碳纳米管增强复合材料增强机理和损伤力学性能研究

With the exceptional physical and mechanical properties, and wide application prospects in industries, carbon nanotube reinforced composite has become a research hot topic in wide disciplines and continuing attracts increasing worldwide attention. However, the study on the reinforce mechanism and damage mechanical properties of carbon nanotube reinforced composites is still to be further expanded. By coupling the molecular dynamicis theory and meshless mehod, the multi-scale molecular dynamics meshless constitutive model of carbon nanotube reinforced composite materials is established firstly. Then the effective material properties are predicted, and the influence of the type and size of carbon nanotubes on the material properties and the reinforce mechanism is revealed. Through the improved meshless method, a multi-scale meshless computing model is proposed to analysis of delamination, and the effects of geometrical parameters, material parameters, boundary conditions, distribution types of carbon nanotube and lamination angle on the mechanical responses are investigated. The influence law of size and location of delamination will be studied. Finally, local effect, such as local buckling, caused by delamination will be examined from the practical engineering problems, and a damage location technique based on the multi-scale meshless method will be proposed to detect delamination of carbon nanotube reinforced composite laminated plates and shells.

碳纳米管增强复合材料因其独特的物理和力学性能及广阔的应用前景，近年来已迅速成为相关领域中最为活跃的研究课题。然而，关于碳纳米管增强复合材料增强机理和损伤力学性能研究还有待深入展开。结合分子动力学理论和无网格方法，本项目首先建立碳纳米管增强复合材料的多尺度分子动力学无网格本构模型，预测其有效材料属性参数，讨论碳纳米管类型和尺寸等因素对材料属性的影响，揭示碳纳米管增强复合材料的增强机理。通过改进的无网格方法，建立碳纳米管增强复合材料层合板壳结构分层损伤多尺度无网格计算模型，对含有分层损伤的碳纳米管增强复合材料层合板壳结构的力学性能进行模拟研究，讨论材料参数、几何参数、碳纳米管分布方式和方向和边界条件对其力学性能的影响，揭示分层损伤大小和位置对其力学性能的影响规律。最后，从实际工程问题出发探讨分层引起的局部屈曲等局部效应进行讨论，并对分层损伤的大小和位置进行多尺度数值检测分析。

纳米复合材料因其独特的物理和力学性能及广阔的应用前景，近年来已迅速成为相关领域中最为活跃的研究课题。纳米复合材料的力学性能决定了其工程应用前景。本项目采用理论和数值计算相结合的技术手段，建立了功能梯度纳米增强复合材料层合板、壳结构无网格计算模拟理论数值框架，研究功能梯度纳米复合材料层合板、壳结构的各种典型力学行为响应，分析几何参数、材料属性参数、边界条件、碳纳米管分布和铺设角度等对对纳米复合材料层合板、壳结构的弯曲，振动和屈曲等力学响应的影响规律。对含有基体损伤、裂纹和微观损伤的功能梯度纳米复合材料的力学行为进行相关研究，研究基体损伤、裂纹和微观损伤对纳米复合材料层合板、壳结构力学性能的相关影响规律。