的微加工过程分析。

Experimental and theoretical analyses of micro cutting process have been carried out aiming at clarifying the ultra-precision machining process of the hard-to-cut materials and the composite materials.1. Development of an orthogonal micro machining equipment built in SEMAn orthogonal micro machining equipment was developed and built in the SEM (Scanning Electron Microscope) in order to realize direct observation of the micro machining process at the depths of cut down to 0.1 mum.2. Experimental analysis of micro machining process of FRMMicro machining experiments of FRM (Fiber Reinforced Metal) were carried out to clarify the effects of the depth of cut and the fiber directions on the surface finish, the chip formation and the cutting forces.3. Experimental analysis of micro machining process of single crystal copperOrthogonal micro machining process of single crystal copper was observed and analyzed aiming at clarifying the effects of the crystallographic orientation and the depth of cut on the chip formation, the cutting forces and the surface finish.4. Finite element analysis of machining process of single crystal copperA theoretical method based on a rigid-plastic FEM (Finite Element Method) was proposed, and the orthogonal micro machining process of single crystal copper was analyzed. The calculated results were in good agreement with the experimental results in the shapes of chips and the cutting forces.5. Discussion of micro machining processFollowing remarks are concluded in the research ;(1) Good surface finish is obtained in the machining experiments of FRM and copper when the depth of cut is decreased less than 1 mum.(2) Fiber directions and crystallographic orientations do not affect the chip formation process when the depth of cut is less than 1 mum.(3) Rigid-plastic FEM was successfully applied to the analysis of micro machining process of single crystal copper.