刀具切削刃钝圆对微细切削加工尺寸效应影响的有限元模拟研究

Finite Element Analysis of the Influence of Cutting Edge Radius on the Size Effect in Micro Cutting

为了研究刀具切削刃钝圆对微细切削加工尺寸效应的影响,运用商业有限元分析软件ABAQUS/Explicit,对考虑切削刃钝圆半径的二维正交切削加工过程进行了热力耦合有限元模拟,阐明了切削刃钝圆引起微细切削加工尺寸效应的内在原因。结果表明,切削刃钝圆是引起微细切削加工尺寸效应的原因之一。在小切深加工条件下,切削刃钝圆改变了有效前角的大小,增强了犁切效应;影响材料变形过程,扩展和拓宽了塑性剪切变形区的大小;增加了刀屑接触长度,引起了较高的能量损耗。

In order to investigate the influence of cutting edge radius on the size effect in micro cutting process, a coupled thermo-mechanical model with cutting edge radius considered is used to simulate the process of two-dimen- sional orthogonal machining using commercial finite element software ABAQUS/Explicit. Moreover, the intrinsic reason why the rounded cutting-edge causes size effect has been sufficiently clarified. The results indicate that the size effect in micro cutting is caused partially by the cutting edge radius, which affects the micro cutting process at smaller uncut chip thickness and thereby contributes to the size effect by altering the effective rake angle and enhancing the plowing effect, affecting the material deformation process, expanding and widening the plastic shear zone, and causing higher energy dissination due to increased tool-chip contact length.