Gadolinium zirconate/YSZ thermal barrier coatings: mixed-mode interfacial fracture toughness and sintering behavior.
Gadolinium zirconate/YSZ thermal barrier coatings: mixed-mode interfacial fracture toughness and sintering behavior.
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DOI：
10.1016/j.surfcoat.2015.12.012
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发表时间：
2016-01
影响因子：
5.4
通讯作者：
M. Frommherz;A. Scholz;M. Oechsner;Emine Bakan;R. Vaßen
中科院分区：
文献类型：
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作者：
M. Frommherz;A. Scholz;M. Oechsner;Emine Bakan;R. Vaßen
在这项工作中，详细研究了锆酸钆（GZO）/钇稳定氧化锆（YSZ）型现代双层热障涂层的分层韧性和烧结行为。这些特性主要决定应变耐受性，从而决定热障涂层 (TBC) 的性能。使用改进的四点弯曲装置测定分层韧性。结果表明，分层行为与传统的单层涂层显着不同，并且高度依赖于 GZO 层的特定微观结构。独立式 GZO 层的刚度和烧结行为是使用脉冲激励确定的，这是一种对陶瓷涂层整体刚度敏感的测试方法。因此，刚度的增加与微观结构的变化相关，特别是微裂纹的愈合以及层间裂纹和未熔化颗粒的烧结。结果表明，GZO 的特定喷射结构对烧结矿稳定性有很大影响，导致其具有特征温度依赖性。在这种情况下，在 1300 °C 以上的温度下，GZO 涂层与传统的 YSZ 涂层相比具有优势。
In this work, the delamination toughness and the sintering behavior of modern double-layer thermal barrier coatings of type gadolinium zirconate (GZO)/yttrium-stabilized zirconia (YSZ) are investigated in detail. These properties mainly determine the strain tolerance and thus the performance of thermal barrier coatings (TBCs). The delamination toughness was determined using a modified four-point bending setup. It is shown that the delamination behavior differs significantly from conventional monolayer coatings and is highly dependent on the specific microstructure of the GZO layer. The stiffness and sintering behavior of freestanding GZO layers were determined using impulse excitation, a test method sensitive to the global stiffness of the ceramic coating. The increase in stiffness is thereby correlated to microstructural changes, explicitly the healing of micro-cracks and the sintering of inter-lamellar cracks and unmolten particles. The results reveal that the specific spray structure of GZO has a great influence on the sinter stability which results in a characteristic temperature dependency. In this case the GZO coatings have an advantage in comparison to conventional YSZ coatings at temperatures above 1300 °C.