Construction of virtual machining system for interrupted ultra-high speed machining

超高速加工作为一种先进加工系统的关键技术正逐渐走上舞台。为了发展该技术，正在尝试使用新设计的高切削速度机床进行试验研究。然而，对于机床、刀具的建造，在金钱和时间上需要花费巨大的费用，并且所选择的切削条件也有限。本研究尝试在数字计算机上构建螺旋铣刀切削过程仿真系统。在螺旋铣削加工中，不变形的切屑厚度随刀具旋转而变化，并以三维方式生成切屑。采用三维弹塑性有限元法开发了螺旋铣刀切削过程仿真系统。通过开发的系统，清晰地显示了刀具几何形状对切屑形成过程及其几何形状、切削力及其变化的影响。由于铣削过程是中断式的，因此在铣削过程中，冲击力的影响可以忽略不计。为了将系统扩展到超高速加工，通过对超高速颗粒与板材碰撞过程的仿真，讨论了系统的动态响应分析。在分析中，提出了一种基于粘弹塑性单元的材料力学性能模型。并根据实验数据提出了模型中材料常数的确定方法。

An ultra high speed machining is coming on a stage as the key technology for an advanced machining system. in order to develop the technology, the experimental researchs are trying using the newly designed machine tool with high cutting speed. However, for construction of the machine, tool the huge expense is reqiured on money and time, and the cutting condition to be selected is also limited.In this research the simulation system on cutting process by a helical milling cutter was tried to construct in a digital computer. In helical milling machining, undeformed chip thickness changes with cutter rotation, and a chip is generated in three dimensional manner. The simulation system on cutting process by helical milling cutter was developed using the three dimensional Elastic- Plastic Finite Element Method. Through the developed system the effects of tool geometry on chip formation process and its geometry and on cutting forces and its change were clearly shown.Since milling process has interrupted manner, the effect of impact force may be negligible in the process. In order to expand the system to ultra-high speed machining, the dynamic response analysis was discussed through simulation on collision process of an ultra-high speed particle against a plate. In the analysis a model of mechanical property of material was proposed with visco-elasto-plastic elements. And the method for determination of material constants in the model was proposed based on the experimental data.