In this work,the microstructure evolution,thermal expansion,thermal conductivity,and thermal shock resistance properties of the plasma-sprayed Xl-Gd_(2)SiO_(5),X2-Y_(2)SiO_(5),and X2-Er_(2)SiO_(5)coatings were evaluat...In this work,the microstructure evolution,thermal expansion,thermal conductivity,and thermal shock resistance properties of the plasma-sprayed Xl-Gd_(2)SiO_(5),X2-Y_(2)SiO_(5),and X2-Er_(2)SiO_(5)coatings were evaluated and compared by experimental measurement and theoretical exploration.Results showed that significant microstructure evolution such as crystallization of amorphous phase,grain growth,and defects reduction was observed in the RE_(2)SiO_(5)coatings after thermal aging at 1400℃.The Xl-Gd_(2)SiO_(5)coating exhibited higher CTE values than the X2-Y_(2)SiO_(5)and X2-Er_(2)SiO_(5)coatings,which was related to their crystal structure.The thermal conductivity of thermal-aged RE_(2)SiO_(5)coating was much higher than that of the as-sprayed RE_(2)SiO_(5)coating,and thermal conductivity was determined not only by crystal structure but also mainly by the microstructure of the coatings.The X2-Y_(2)SiO_(5)and X2-Er_(2)SiO_(5)coatings with lower thermal mismatch stre s ses presented much better thermal shock resistance than the X1-Gd_(2)SiO_(5)coating.展开更多
基金financially supported by the National Key R&D Program of China(No.2018YFB0704400)the National Science and Technology Major Project(No.2017-VI-0020-0092)+2 种基金the Shanghai Technical Platform for Testing on Inorganic Materials(No.19DZ2290700)the Shanghai Sailing Program(No.19YF1453900)the Natural Science Foundation of Shanghai(No.20ZR1465700)。
文摘In this work,the microstructure evolution,thermal expansion,thermal conductivity,and thermal shock resistance properties of the plasma-sprayed Xl-Gd_(2)SiO_(5),X2-Y_(2)SiO_(5),and X2-Er_(2)SiO_(5)coatings were evaluated and compared by experimental measurement and theoretical exploration.Results showed that significant microstructure evolution such as crystallization of amorphous phase,grain growth,and defects reduction was observed in the RE_(2)SiO_(5)coatings after thermal aging at 1400℃.The Xl-Gd_(2)SiO_(5)coating exhibited higher CTE values than the X2-Y_(2)SiO_(5)and X2-Er_(2)SiO_(5)coatings,which was related to their crystal structure.The thermal conductivity of thermal-aged RE_(2)SiO_(5)coating was much higher than that of the as-sprayed RE_(2)SiO_(5)coating,and thermal conductivity was determined not only by crystal structure but also mainly by the microstructure of the coatings.The X2-Y_(2)SiO_(5)and X2-Er_(2)SiO_(5)coatings with lower thermal mismatch stre s ses presented much better thermal shock resistance than the X1-Gd_(2)SiO_(5)coating.
