CFRP高速铣削渐进损伤切削力模型研究

Research of Cutting Force Model for Progressive Damage in High Speed Milling of CFRP

基于VUMAT子程序编写三维Hashin失效准则、材料刚度退化,采用Abaqus/Explicit建立求解CFRP高速铣削渐进损伤切削力模型,并通过相同实验参数进行验证,分析了纤维方向对铣削过程中切削力、应力以及材料失效的影响机制。结果表明,CFRP高速铣削切削力实验值与仿真值误差小于5%,说明渐进损伤模型可靠性较高;纤维方向对切削过程中切削力和应力有显著影响,切削力与应力都遵循规律:45°>90°>0>135°,不同角度切削力与应力差异主要是由纤维强度各向异性以及纤维受到刀尖不同类型作用力导致的。此外,切削过程中材料损伤是渐进发生的,纤维角度对材料失效也有重要影响,其中45°方向纤维失效规模最大,135°方向纤维失效规模最小。

3D Hashin failure criterion and material stiffness degradation are compiled via VUMAT subroutine.A finite element model for solving progressive damage cutting force in high-speed milling of CFRP is established via Abaqus.The experimental parameters are used to verify the model.The influence mechanism of the fiber direction on the cutting force,stress and material failure in milling process is analyzed.The results show that the error of cutting force between the CFRP high speed milling experiment and the simulation value is below 5%,which indicates that the reliability of the present model is high.Fiber direction has a significant influence on the cutting force and stress in cutting process.Cutting force and stress follow the rule:45°>90°>0>135°.The difference among the cutting force and stress in different angles is mainly caused by the anisotropy of the fiber strength and different types of force acting between the fibers and the tool tip.In addition,the material damage occurs gradually in the cutting process.Fiber angle also has an important impact on the material fracture,the largest fracture scale is of 45°and the smallest is of 135°.