一种基于FTS车削的微切削力模型

摘要

机械加工中的切削力模型建立对于研究工件表面形貌成型,探究切削理论有着深远的意义.在微切削加工领域,伺服车削通常用来加工自由曲面,但是考虑到尺寸效应,传统宏观领域的切削力模型无法真实地描述切削过程.针对微切削加工领域,提出了一种切削力模型,模型充分考虑了最小未成型切屑厚度,刀具切削刃钝圆以及工件对后刀面回弹引起的摩擦力.由于切削深度不同,所对应的切削原理也不同,将切削过程分为多个区域建模.当刀具切入工件后,随着切屑厚度的减小,切屑在前刀面分别经历宏观剪切、大负前角切削以及耕梨过程,而同时工件未切下的部分在后刀面的进一步作用下形成已加工表面,对应上述过程,将分为4个区域建模.最后,基于自主设计的能够精确测量两个方向切削力的快刀伺服装置(DFT-FTS)设计实验.%The establishment of cutting force model in machining is of great significance to study the surface morpholo-gy of workpiece and explore the cutting theory.Due to the so-called size effect,the cutting force model in the tradition-al field can not be directly applied to the micro-machining of free-form surface servo turning.In this paper, a cutting force prediction model for micro-cutting is proposed.The model gives full consideration to the factors such as the cut-ting edge of the cutting edge of the tool, the minimum unformed chip thickness and the frictional force generated by the flank return force. Due to the different cutting depth the cutting principle is different,the micro cutting force model will be developed according to different region. Finally, the experiment is designed based on the micro servo turning with self-designed a dual-axis force transducer-embedded fast tool servo (DFT-FTS) device.