Abstract The effect of thermal cycles on the microstructure and deuterium permeation of the Al2O3 coatings prepared by the MOD method was investigated. An as-deposited Al2O3 coating showed a uniform, smooth and dense surface morphology and was composed of γ-Al2O3 and α-Al2O3 phases. After 550 °C thermal cycles, all the Al2O3 coatings exhibited good phase stability. The Al2O3 coating remained intact and dense after 100 thermal cycles, while obvious cracks appeared on the coating surface after 150 thermal cycles. Furthermore, a deuterium permeation test of the as-deposited and thermally cycled Al2O3 coatings was carried out. The deuterium permeation flux of the Al2O3 coating increased with increasing the number of thermal cycles. The Al2O3 coatings with fewer than 100 thermal cycles remained dense and had a smooth surface morphology. However, several cracks appeared on the surface of the coating after 100 thermal cycles. In particular, delamination of the coating occurred after 150 thermal cycles. Disappearance of the (400) and (441) diffraction peaks of the γ-Al2O3 was observed after the deuterium permeation tests. The microscopic mechanism of the influence of thermal cycles on the microstructure and deuterium permeation of the Al2O3 coatings was analyzed.

中文翻译：

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热循环对MOD法制备的Al2O3涂层结构和氘渗透的影响

摘要 研究了热循环对MOD法制备的Al2O3涂层微观结构和氘渗透的影响。沉积态的 Al2O3 涂层显示出均匀、光滑和致密的表面形态，由 γ-Al2O3 和 α-Al2O3 相组成。在 550 °C 热循环后，所有的 Al2O3 涂层都表现出良好的相稳定性。Al2O3 涂层在 100 次热循环后保持完整和致密，而在 150 次热循环后涂层表面出现明显裂纹。此外，对沉积态和热循环的 Al2O3 涂层进行了氘渗透测试。Al2O3 涂层的氘渗透通量随着热循环次数的增加而增加。热循环少于 100 次的 Al2O3 涂层保持致密并具有光滑的表面形态。然而，100 次热循环后，涂层表面出现若干裂纹。特别是，涂层在 150 次热循环后发生分层。在氘渗透试验后观察到γ-Al2O3的(400)和(441)衍射峰消失。分析了热循环对Al2O3涂层微观结构和氘渗透影响的微观机制。