热障涂层失效行为及长寿命设计研究现状

Failure Behavior and Long-Life Design of Thermal Barrier Coating： A Review

摘要:

热障涂层可在航机/燃机热端部件表面起到隔热、保护基体的作用，在服役过程中除隔热性能外，服役寿命也是评价热障涂层性能的一个重要特征，影响热障涂层寿命的因素多且复杂．论文综述了导致热障涂层失效、影响涂层寿命的主要因素，包括粘结层表面热生长氧化物生长、陶瓷层高温热暴露后相变和烧结等，并进一步介绍了提高热障涂层寿命的涂层设计研究进展.从粘结层抗氧化、抗烧结陶瓷层、柱状结构陶瓷层、双陶瓷层四个方面，介绍了基于结构设计提高热障涂层寿命的方法．采用粘结层预氧化处理的方法提高粘结层的抗氧化性能，通过等隔热功能层级结构设计双陶瓷层结构涂层实现长寿命减厚设计，均有效地提高涂层的热循环寿命．

Abstract:

Thermal barrier coatings （TBCs） on the surface of the high-temperature part of aircraft/spacecraft mainly play a role of heat insulation and substrate protection. In addition to the thermal insulation performance， service life is another basic feature to evaluate the performance of TBCs during service. There are many and complex factors that affect the life of TBCs. In this paper， the main factors that lead to the failure of thermal barrier coatings and affect the life of the coating are reviewed， including the growth of thermally grown oxides on the surface of the bond coat， the phase transformation and the sintering of ceramics after high thermal exposure， etc.， and further introduced the research progress of coating design to improve the life of thermal barrier coatings. The research on long-life thermal barrier coatings based on structural design is introduced from four aspects： oxidation resistance of the bond coat， phase transformation and sintering resistance ceramic coat， columnar structure ceramic coat and double ceramic coat. The oxidation resistance of the bond coat was improved by the pre-oxidation treatment， and the double-ceramic layer can be designed by the hierarchical structure of isothermal insulation function， which can effectively prolong the thermal cycle life of the coating.