摘要
为研究稀土锆酸盐热障涂层的抗热震性能及隔热性能,以Sm2O3和ZrO2为原料,采用固相反应法制备了热喷涂用Sm2Zr2O7粉末,并采用大气等离子喷涂技术在LY12合金表面制备了Sm2Zr2O7热障涂层。利用X射线衍射(XRD)、扫描电镜(SEM)等测试技术研究了Sm2Zr2O7粉末和Sm2Zr2O7涂层的微观组织结构、涂层结合强度和热导率。结果表明:制备的Sm2Zr2O7粉末主要呈短轴状,颗粒内部结合紧密,可满足热喷涂的需要;喷涂前后Sm2Zr2O7相成分没有发生任何变化,具有良好的相稳定性能;Sm2Zr2O7热障涂层组织结构致密,涂层的孔隙率约为14.31%,结合强度约为19.8MPa;在相同的孔隙率下,Sm2Zr2O7涂层的热导率仅为YSZ涂层的37.6%和纳米YSZ涂层的42.1%。
Sm2Zr2O7 powders for thermal spraying were prepared via solid reaction using Sm2O3 and ZrO2 as raw materials.Sm2 Zr2 O7 thermal barrier coatings were then prepared from the powders by atmosphere plasma spraying. The microstructureand phase composition of Sm2Zr2O7 powders and thermal barriercoatings were analyzed by means of X-ray diffraction ( XRD) and scanning electrical microscopy. The adhesion strength and thermal conductivity of Sm2 Zr2 O7 thermal barrier coatings were measured using pulling method and laser - flash method, respectively.Results showed that Sm2 Zr2O7 powders had short - axis shape and compact microstructure, and they could be readily used for thermal spraying. No phase transformation was detected after thermal spraying of Sm2Zr2O7 powders, showing good phase stability.Moreover, the Sm2Zr2O7 thermal barrier coatings had a compact microstructure. It had a porosity and tensile strength of about 14. 31% and 19. 8 MPa, respectively, while its thermal conductivity [0.35 W/(m·K) ] was only 37.6% and 42.1% of that of micro-YSZ coatings [ 0. 93 W/ ( m·K ) ] and nano -YSZ coatings at the same porosity level.
出处
《材料保护》
CAS
CSCD
北大核心
2008年第11期24-27,共4页
Materials Protection
基金
河南工程学院博士基金资助项目(D2007012)
关键词
热障涂层
稀土锆酸盐
等离子喷涂
微观组织
性能
热导率
thermal barrier coatings
rare earth ziroonate
plasma spraying
microstructure
properties
thermal conductivity
