基于连续丝束剪切技术的变角度复合材料层合板的热屈曲分析

Thermal Buckling Analysis of VAT Composite Laminates Fabricated by Continuous Tow Shearing

连续丝束剪切(Continuous Tow Shearing, CTS)铺放技术是一种新的变角度层合板制作技术,这种新技术能显著减少丝束铺放过程中产生的丝束重叠和间隙等缺陷,然而,采用CTS技术铺设时,层合板的厚度将随着纤维角度的变化而变化.本文基于一阶剪切变形理论并应用Chebyshev-Ritz法对这种变厚度的变角度复合材料层合板的热屈曲问题进行了研究.假设纤维方向角沿板的长度方向按照线性变化,获得了均匀温度变化时变厚度层合板的临界热屈曲荷载.通过与现有文献的比较验证了本文方法的正确性,并进一步讨论了纤维铺设技术、纤维方向角的变化以及边界条件的不同对变角度复合材料层合板的临界屈曲温度的影响.研究结果表明,在体积相同的情况下,采用CTS铺设较传统的自动丝束铺放(AFP)可以进一步提升变角度层合板的临界屈曲温度.本文的研究结果可为变角度复合材料的设计提供一定的参考.

Continuous Tow Shearing(CTS) technology is a new manufacturing technology of Variable Angle Tow(VAT)composite laminates. This new technology can significantly reduce the defects of composite such as tow overlap and tow gap, and so on. However, the thickness of laminates will change with the variation of fiber angle when laying with CTS technology. Based on the first-order shear deformation theory and the Chebyshev-Ritz method, the thermal buckling of VAT composite laminates with variable thickness is studied in this paper. Assumed that the fibre angle of each ply varies linearly along the length of composite laminate, the critical thermal buckling load of VAT composite plate under uniform temperature rise is obtained. The correctness of this method is verified by comparing with the existing literature. The effects of fibre laying technology, fibre orientation angle and boundary conditions on the critical buckling temperature of VAT composite laminates are further discussed in numerical examples.The results show that the critical buckling temperature of VAT laminates fabricated by CTS can be further increased than those by AFP under the same volume. The results obtained here can provide a reference for the design of VAT composite laminates.