基于渐进损伤理论的复合材料贴片修朴结构参数分析

发布时间：2018-05-08 04:16

本文选题：复合材料层合板 + 三维渐进损伤　；参考：《郑州大学》2015年硕士论文

【摘要】：先进复合材料因其优良的特性,诸如良好的比强度和比刚度、良好的耐腐蚀性能和良好的抗疲劳能力等,在航空航天工业中得到了广泛的应用。随着设计方法的不断完善和制造工艺的日益改善,复合材料的性能得到了大幅度提高,并在成本方面开始与传统的金属材料相竞争。鉴于此种情况,复合材料结构修理和损伤探测技术已成为复合材料技术研究的重要方向。本文主要研究了飞机复合材料贴片修补设计的分析方法。首先,本文建立了复合材料层合板渐进损伤分析的三维有限元模型。借助有限元软件ANSYS的二次开发语言(APDL),编写三维Hashin准则作为失效判断准则,分别考虑了基体开裂、基体纤维剪切、分层和纤维断裂四种单元破坏形式,退化准则采用固定的材料刚度折减系数。有限元计算结果与试验数据相吻合,验证了本文建立的复合材料三维渐进损伤模型的有效性。其次,本文分别建立了基于连续介质损伤力学和最大剪应力理论的胶层有限元模型。假设胶层含各向同性损伤,分别采用两种胶层模型进行有分析计算,通过比较计算结果和试验数据的吻合程度,确定两种模型均有较高的可靠性,本文采用胶层基于连续介质损伤力学的贴片修补模型。第三,分析了复合材料贴片修理模型在均布拉伸载荷下的应力分布情况,总结得到贴片修补模型的高应力集中区域。第四,建立基于三维渐进损伤理论的复合材料贴片修补模型,分析了补片半径不同时模型的极限载荷和失效扩展情况,总结得到三种贴片修补结构的整体失效模式,并分析其产生的原因。同时,分析了补片厚度、补片形状和补片材料对模型修补效果的影响,确定修补效率最高的补片厚度、补片形状及补片材料等参数。最后,考虑胶层的参数(胶层厚度、胶粘剂种类)对贴片修补模型极限载荷和失效扩展情况的影响,确定修补效果最佳的胶层参数。
[Abstract]:Advanced composite materials have been widely used in aerospace industry because of their excellent properties, such as good specific strength and stiffness, good corrosion resistance and fatigue resistance. With the continuous improvement of design method and manufacturing process, the properties of composite materials have been greatly improved, and the cost of the composites has begun to compete with the traditional metal materials. In view of this situation, composite structure repair and damage detection technology has become an important research direction of composite technology. This paper mainly studies the analysis method of aircraft composite patch repair design. Firstly, a three-dimensional finite element model for progressive damage analysis of composite laminated plates is established. With the help of the secondary development language of finite element software ANSYS, three dimensional Hashin criterion is compiled as the failure judgment criterion. The failure modes of matrix cracking, matrix fiber shear, delamination and fiber fracture are considered, respectively. The degradation criterion adopts a fixed material stiffness reduction coefficient. The results of finite element method are in agreement with the experimental data, which verifies the validity of the 3D progressive damage model of composite materials established in this paper. Secondly, the finite element model of rubber layer based on the theory of continuum damage mechanics and maximum shear stress is established in this paper. Assuming that the rubber layer contains isotropic damage, two kinds of rubber layer models are used to carry out the analysis and calculation respectively. By comparing the calculated results with the experimental data, it is determined that the two models have high reliability. In this paper, a patch repair model based on continuum damage mechanics is used. Thirdly, the stress distribution of the composite patch repair model under uniform tensile load is analyzed, and the high stress concentration region of the patch repair model is obtained. Fourthly, a composite patch repair model based on 3D progressive damage theory is established, and the ultimate load and failure expansion of the model with different radius are analyzed, and the overall failure modes of three kinds of patch repair structures are summarized. The causes of its occurrence are analyzed. At the same time, the effects of patch thickness, patch shape and patch material on the effect of model repair were analyzed, and the parameters such as patch thickness, patch shape and patch material, which had the highest repair efficiency, were determined. Finally, considering the influence of the rubber layer parameters (thickness of adhesive layer, adhesive type) on the ultimate load and failure expansion of the patch repair model, the parameters of the best repair effect are determined.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33

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