摘要
采用电镀Pt+气相渗Al和电子束物理气相沉积(EB-PVD)技术,在DZ406合金和DZ125合金表面制备了PtAl粘结层和1.0Gd_(2)O_(3)-2.0Yb_(2)O_(3)稀土掺杂改性YSZ(GYb-YSZ)陶瓷层,研究了PtAl/GYb-YSZ热障涂层在1250℃下的高温燃气热冲击性能。结果表明,DZ406合金+PtAl/GYb-YSZ热障涂层的热冲击寿命为10000次,DZ125+PtAl/GYb-YSZ热障涂层的热冲击寿命为7800次。两种合金表面涂层的失效均发生在粘结层和陶瓷层界面处,粘结层氧化生成的热生长氧化膜在热冲击过程中不断增厚,造成粘结层和陶瓷层界面处裂纹萌生并扩展,最终导致涂层剥落失效。而DZ125合金中的Hf元素扩散至热生长氧化膜中,破坏了氧化膜的完整性,氧化膜快速生长增厚导致涂层过早失效。
The PtAl bond coat was firstly deposited on the DZ406 and DZ125 alloys by the electroplating Pt and vapor infiltration Al method,and then the1.0Gd_(2)O_(3)-2.0Yb_(2)O_(3) co-doped modified YSZ(GYb-YSZ)ceramic layer was prepared by electron beam physical vapor deposition(EB-PVD)method.The high temperature thermal shock performance of PtAl/GYb-YSZ thermal barrier coatings(TBCs)was investigated at 1250℃.The results show that the thermal shock life of DZ406 alloy+PtAl/GYb-YSZ TBCs is 10000 times,and that of DZ125 alloy+PtAl/GYb-YSZ TBCs is 7800 times.The coating failure mainly occurs at interface between the bond coat and the ceramic layer.During the thermal shock process,the thermally grown oxides(TGO)are formed and thickened by the oxidation of the bond coating,resulting in cracks initiation and propagation at interface between the bond coating and the ceramic layer,and eventually lead to coating spallation.The Hf element in the DZ125 alloy diffuses into the TGO,which destroys the integrity of the oxide film.The rapid growth and thickening of the oxide film lead to premature failure of the coating.
作者
袁珂
方向
黄子琳
曾佳敏
王强
Yuan Ke;Fang Xiang;Huang Zilin;Zeng Jiamin;Wang Qiang(Aecc Hunan Ariation PowerplantResearch Institute,Zhuzhou 412002,China)
出处
《中国稀土学报》
EI
CAS
CSCD
北大核心
2024年第2期268-274,I0003,共8页
Journal of the Chinese Society of Rare Earths
基金
国家科技重大专项经费项目(J2019-VIII-0002-0163)资助。
关键词
稀土
热障涂层
燃气热冲击
热生长氧化膜
剥落失效
rare earth
thermal barrier coatings
high temperature thermal shock
thermally grown oxides
premature failure
