Mechanistic Understanding for Degraded Thermal Barrier Coatings
Mechanistic Understanding for Degraded Thermal Barrier Coatings
复制标题
热障涂层退化的机理理解
DOI：
10.1299/jsmea.44.507
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
T. Torigoe
中科院分区：
文献类型：
--
作者：
K. Ogawa;T. Shoji;Hisahiko Aoki;N. Fujita;T. Torigoe
采用等离子喷涂技术在镍基高温合金基体上制备了双层热障涂层。涂层由MCrAlY粘结涂层的内层和8wt%氧化钇稳定的氧化锆（YSZ）热障涂层（TBC）的外层组成。时效后，在YSZ和MCrAlY之间的界面处观察到热生长氧化物（TGO）层。TGO层在SEM图像中具有两个不同的对比层。黑色的更接近MCrAlY，灰色的更接近YSZ。两层的厚度均随着老化而增加。在灰层处还观察到大量的孔隙和YSZ处的微裂纹。大部分裂纹是通过孔隙扩展的。从这一点来看，可以说宏观裂纹形成的机制是附着力的恶化，伴随着孔隙或微裂纹数量的增加。
A two-layer plasma sprayed thermal barrier coating on Ni base superalloy substrate was characterized. The coating was comprised of an inner layer of MCrAIY bond coating and an outer layer of 8 wt% yttria stabilized zirconia (YSZ) thermal barrier coating (TBC). After aging, the thermally grown oxide (TGO) layer at interface between YSZ and MCrAlY was observed. The TGO layer had two different contrast layers in the SEM images. The black one was closer to MCrAlY and the gray one was closer to YSZ. The thickness of both layers increased with aging. Countless porosities at the gray layer and microcrack at YSZ were also observed. Most of the macrocrack grew through the porosities. From this point of view one may say that the mechanism of macrocrack formation is a deterioration of adhesion accompanied by an increase of number of the porosities or the microcrack.