Microstructural evolution at interfaces of thermal barrier coatings during isothermal oxidation
Microstructural evolution at interfaces of thermal barrier coatings during isothermal oxidation
复制标题
等温氧化过程中热障涂层界面微观结构的演变
DOI：
10.1016/j.jeurceramsoc.2016.02.011
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发表时间：
2016-06-01
影响因子：
5.7
通讯作者：
Ma, X. L.
中科院分区：
文献类型：
--
作者：
Liu, Y. Z.;Zheng, S. J.;Ma, X. L.
使用透射电子显微镜，我们调查的等离子喷涂热障涂层系统与氧化钇稳定的氧化锆顶涂层和NiCrAlY粘结涂层在1100摄氏度的等温氧化后，长达50小时的界面处的微观结构演变。有趣的是，热生长氧化物（TGO）层分裂成两个子层。原则上，两个亚层之一包括α-Al 2 O3、Cr 2 O3和Ni（Al，Cr）（2）O-4的混合物，而另一个由致密的α-Al 2 O3和Cr 2 O3组成。TGO层的主要显微组织演化遵循类似的顺序：原始相-> α-Al_2 O_3 + Cr_2 O_3-> α-Al_2 O_3 + Cr_2 O_3 + Ni（Al，Cr）（2）O_4。特别是，氧化50小时后，在顶部涂层-粘结层界面处的上部TGO亚层中形成γ-Ni和NiO，在粘结层-基底界面处的上部TGO亚层中形成γ-Ni和α-Cr。氧化50 h后，γ-Al和β-Ti在TGO-基体界面处析出。(C)2016爱思唯尔有限公司版权所有
Using transmission electron microscopy, we investigate microstructural evolution at interfaces of a plasma sprayed thermal barrier coating system with an yttria-stabilized zirconia top coat and a NiCrAlY bond coat after isothermal oxidation at 1100 degrees C for up to 50 h. Interestingly, thermally grown oxide (TGO) layers split into two sub-layers. In principle, one of the two sub-layers comprises a mixture of alpha-Al2O3, Cr2O3 and Ni(Al, Cr)(2)O-4, while the other one consists of dense alpha-Al2O3 and Cr2O3. Main microstructural evolution of the TGO layers follows a similar sequence that: original phases -> alpha-Al2O3 + Cr2O3 -> alpha-Al2O3 + Cr2O3 + Ni(Al, Cr)(2)O-4. Particularly, after 50 h oxidation, gamma-Ni and NiO form in the upper TGO sub-layer at the top coat-bond coat interface, and gamma-Ni and alpha-Cr form in the upper TGO sub-layer at the bond coat-substrate interface. Moreover, gamma-Al and beta-Ti precipitate at the TGO-substrate interface after 50 h oxidation. (C) 2016 Elsevier Ltd. All rights reserved.