摘要
采用高能等离子喷涂技术制备了Sm2Zr2O7热障涂层,用X射线衍射(XRD)、扫描电镜(SEM)等手段研究了涂层的相成分、微观组织;采用拉伸法和水淬法测试了涂层的结合强度及热冲击性能。结果表明,喷涂前后Sm2Zr2O7相成分未发生变化,表现出良好的相稳定性能。所制备的Sm2Zr2O7涂层结构致密,涂层各界面结合紧密。涂层的孔隙率仅为4.72%,结合强度为29MPa。涂层在经历20次热冲击后从表面层/金属粘结层界面处脱落,熔融颗粒内部纵向显微裂纹及熔融颗粒之间彼此分离所形成的横向裂纹的共同作用导致了涂层的失效。
Sm2Zr2O7 thermal barrier coatings were prepared by high energy plasma spraying technology,Phase and microstructure of the coatings were studied by X-ray diffraction（XRD） and scanning electron microscope（SEM）.Bonding strength and thermal shocking property of the coatings were investigated by pulling test and water quenching method,respectively.Results show that there is no change of phase of Sm2 Zr2 O7 powders after thermal spraying,which shows better phase stability.The coatings have a compact microstructure and the interface bind tightly between Sm2 Zr2 O7 coating,NiCoCrAlY bonding layer and subtrate are obtained.Porosity in the coatings is about 4.72%.Its bonding strength is 29 MPa which is higher than that of Sm2 Zr2 O7 thermal barrier coating prepared by atmospheric plasma spraying.This coating spalls at the interface between the top Sm2 Zr2 O7 layer and NiCoCrAlY metal bonding layer after twenty thermal cycles.The lognitudinal micro-carcks melted powder particles and transverse cracks formed by seperation of the melted particles lead to the spalling of the coatings..
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2011年第2期112-118,共7页
Transactions of Materials and Heat Treatment
基金
河南工程学院博士基金资助项目(D2007012)
关键词
等离子喷涂
热障涂层
微观组织
热冲击
plasma spraying
thermal barrier coatings
microstructure
thermal shocking
