熱生長氧化物 TGO(Thermally Grown Oxide)生長和鈣鎂鋁矽酸鹽CMAS (Calcium-Magnesium-Aluminum-Silicate) 滲透是熱障塗層系統TBCs (Thermal Barrier Coating Systems) 中的兩種主要失效機制。需要注意的是，CMAS 在高溫下會迅速滲透到 TBCs 的孔隙中。在冷卻期間反應區周圍發生由相變引起的體積膨脹，當氧氣擴散到塗層中時會與鋁離子反應並生成氧化層，在高溫持續運行下氧化層變得越來越厚。在本篇研究，會先對比單一TC(Top-coat)層受CMAS侵蝕產生彎曲現象，彎曲高度的結果比對實驗與有限元素模擬的一致性，並將其參數匯入完整的塗層，並分析CMAS侵蝕與TGO生長合併前後對界面應力的影響。綜合效應的結果表明，在保溫階段CMAS侵蝕與TGO生長會造成不同方向的界面應力，導致CMAS侵蝕會抑制TGO生長的界面正向與剪應力，而在降溫階段相變化會抑制界面的剪應力然而會增加正向應力。因此，藉由此分析結果可以更全面了解CMAS侵蝕與TGO生長綜合影響機制。

Thermally grown oxide (TGO) growth and calcium magnesium aluminum silicate (CMAS) infiltration are the two major failure mechanisms in thermal barrier coating systems (TBCs). It should be noted that CMAS rapidly infiltrates through the pores of TBCs at high temperature. During the cooling time, volume expansion around the reaction region would occur owing to phase transformation. When oxygen diffuses into the coating, it reacts with aluminum ion and generates oxide layer. The oxide layer becomes thicker and thicker when coating system continually operates at high temperature. In this study, the result of the buckling height of free-standing attack by CMAS was used to demonstrate the consistency of the experiment and the finite element simulation. And then, this article investigates the combined effect of CMAS and TGO on the interface stress. The results show that CMAS infiltration and TGO growth will generate interfacial stress in opposite directions during the holding time, that is, CMAS infiltration will restrict the interfacial stress induced by TGO growth. The phase transformation will restrict the interfacial shear stress and enhance the interfacial normal stress between the TC and TGO interface during the cooling time. Therefore, this investigation can entirely demonstrate the combined effect of TGO and CMAS as well as predict the damage evolution along the interface.

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