【作者】 成丽娟；

【导师】 李旭东；

【作者基本信息】 兰州理工大学 ， 材料学， 2004， 硕士

【摘要】 复合材料自出现至今，由于具有常规材料不可比拟的许多优异性能，已经在很多领域中得到了广泛的应用，其中，最显著的优点一其微观组织结构的可设计性，更使它成为材料科学研究的重点。在复合材料的各种性能中，有效刚度系数和热膨胀系数作为表征复合材料力学性能和物理性能的重要参数，对先进复合材料的设计与开发有着重要的影响作用，但目前在国内尚缺乏依据模拟的复合材料微观组织结构来预测材料性能这方面的研究工作，基于这一现状，本文在运用已开发的软件ProDesign的基础上，通过计算机模拟技术，模拟了复合材料的虚拟微观组织结构，预测了在机械一热载荷复合载荷作用下，各种复合材料模型材料的有效刚度系数和有效热膨胀系数，并运用数理统计的方法，探寻复合材料微观组织结构与其刚度系数、热膨胀系数之间有可能存在的、材料本身固有的内在联系。对有效刚度系数预测结果进行分析后发现：每种复合材料模型材料的刚度系数C11、 C12、 C44均随着增强相材料体积份额Vf的增大而增大，它们之间有很好的线性回归关系；此外，对于不同类型的复合材料模型材料，复合材料刚度系数与组分材料的刚度系数、弹性模量和各向异性比之间均有有规律的数值对应关系。但是基体材料的平均晶粒尺寸D对复合材料刚度系数的几乎没有影响。对有效热膨胀系数分析后得出：每种复合材料模型材料的热膨胀系数α11、 p22、 α33与Vf之间的对应关系不一致，而且没有一定的规律；此外，对于不同类型的复合材料模型材料，复合材料热膨胀系数与组分材料的热膨胀系数、刚度系数、各向异性比，复合材料模型材料的有效刚度系数和各向异性比之间具有规律性较强的数值对应关系。但是同刚度系数的分析结果一样，基体材料的平均晶粒尺寸D对复合材料热膨胀系数几乎没有影响．更多还原

【Abstract】 Since composite appearing, due to having many excellent properties comparing with other general materials, it has abroad application in many fields. Thereinto, the most distinct characteristic -designable, make composite become the emphasis in the research of material science. Within those properties, effective stiffness coefficient and effective thermal expansion coefficient as key parameters in representing mechanics and physics property of composite have considerable influence for advanced composite material design and development. At the present time, research on predicting composite property through simulated microstructures in domestic is lacked. Basing on this status, the paper employed developed software-ProDesign to simulating composite microstructures of short-fiber reinforced composite samples and predicting effective stiffness coefficient and thermal expansion coefficient of the samples. The samples are supposed to be subjected to coupled boundary traction due to mechanical loading and thermal cycling. By applying a regression analysis method, the relationship between composite microstructures and effective stiffness coefficient and thermal expansion coefficient is explored.Author has found that the stiffness coefficient C11, C12, C44 of each composite sample increase as the volume fraction Vf increases and there is a remarkable relationship between them. Besides, for different samples, there are a group of remarkable and quantified relationships between stiffness coefficient of composites and the elastic properties and anisotropy ratio of constituents. But the average grain size D has little effect on the stiffness coefficient of the composites.For effective thermal expansion coefficient, author has found that the relationship between the effective thermal expansion coefficient a11, 22 ,33 of each composite sample and volume fraction Vf is not identical. There isn’t remarkable relationship between them. But, for different samples, the same as the prediction of stiffness coefficient, there are a group of remarkable relationships between thermal expansion coefficient of composites and the thermal expansion coefficient, stiffness coefficient, anisotropy ratio of constituents. But the average grain size D also has little effect on the thermal expansion coefficient of the composites.更多还原