复合材料单向板刚度退化及数值仿真分析研究

发布时间：2018-01-05 22:36

本文关键词：复合材料单向板刚度退化及数值仿真分析研究　出处：《南京航空航天大学》2016年硕士论文　论文类型：学位论文

【摘要】：在航空领域,随着复合材料在飞机主承力结构中的应用,其愈加复杂的受载情况和不断提高的承载水平使复合材料的疲劳问题变得不可避免。复合材料在疲劳载荷作用下其损伤机理十分复杂,给复合材料疲劳失效分析和寿命预测带来了严峻的挑战。刚度性能持续退化是复合材料宏观力学性能疲劳变化的重要体现,因此基于复合材料疲劳损伤机理对刚度疲劳退化进行系统研究具有重要的意义和价值。本文主要研究复合材料单向板在静力拉伸载荷作用下的刚度退化规律及在疲劳载荷作用下的剪切模量退化规律。论文首先介绍对复合材料疲劳破坏机理的认识,并总结现有的复合材料疲劳分析模型,重点介绍剩余刚度模型和数值仿真分析模型;其次对一系列不同铺角的碳纤维复合材料单向板进行了大量疲劳试验;随后先从复合材料静力破坏模式入手,分析影响材料弹性模量退化的各种因素,并重点研究载荷和铺设角度的影响,构建了复合材料刚度静力退化模型,基于该模型进行单向板静强度数值仿真分析;再从单向板疲劳破坏模式入手,研究载荷和铺设角度对剪切模量疲劳退化的影响,构建复合材料剪切模量疲劳退化模型,基于该模型进行单向板疲劳数值仿真分析。对比分析表明数值仿真结果与试验结果较为吻合,论文所构建的刚度静力退化模型和剪切模量疲劳退化模型较合理地描述了相应的复合材料刚度的退化规律。
[Abstract]:In the field of aviation, with the application of composite materials in aircraft main bearing structure, the more complex the load and improve the carrying capacity of the fatigue problem of composites becomes inevitable. Composite materials in the fatigue damage mechanism is very complex, for composite fatigue failure analysis and life prediction brought serious the challenge. The stiffness performance degradation is an important manifestation of the macro mechanical properties of composite materials fatigue changes, so the stiffness degradation fatigue fatigue damage mechanism of composite materials based on the significance and value of system research. This paper mainly studies the unidirectional composites under tensile load in the action of static stiffness degradation law and shear modulus in under fatigue load degradation. This thesis first introduces the knowledge of composite fatigue failure mechanism, and summarizes the existing composite materials The analysis focuses on the material fatigue model, residual stiffness model and numerical simulation model; a second fatigue test on a series of different laying angle of unidirectional laminates; then from static modes of failure of composite material, analysis of various factors affecting the material elastic modulus degradation, and focuses on the effects of load and laying angle, constructs the composite static stiffness degradation model, based on the model for numerical simulation of static strength analysis of one-way slab; from one-way slab fatigue failure mode, effects of load and ply angle on the degradation of shear modulus, fatigue, fatigue design of composite shear modulus degradation model, numerical simulation analysis of fatigue of unidirectional plate based on this model. Comparative analysis shows that the numerical simulation results and the experimental results are consistent, the static stiffness degradation model and shear modulus The fatigue degradation model is a more reasonable description of the degradation law of the corresponding composite stiffness.

【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：V250.2

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