摘要:根据典型的热障涂层结构,在有限元仿真软件ABAQUS中建立具有热障涂层结构的有限元模型,此模型考虑了陶瓷层中含有一定孔隙度的陶瓷的情况,利用此模型研究了陶瓷层有无孔隙对热障涂层竖向应力S22的影响,讨论了陶瓷层与氧化层界面处的竖向应力S22沿着界面的变化规律,由此来判断陶瓷层的可能失效位置。具体从有无孔隙,孔隙的直径不同,陶瓷孔隙度不同以及孔边的最小距离不同等多个方面来研究对均匀温度场下的竖向应力S22的影响。结果表明,孔隙的直径大小,陶瓷孔隙度和孔边的最小距离都影响竖向应力S22的分布,导致了界面层出现了不同的受力情况。并且得到了以下的结论:1,陶瓷层中孔隙周边会存在应力集中现象,在陶瓷层与氧化层之间的界面附近,陶瓷层内的孔隙会对沿界面的竖向应力S22有一定的影响。2,孔隙度相同的情况下,孔隙越大会导致孔隙越多,对竖向应力S22的影响更大。3,孔隙不同的情况下,孔隙度较大的竖向应力S22所受的影响更大。4,孔隙大小随机以及孔边最小距离的影响,孔边最小距离越大,界面附近陶瓷层的竖向应力S22的整体波动性越大。
关键字:热障涂层;陶瓷层的孔隙;有限元方法;竖向应力S22
Abstract:According to the typical thermal barrier coating structure, the finite element model of thermal barrier thermal barrier coating structure is established in finite element analysis software ABAQUS. This model considers the porosity of the ceramic layer with a certain porosity, and the effect of the porosity of the ceramic layer on the vertical stress S22 of the thermal barrier coating is studied by this model. The variation of the vertical stress S22 at the interface between the ceramic layer and the oxide layer is discussed, and the possible failure position of the ceramic layer is determined. The influence of the vertical stress S22 on the uniform temperature field is studied from the aspects of the presence or absence of porosity, different diameter of porosity, different porosity of ceramic and the minimum distance of hole edge. The results show that the diameter of the pore, the porosity of the ceramic and the minimum distance of the hole edge all affect the distribution of the vertical stress S22, resulting in different stress in the interface layer. And got the following conclusions: 1, there will be stress concentration in the periphery of the pores in the ceramic layer. In the vicinity of the interface between the ceramic layer and the oxide layer, the pores in the ceramic layer will have some influence on the vertical stress S22 along the interface.2, the same porosity of the case, the larger the pores will lead to more porous, the impact of vertical stress S22 greater.3, the pores of different circumstances, the greater the porosity of the vertical stress S22 suffered greater impact.4, the pore size is random and the minimum distance of the hole edge, the maximum distance of the hole edge, the interface near the ceramic layer vertical stress S22 the greater the overall volatility.
Keywords: Thermal barrier coating ; The porosity of the ceramic layer; Finite element method; Vertical stress S22
目 录
第一章绪论 1
1.1研究背景 1
1.2热障涂层的基本模型结构 1
1.3热障涂层的历史以及现状 2
1.4热障涂层的未来发展 5
1.5有限元理论 5
1.5.1有限元的发展史、现状与展望 5
1.5.2有限元理论