The 0.1Al₂O₃-ZrO₂ reinforced MoSi₂ composite coating was prepared on pure Mo substrate to improve its high-temperature oxidation resistance, of which the MoSi₂ coating was prepared by a modified pack siliconizing process and subsequently the 0.1Al₂O₃-ZrO₂ layer was generated on the as-prepared MoSi₂ layer by a non-hydrolytic sol-gel method. The phase composition and microstructure of the as-prepared composite coating before and after oxidation exposure were investigated by XRD, SEM and EDS. Different from the loose structure of the single MoSi₂ coating after oxidation exposure, the 0.1Al₂O₃-ZrO₂ reinforced MoSi₂ composite coating exhibited a relatively compact internal structure with less through-thickness cracks. The introduction of 0.1Al₂O₃-ZrO₂ layer effectively prevented the cracking and spalling of the glassy SiO₂ scale formed on the surface of MoSi₂ during the oxidation, and then the SiO₂ scale could be well stabilized on the coating surface. The protective SiO₂ glassy scale embedded with stable ZrO₂ and ZrSiO₄ phase was formed, contributing to the improvement in the structure stability of the composite coating. It was proposed that ZrO₂, ZrSiO₄ and SiO₂ developed a special glass-ceramic skeleton structure, in which ZrO₂ and ZrSiO₄ played the role of “Zr nail” to the SiO₂ scale. In addition, the reinforcement mechanism of 0.1Al₂O₃-ZrO₂ layer to the MoSi₂ coating was also discussed.

在纯Mo基底上制备了0.1Al ₂ O ₃ -ZrO ₂增强的MoSi ₂复合涂层，以提高其高温抗氧化性，其中MoSi ₂涂层通过改进的包装硅化工艺制备，然后制备0.1Al ₂ O通过非水解溶胶-凝胶法在制备的MoSi ₂层上生成_3- ZrO ₂层。通过XRD，SEM和EDS研究了氧化暴露前后所制备复合涂层的相组成和微观结构。与单一MoSi ₂的松散结构不同氧化暴露后的0.1Al ₂ O ₃ -ZrO ₂增强的MoSi ₂复合涂层具有相对紧凑的内部结构，具有较小的贯穿厚度裂纹。引入0.1Al ₂ O ₃ -ZrO ₂层可有效地防止氧化过程中在MoSi ₂表面形成的玻璃状SiO ₂氧化皮的开裂和剥落，从而可以使SiO ₂氧化皮在涂层表面上得到很好的稳定。嵌入稳定ZrO ₂和ZrSiO ₄的保护性SiO ₂玻璃鳞片形成相，有助于改善复合涂层的结构稳定性。提出ZrO ₂，ZrSiO ₄和SiO ₂形成一种特殊的玻璃陶瓷骨架结构，其中ZrO ₂和ZrSiO ₄在SiO ₂尺度上起“ Zr钉”的作用。此外，还讨论了0.1Al ₂ O ₃ -ZrO ₂层对MoSi ₂涂层的增强机理。