补片形状和尺寸对复合材料胶接修补的影响

Influence of Patch Shape and Size on Adhesively Bonded Composite Repair

与传统的机械修补技术相比,复合材料胶接修补具有结构增重小、可设计性强、成形简单和成本低等明显的优点。因此,复合材料胶接修补技术已成功地应用于一些军用和民用飞机的受损结构。借助于ANSYS软件,以三维逐渐损伤理论为依据,分别建立含不同形状补片的复合材料胶接修补模型,其中母板和补片采用正交各向异性损伤模型,胶层采用各向同性损伤模型。在单向拉伸载荷作用下,同时考虑层合板和胶层的损伤形式和扩展趋势,确定层合板的最终失效载荷,并与已有文献进行对比,验证模型的正确性。损伤模型计算结果表明,补片的形状和尺寸均是胶接修补的重要设计参数,其对层合板的最终失效载荷影响显著。斜放的方形补片的修补效果较佳,当对方形补片进行圆角化处理时,受损层合板的拉伸承载能力得到提高。

Compared with the traditional mechanical repair technology, the adhesively bonded repairs in composites have the obvious advantages of less increment of structure weight, strong design ability, easy forming and low cost. Therefore, the technology of adhesively bonded repairs in composites has been successfully applied to some damaged structures of military and civilian aircraft. Based on the three-dimensional progressive damage theory, the models of adhesively bonded repairs are respectively established with different shapes of the patches by using the software of ANSYS. Motherboard and patch are established with the orthogonal anisotropic damage model, and adhesive is established with the isotropic damage model. Under uniaxial tensile load, at the same time, considering the damage form and the trends of expansion of the laminates and adhesive, the ultimate failure load is determined. The validity of the method is proved by comparing with previous references. The calculation results of damage model show that the patch shape and size, which have a great effect on the ultimate failure load of composite laminates, are important design parameters of adhesively bonded repairs. The effect of repair with tilted square patch is better than others. When the round-corner process of tilted square patch is conducted, the load-bearing capacity of damaged laminates is improved.