LaMgAl11O19涂层的CMAS侵蚀行为研究

Corrosion Behavior of CMAS on LaMgAl11O19 Coating

摘要:

为了研究服役过程中38CaO-5MgO-8AlO_1.5-49SiO₂(CMAS)对镁基六铝酸镧(LaMgAl₁₁O₁₉)的高温侵蚀行为,利用大气等离子喷涂技术制备了LaMgAl₁₁O₁₉涂层。本文通过SEM、EDS和XRD表征了1050℃、1250℃下LaMgAl₁₁O₁₉涂层被CMAS侵蚀后的微观组织和相结构。研究表明,LaMgAl₁₁O₁₉涂层中在1250℃被侵蚀24 h后的腐蚀产物是CaAl₂Si₂O₈和MgAl₂O₄。此外,通过研究侵蚀层厚度与侵蚀温度、侵蚀时间的关系,计算得到了在1050℃~1250℃温度下,CMAS侵蚀LaMgAl₁₁O₁₉涂层的反应活化能为94.1 kJ/mol。

Abstract:

The LaMgAl₁₁O₁₉ was prepared by air plasma spraying technology to investigate the corrosion behavior of 38CaO-5MgO-8AlO_1.5-49SiO₂ (CMAS) on high temperature. The microstructure, element distribution and phase composition of LaMgAl₁₁O₁₉ coating before and after CMAS corrosion were investigated. The results show that CaAl₂Si₂O₈ and MgAl₂O₄ can be observed in LaMgAl₁₁O₁₉ coating after corroded at 1250 ℃ for 24 h. Besides, according to the thickness of corroded zone in LaMgAl₁₁O₁₉ coating, the apparent activation energy in the temperature range of 1050~1250 ℃ is 94.1 kJ/mol.