复合材料胶接接头强度设计研究

摘要

Adhesive bonding is one of the main forms of the aircraft composite structure.The failure modes of composite adhesive joint are complex,including composite laminates failure and adhesive failure,it is difficult to simulation various damage modes and the influence between them.An analytical method is proposed which integrated two failure models,the cohesive zone model used for simulating the composite adhesive,and the Hashin three-dimensional failure criterion used for simulating the composite laminates failure.An analysis model was established for the composite laminates bonding structure,which can simulate adhesive failure and composite panel failure as while.By using this model,the bonding strength of composite panel was predicted accurately.The influences of lap length,drop off zone slope and drop off style of the lap on joint strength were studied,and the influence law was obtained.%胶接是飞机复合材料结构的主要连接形式之一.由于复合材料胶接失效模式复杂,包含有复合材料层合板失效和胶层失效,强度预测的难点在于仿真各种损伤模式及其相互之间的影响.因此,提出一种集成了两种失效模型的分析方法,其中基于三维Hashin失效准则和指数型刚度退化准则的失效模型仿真复合材料层合板失效,内聚力模型仿真胶层失效.建立了能够同时模拟复合材料层合板失效和胶层失效的复合材料胶接强度分析模型.利用该模型对复合材料胶接接头强度进行了计算,计算结果与试验结果一致性较好.运用所建立的分析模型,研究了复合材料胶接接头的主要设计参数(搭接长度、贴边末端厚度过渡区阶梯比、贴片末端铺层丢层方式等)对接头强度的影响,得到了设计参数对胶接接头强度影响的规律.