摘要
采用激光对大气等离子喷涂7YSZ热障涂层进行表面重熔处理,探讨基体预热和Al_(2)O_(3)溶胶涂敷对激光重熔层裂纹愈合的影响,研究处理后热障涂层的耐CMAS熔盐腐蚀性能。结果表明:涂层经过激光重熔和基体预热后的激光重熔处理后,与未经重熔处理涂层的CMAS腐蚀厚度基本相同;而采用表面Al_(2)O_(3)溶胶涂敷加激光重熔的热障涂层的CMAS腐蚀厚度明显减小,表明Al_(2)O_(3)溶胶涂敷加激光重熔工艺可以有效地减轻CMAS熔盐侵蚀,其机理是表面形成的Al_(2)O_(3)薄膜溶于CMAS后生成了难熔晶体钙长石,降低了熔盐的流动性和腐蚀性。
7%yttria stabilized zirconia(7YSZ)thermal barrier coatings(TBCs)prepared by air plasma spray were laser-remelted,and subsequently pre-heated and Al_(2)O_(3) sol-gel repaired for restraining the crack growth in the remelted coatings.The as-prepared coatings were exposed to high temperature molten CaO-MgO-Al_(2)O_(3)-SiO_(2)(CMAS)to explore their corrosion resistance.The results show that both the laser remelted and the pre-heated,the laser-remelted coatings are densified by CMAS attack.In addition,the thickness of the densified layers is on the same order of that of the non-remelted coatings.Despite of this,the densified layer in the laser remelted coating repaired by Al_(2)O_(3) sol-gel is much thinner than the other coatings.This indicates that Al_(2)O_(3) sol-gel repairing coupling with laser-remelted method can effectively improve the CMAS resistance of 7YSZ TBCs due to the refractory anorthite generated during corrosion process.This refractory compound produced between CMAS and Al_(2)O_(3) sol-gel is capable to decrease the mobility and corrosivity of the CMAS.
作者
赵长浩
杨玲伟
肖学仁
张军
潘伟
ZHAO Changhao;YANG Lingwei;XIAO Xueren;ZHANG Jun;PAN Wei(Hypervelocity Aerodynamics Institute,China Aerodynamics Research and Development Center,Mianyang 621000,Sichuan,China;State Key Laboratory of New Ceramics and Fine Processing,Tsinghua University,Beijing 100084,China)
出处
《航空材料学报》
CAS
CSCD
北大核心
2022年第1期40-49,共10页
Journal of Aeronautical Materials
基金
国家自然科学基金项目(91960104,51472135)
中国空气动力研究与发展中心基础前沿项目(KT-JCQY-2019-012)。
