热障涂层中热生长氧化层应力及变形研究进展

Progress in Research on Stress and Distortion of Thermally Grown Oxides in TBCs

从影响热生长氧化层(TGO)变形的因素、计算模型和计算方法方面综述国内外学者近年来在热生长氧化层变形和应力方面的研究成果。详细评述热膨胀失配、蠕变、TGO生长、黏结层相变和界面形貌等因素对TGO变形和应力的影响,并介绍目前研究TGO变形和应力的主要方法和计算模型。提出:基于内聚力模型(CZM)的扩展有限元方法(X-FEM)、(扩展)Voronoi有限元模型可以解决基于传统有限元方法和断裂力学方法在研究TGO裂纹扩展问题、获取TGO临界断裂参数等方面存在的困难,是一种有前途的研究TGO变形、应力及裂纹问题的方法。

Progress in research on the stress and distortion of thermally grown oxides（TGO） was reviewed.The factors affecting the stress and distortion of TGO such as thermal expansion mismatch,creep of bond coat and TGO,growth of TGO,phase transformations of bond coat,interfacial morphology were evaluated.The research method and calculation model including analytical models and finite element models were introduced.In traditional FEM model,the fracture criterion of the TGO is hard to measure,and can＇t deal with the problem of interaction and growth of multiple cracks.The extended finite element method （X-FEM） coupled with cohesive zone model （CZM） and the Voronoi element model overcomes these shortfalls and shows advantage in simulation of crack problems in TGO without needing of re-meshing and some critical crack parameters which remain experimentally elusive.It will be an effective method in TGO stress,distortion and crack problem.