项目名称: 纳米隔热材料力学性能的尺度研究与实验验证
项目编号: No.11272030
项目类型: 面上项目
立项/批准年度: 2013
项目学科: 数理科学和化学
项目作者: 卢子兴
作者单位: 北京航空航天大学
项目金额: 86万元
中文摘要: 二氧化硅气凝胶作为新型的超级纳米隔热材料在航空、航天领域具有重要的应用前景,但是较差的力学性能制约了其发展和应用。因此,如何提高其力学性能成为该类材料研究所面临的一个重要挑战。本项目拟以陶瓷纤维增强二氧化硅气凝胶复合材料为研究对象,根据该类材料内在结构多尺度的特点,拟结合实验与数值模拟方法针对其力学行为开展较为系统的研究。通过扫描电镜等先进设备观察材料内部的多尺度结构,并进行系统的力学性能测试,以获取该类材料在不同载荷下的力学性能和变形机制。此外,结合分子动力学、离散元和有限元法,发展一种适用于纤维增强气凝胶复合材料的多尺度力学模型,即:在不同尺度上分别建立相应的力学模型,通过控制方程建立不同尺度模拟方法之间的关联,最终形成一套适用于研究具有典型多尺度结构复合材料力学行为的数值模拟方法。并结合实验和数值模拟结果,建立工程适用的失效判据,为材料性能的优化设计奠定理论基础。
中文关键词: 陶瓷纤维增强二氧化硅气凝胶复合材料;多尺度力学模型;力学性能;变形机制;
英文摘要: As an emerging super-nano-insulating materials, silica dioxide aerogels have important applications in the aerospace field, but the poor mechanical properties limit the development and application of this material.Therefore, improvement of its mechanical properties becomes an important challenge. Taking the ceramic fiber reinforced silica dioxide aerogel composites as the object and considering the interior multiscale structures, this project is planned to investigate the mechanical behaivors sysmetically, with combining the experiments and numerical simulation. Firstly, the typical mechanical tests on the material is carried out and the multiscale structures in the material are characterized by using scanned electron microscope (SEM), obtaining the mechanical properties and deformation mechanism of this material. In addition, bridging the molecular dynamics (MD) simulation, discrete element method (DEM) and finite element method (FEM),a multiscale mechanical model is developed for the fiber reinforced aerogel material and a numerical simulation method is obtained, i.e. building corresponding mechanical model at different scales, and connecting the simulation methods by certain controlling equations, and a method is obtained which is suitable for research on the mechanical behaviors of composites with typical m
英文关键词: Fiber-reinforced silica aerogel composites;Multi-scale mechanical model;Mechanical properties;Deformation mechanism;