Hot corrosion behavior of Yb2Si2O7 ceramic by NaVO3 and V2O5 at 700° to 900°

2019 International Conference on Advanced Electronic Materials, Computers and Materials Engineering

无线电电子学;计算机科学;材料科学

Zhang, Yongqiu^1 ; Sun, Daqian^1 ; Ren, Zhenan^1 ; Zou, Binglin^2

Key Laboratory of Automobile Materials, School of Materials Science and Engineering, Jilin University, Changchun

130025, China^1

State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin

130022, China^2

关键词: Corrosion products;    Corrosion reaction;    Driving forces;    Large elongation;    Nucleation rate;    Structural characteristics;    Temperature range;    Test temperatures;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/563/2/022022/pdf
DOI  :  10.1088/1757-899X/563/2/022022

来源: IOP

【 摘 要 】

To better understand the hot corrosion behavior of Yb2Si2O7 ceramic in molten NaVO3 and V2O5, corrosion experiments were performed using sintered Yb2Si2O7 bulk ceramics with NaVO3 and V2O5 coatings at temperature range of 700 to 900 °C in air. Corrosion products of YbVO4 and SiO2 were identified under NaVO3 corrosion. But only YbVO4 was found under V2O5 corrosion with some residual corrosion agent. In above two conditions, the corrosion products of YbVO4 have the same crystallographic structural characteristic, but morphology has significant difference. In the first case, YbVO4 is rod-like with a tetrahedral cone at each end because of NaVO3 being weak acid to lead to lower driving force for the corrosion reactions. Thus corrosion products of YbVO4 grew with less nuclei and large elongation. However, V2O5 showed strong acid with strong driving force bringing higher nucleation rate and suppressing the growth of YbVO4, which resulted in granular YbVO4. And the size of granular YbVO4 crystals increased slightly with test temperature rising.