碳纤维/环氧树脂复合材料钻削温度场建模与试验

碳纤维/ 环氧树脂(C/ E)复合材料具有轻质、高模量、高比强度等优良特性在航空航天等领域有广泛的应用,但由于其各向异性、层间强度低、导热系数小和树脂对温度敏感等特点,导致钻孔加工中热量很容易聚集,形成很高的温度梯度,极易产生分层、毛刺等缺陷。以C/ E 复合材料钻孔过程中温度场的分布及变化为研究对象,依据传热学的基本原理,采用有限差分法(FDM),建立了C/ E 复合材料钻削温度场模型,探讨切削温度沿纤维方向的分布规律。采用硬质合金钻头开展C/ E 复合材料钻孔测温试验,采用预埋热电偶方法测量纤维方向不同处的温升,采用红外测温的方法测量出口处温度场分布。通过对试验结果和模型仿真结果对比分析可知:温度场仿真模型有较高的准确性,出口处温度场分布呈椭圆形,平行纤维方向时温升较高。

Modeling and Experimental Research on Drilling Temperature Field of Carbon Fiber/Epoxy Reinforced Composites

Carbon fiber/ epoxy (C/ E) composites are characterized by light weight, high modulus and high specific strength, which make their use especially attractive to aerospace applications. But heat is easy to aggregate during drilling of C/ E composites because of their anisotropy, low interlayer strength and the low thermal conductivity. It can result in a high temperature gradient which has a significant effect on the quality of the workpiece and the tool wear. A drilling temperature field model of the unidirectional composites is developed. Based on the finite difference method (FDM), the temperature distribution and changes are simulated. A carbide twist drill is used in the experiments. The rise in temperature rise at different fiber directions and distribution of temperature field at the exit are measured by using thermocouples and infrared camera, respectively. The results show that the temperature distribution is in agreement with the temperature field model, the distribution of temperature field at the exit oval, and the in temperature rise is higher in parallel with the fiber direction.