复合材料X型点阵夹芯结构力学性能研究

发布时间：2018-03-05 17:14

本文选题：复合材料　切入点：X型点阵夹芯结构　出处：《哈尔滨工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：复合材料点阵夹芯结构具有高比强/比刚度、阻尼减震等优点而广泛的用于各个领域,且其芯子中具有连续空间,为功能设计提供可能。本文提出了一种新型拓扑结构并研究了其力学性能。首先,采用水切割嵌锁组装制备复合材料X型点阵夹芯结构。接着,采用理论分析、数值模拟和试验测试的方法研究复合材料X型结构在平压载荷作用下的力学性能。简化X型结构模型,通过理论推出X型结构在平压载荷作用下的等效刚度及各种失效模式时的强度。采用试验的方法来研究不同相对密度的X型结构在平压载荷作用下的破坏机理及强度。根据X型结构的破坏机理提出增强方案并用试验的手段来研究这种增强型X型结构的力学性能。研究发现,复合材料X型结构在相对密度较低时,它的抗屈曲能力要优于金子塔点阵夹芯结构。然后,研究复合材料X型点阵在剪切载荷作用下的力学性能。简化复合材料X型结构在剪切载荷作用下的力学模型,推出X型结构的等效刚度和强度与加载方向的关系。采用试验的方法来研究不同相对密度的X型结构在剪切载荷作用下的破坏机理及强度。根据X型结构的破坏机理提出增强方案并用试验的手段来研究这种增强型X型结构的力学性能。研究发现,X型结构的等效刚度与加载方向无关,而剪切强度与加载方向有关。当载荷加载方向为0o时结构的剪切强度最小,当载荷加载方向为45o时剪切强度最大。最后,研究复合材料X型结构在侧压载荷作用下的力学性能。简化复合材料X型结构在侧压载荷作用下的力学模型,推导出其在侧压载荷作用下各种失效模式对应的强度。运用试验分析的方法对三种不同面板厚度的试件进行试验,试验中发现了面板皱曲的失效模式。研究发现,对于薄面板来说,X型结构抗节点间局部屈曲能力强于金字塔点阵夹芯结构。
[Abstract]:Composite lattice sandwich structures are widely used in various fields because of their advantages of high specific strength / specific stiffness, damping and damping, and their cores have continuous space. In this paper, a new topological structure is proposed and its mechanical properties are studied. Firstly, the composite X type lattice sandwich structure is fabricated by water cutting and interlocking assembly. Numerical simulation and test methods are used to study the mechanical properties of composite X-type structure under flat compression load. The equivalent stiffness and the strength of various failure modes of X-type structures under flat compression loading are deduced theoretically. The failure mechanism of X-type structures with different relative densities under flat compression loads is studied by means of experimental methods. Strength. According to the failure mechanism of X-type structure, the strengthening scheme is put forward and the mechanical properties of the enhanced X-type structure are studied by means of experiments. When the relative density of composite X type structure is low, its buckling ability is better than that of gold tower lattice sandwich structure. The mechanical properties of X type lattice matrix of composite materials under shear load are studied, and the mechanical model of X type composite structure under shear load is simplified. The relationship between the equivalent stiffness and strength of X-type structures and the direction of loading is deduced. The failure mechanism and strength of X-type structures with different relative densities under shear load are studied by means of tests. The mechanical properties of the enhanced X type structure are studied by means of experiments. It is found that the equivalent stiffness of the X type structure is independent of the loading direction. However, the shear strength is related to the loading direction. The shear strength of the structure is the lowest when the loading direction is 0 o, and the maximum when the loading direction is 45 o. Finally, The mechanical properties of composite X structure under lateral compression were studied, and the mechanical model of composite X structure under lateral compression was simplified. The corresponding strength of various failure modes under lateral pressure load is deduced. Three kinds of specimens with different face plate thickness are tested by the method of experimental analysis, and the failure modes of panel wrinkle are found in the test. For thin panel, the local buckling resistance of X type structure is better than that of pyramid lattice sandwich structure.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332

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