Hot corrosion evaluation of Gd₂O₃-Yb₂O₃ co-doped Y₂O₃ stabilized ZrO₂ thermal barrier oxides exposed to Na₂SO₄+V₂O₅ molten salt

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• 作者：Lei Guo^a ; ^b ; ^c ; ^{glei028@tju.edu.cn} ; Chenglong Zhang^a ; ^b ; Mingzhu Li^a ; ^b ; Wei Sun^a ; Zhaoyang Zhang^a ; Fuxing Ye^a ; ^b ; ^c
• 关键词：Thermal barrier coatings (TBCs) ; Doped YSZ ; Hot corrosion ; Molten salt
• 刊名：Ceramics International
• 出版年：2017
• 出版时间：1 February 2017
• 年：2017
• 卷：43
• 期：2
• 页码：2780-2785
• 全文大小：2648 K
• 卷排序：43

文摘

1 mol% Gd2O3 and 1 mol% Yb2O3 co-doped 3.5 mol% Y2O3 stabilized ZrO2 (GdYb-YSZ) ceramics in metastable tetragonal (t′) structure were fabricated, and their hot corrosion behaviors were evaluated. The corrosion tests were performed at 700 °C, 800 °C, 900 °C and 1000 °C for 4 h in the presence of Na2SO4+V2O5 molten salt. After corrosion, t′ phase could still be detected on the corroded surfaces and its content decreased with increasing the corrosion temperature. The corrosion products were composed of doped YVO4 and m-ZrO2, but some amounts of Na4V2O7 were found at low corrosion temperatures (700 °C and 800 °C). The corrosion resistance characteristic of GdYb-YSZ was compared with that of YSZ. Under an identical corrosion condition, GdYb-YSZ had less monoclinic phase formed, indicative of a better hot corrosion resistance. The hot corrosion mechanism was discussed in detail.