Synthesis of yttria by aqueous sol-gel route to develop anti-CMAS coatings for the protection of EBPVD thermal barriers
Synthesis of yttria by aqueous sol-gel route to develop anti-CMAS coatings for the protection of EBPVD thermal barriers
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DOI：
10.1016/j.ceramint.2016.05.169
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发表时间：
2016-09
影响因子：
5.2
通讯作者：
Elodie Delon;F. Ansart;S. Duluard;J. Bonino;A. Malie;A. Joulia;Philippe Gomez
中科院分区：
文献类型：
--
作者：
Elodie Delon;F. Ansart;S. Duluard;J. Bonino;A. Malie;A. Joulia;Philippe Gomez
采用溶胶-凝胶法制备了抗CMAS氧化钇涂层。通过在聚合基质中自燃烧钇前体来制备具有受控形态的氧化钇粉末。评估了水基溶胶的关键参数的影响。事实上，初始溶胶的pH值和热处理的温度在氧化钇粉末的形态和晶粒尺寸中起主要作用。为了防止CMAS的渗透，提出在水性溶胶的pH=1下合成氧化钇粉末，干燥溶胶并在900 °C下加热。通过溶胶-凝胶法优化了氧化钇薄膜的制备和沉积条件，获得了高比表面积的氧化钇薄膜。它们促进与熔融CMAS的相互作用，从而限制位于下方的热障涂层的降解。结果表明，在1250 °C保温15 min甚至1 h后，氧化钇涂层对CMAS的渗透都有较好的抑制作用。
Anti-CMAS yttria coatings have been prepared by sol-gel routes. Yttria powders with controlled morphology are prepared via auto-combustion of yttrium precursors in a polymerized matrix. The influence of key parameters of the water-based sols is assessed. Indeed, the pH of the initial sol and the temperature of thermal treatment play a major role in the morphology and grain size of yttria powders. To prevent infiltration of CMAS, yttria powders are proposed to be synthesized at pH=1 of the aqueous sol, with drying of the sol and heating at 900 °C. After optimization of the synthesis and deposition conditions via sol-gel route, yttria-based coatings with high specific surface area are obtained. They promote the interaction with melt CMAS and consequently limit the degradation of the thermal barrier coatings situated underneath. It was proved that anti-CMAS yttria coating is effective against the infiltration of CMAS at 1250 °C for 15 min and even 1 h.