权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

A Study of Crack Propagation Paths in Functionally Graded Material Plates

功能梯度材料板裂纹扩展路径的研究

基本信息

批准号：
10650080
负责人：
NODA Naotake
金额：
$ 2.05万
依托单位：
Shizuoka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650080/
关键词：
Crack propagation paths Thermal stresses Functionally gradient material plates Fracture mechanics stress intensity factor Finite element method Unsteady state Cracks 弾性熱衝撃き裂伝播亀裂伝播

项目摘要

This research project consists of two parts : [1] Study of thermal stress intensity factors in the functionally graded material plates (FGPs) with cracks under thermal load, [2] A study of crack propagation paths in FGPs under thermal load by Finite Element Methods (FEM).PART [1] : Study of constitutional equations of the functionally graded materials (FGMs) under thermal loading.(1) We proposed a laminated composite model to study FGMs with arbitrary compositional profile subjected to thermal loading.(2) Multiple crack problems could be treated by the proposed a laminated composite model.(3) When FGPs with collinear crack are subjected thermal loading, stress intensity factor at an inner edge of collinear crack is larger than one at outer edge and increases with decreasing the distance of each crack.PART [2] : A study of crack propagation paths in FGPs under thermal load by Finite Element Methods (FEM).(1) We could develop a program with automatically production of mesh of FEM.(2) For the single crack growth simulation, the straight or curved cracks are obtained for several conditions of the thermal shock and the compositional profiles. Some cracks curve sharply and grow in the direction parallel to the surface. Such cracks cause delamination of the surface. The other cracks are arrested in the middle of the plate.(3) As two crack growths is one of the basic forms of the multiple thermal cracking, the interaction between the two cracks are discussed. The cracks grow in curve and away from each other, when the cracks exist in short distance. For spalling cracks that come close to each other from a long distance, the cracks curve in the direction normal to the surface as the crack tips come closer. Then the cracks are arrested in the middle of the plate.

本课题包括两个部分：[1]热载荷作用下含裂纹功能梯度材料板的热应力强度因子研究；[2]热载荷作用下功能梯度材料板裂纹扩展路径的有限元研究。[1]部分：热载荷作用下功能梯度材料（fgm）的本构方程研究。(1)提出了一种层合复合材料模型，用于研究任意组分的fgm在热载荷作用下的性能。(2)所提出的层合复合材料模型可以处理多重裂纹问题。(3)含共线裂纹的FGPs受热载荷时，共线裂纹内缘应力强度因子大于外缘应力强度因子，且随各裂纹距离的减小而增大。[2]：热载荷作用下fgp裂纹扩展路径的有限元研究。(1)开发了有限元网格自动生成程序。(2)对于单裂纹扩展模拟，在不同的热冲击和成分分布条件下，得到了直线裂纹和弯曲裂纹。有些裂纹曲线陡峭，沿平行于表面的方向扩展。这种裂缝引起表面分层。其他的裂缝被控制在板块的中间。(3)由于双裂纹扩展是多重热裂纹的基本形式之一，因此讨论了双裂纹扩展之间的相互作用。当裂纹存在距离较近时，裂纹呈曲线状扩展且彼此远离。对于距离较近的剥落裂纹，裂纹尖端越靠近，裂纹沿垂直于表面的方向弯曲。然后，裂缝被控制在板块的中间。