基于正交切削模拟的直齿圆柱铣刀前角优化

Milling tool normal rake angle optimization based on orthogonal cutting simulation

为了优化设计直齿圆柱铣刀前角以延长刀具使用寿命,建立了金属切削加工的平面应变有限元模型.该有限元模型基于切削加工的热弹塑性有限元方程和力学边界条件的简化,综合了切屑的几何和物理分离标准,利用修正的库仑摩擦定律定义了刀屑间的摩擦.模拟了不同刀具前角和不同切削速度条件下的切削加工过程.结果分析表明,在相同材料去除率情况下,刀具前角越大,刀具前刀面上的切削温度越低,刀具具有较长的使用寿命.通过优化刀具前角,提高切削速度,切削力和切削温度变化较小,但是显著提高了材料去除率.

To optimize the normal rake angle of milling tool with straight cutting edges and to lengthen tool life, a plane-strain finite element model (FEM) of metal machining was established. On the basis of the thermo-elastic-plastic finite element equation and simplification of metal cutting mechanics, FEM integrated geometrical and physical criteria of chip separation, and the revised Coulomb friction law were used to define the interface friction of tool and chip. Machining conditions of different normal rake angles and machining speeds were simulated by using this FEM. Analysis results of cutting temperature and forces show that under conditions of the same material removal rate and larger rake angle, the tool has lower machining temperature on the rake face and longer life. With the optimized normal rake angle, machining force and temperature change less, but material removal rate is improved obviously with increasing cutting speed.