碳纤维复合材料振动辅助制孔有限元仿真建模研究

Finite Element Simulation Modeling of Vibration-Assisted Drilling CFRP

碳纤维复合材料广泛应用于航空航天、国防、医疗等领域,针对碳纤维复合材料制孔过程中出现的入口剥离、出口分层、撕裂与毛边等质量问题,结合振动辅助切削对制孔工艺进行改进。为了有效预测碳纤维复合材料振动辅助制孔工艺的效果,结合碳纤维复合材材料本构模型进行振动辅助制孔有限元仿真建模研究。借鉴已有的复合材料本构模型,构建了碳纤维复合材料力学模型;针对仿真碳纤维复合材料在制孔过程中的分层现象,提出了黏性层模型用于模拟复合材料层间损伤,并建立了有限元仿真模型;通过在刀具边界条件上施加振动模式,实现了振动辅助制孔的有限元仿真建模。将建立的有限元仿真模型的仿真结果与已有文献试验结果进行了比较,验证了所建的有限元仿真模型的正确性,并对比分析了普通钻削制孔与振动辅助钻削制孔的仿真结果。最后得出结论:采用振动辅助钻削碳纤维复合材料可以有效地降低轴向力,抑制毛刺和分层产生。

Carbon fiber reinforced plastic （CFRP） is widely used in the fields of aerospace, national defense and medical treatment. In the traditional process of drilling CFRP, there exist the problems of delamination at the entrance and exit, tearing and burrs. In the paper, the vibration assisted drilling process is used to improve the traditional process of drill- ing CFRP. In order to predict the effect of vibration assisted drilling of CFRP effectively, the modeling of finite element simulation of vibration assisted drilling is carried out by combining the constitutive model of CFRP. Firstly, the mechanical model of CFRP is established by considering the existing constitutive model while the cohesive element is used to simulate the interlayer damage. Then the influence of vibration is realized by applying the vibration movement to the boundary con- dition of cutting tool in the established model of finite element simulation. The finite element model is verified by compar- ing the simulation results with the experimental results. Finally, the simulation results of traditional drilling and vibration- assisted drilling are analyzed, which demonstrates that the latter one can effectively reduce the thrust force and suppress the burrs and delamination.