功能梯度材料与结构湿热力耦合断裂行为的数值流形方法研究

项目名称： 功能梯度材料与结构湿热力耦合断裂行为的数值流形方法研究

项目编号： No.11462014

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 张慧华

作者单位： 南昌航空大学

项目金额： 56万元

中文摘要： 随着功能梯度材料(FGM)在航空航天、核工业、微电子、生物医学和纳米技术等领域的广泛应用，其在多场耦合作用下的断裂问题日益突出，探讨FGM的多场耦合断裂行为已成为当前研究的热点及难点问题。数值流形方法(NMM)因其特有的两套覆盖系统成为求解如断裂等不连续问题的强有力工具。本项目拟发展用于功能梯度材料与功能梯度涂层－基体结构(FGS)稳态及瞬态湿热力耦合断裂分析的NMM。首先建立可精确模拟含裂纹FGM与FGS中的湿度场和温度场的NMM，接着研究用于高精度提取FGM与FGS湿热力断裂参数的NMM，然后发展可高效高精度跟踪湿热力作用下裂纹准静态扩展路径的NMM，最后针对典型FGM与FGS，采用已发展的NMM深入探讨料梯度、裂纹几何特征、裂纹扩展准则、裂纹扩展步长和边界条件等因素对断裂参数和/或裂纹生长路径的影响，总结其中规律，为FGM与FGS的设计、修复和可靠性分析等提供理论依据和技术支持。

中文关键词： 功能梯度材料与结构；湿热力耦合断裂；数值流形方法；断裂参数；裂纹扩展

英文摘要： With the extensive application of functionally graded material (FGM) in the aerospace engineering, nuclear industry, microelectronic technology, biomedicine and nanotechnology, the fracture of FGMs subjected to multi-field coupling loadings is increasingly prominent. Presently, the study of multi-field coupling fracture behavior of FGMs is of hot spot and difficult point problem. Due to the unique use of two cover systems, the numerical manifold method (NMM) is proved to be a dominant computational tool for discontinuity problems (e.g., crack problems). In the present program, the NMM is developed and applied to solve fracture of FGM and functionally graded coating-substrate structure (FGS) under steady and transient hygro-thermo-mechanical loading. Firstly, the NMM for the accurate computation of humidity and temperature fields in the cracked FGM and FGS will be developed. Secondly, the NMM with high accuracy will be constructed to extract the fracture parameters under hygro-thermo-mechanical loading. Thirdly, the NMM for accurate and efficient capture of quasi-static crack growth path will be completed. Lastly, with the previously developed NMM, the effects of material gradients, crack geometries, crack propagation criteria, crack growth increment and boundary conditions on the fracture parameters and/or crack growth trajectory will be discussed in detail. The fracture behaviors summarized from the above investigations are expected to be helpful for the design, restoration and reliability analysis of FGM and FGS.

英文关键词： Functionally graded materials and structures;Hygro-thermo-mechanical fracture;Numerical manifold method;Fracture parameters;Crack growth