基于内聚力行为的复合材料L型胶接接头分层扩展研究

Study on delamination damage evolution of composite L-shaped adhesive joint based on cohesive behavior

复合材料胶接接头是飞机结构中常用的典型结构之一,分层损伤是复合材料胶接结构最重要的损伤形式。以L型胶接接头为研究对象,开展静力和疲劳试验,分析其静力和疲劳分层的扩展规律与失效模式。基于内聚力本构关系,发展了复合材料静力和高周疲劳分层本构模型。采用有限元软件建立了复合材料L型胶接接头的静力和疲劳数值模型,对其应力分布、变形模式和分层扩展规律进行系统研究,数值结果和试验结果吻合良好。结合试验和数值计算方法,共同揭示L型胶接接头在静态和疲劳载荷作用下的分层起始、扩展和失效机理,为复合材料胶接结构的强度和疲劳寿命分析提供理论和工程指导。

The adhesive joint of composite materials is one of the typical structures in aircraft structures, and the delamination damage is one of the most important damage modes in composite adhesive joints. In this paper, static and fatigue tests were carried out on L-shaped adhesive joints to analyze the damage evolution and failure modes of delamination damage under static and fatigue loadings. Based on the cohesive constitutive models, the static and high-cycle fatigue delamination constitutive models were developed. The static and fatigue numerical models of composite L-shaped adhesive joints were established by using finite element software. The stress distribution, deformation modes and delamination propagation laws were systematically studied. The simulation results are in good agreement with the experimental results. The delamination damage initiation, evolution and failure mechanism of L-shaped adhesive joints under static and fatigue loads were revealed by combining the experimental and the numerical results, which will provide theoretical and engineering guidance for strength and fatigue analysis of composite adhesive structures.