High temperature corrosion of silicon nitride composite ceramics in sulfur-oxygen environments
来源期刊：中国有色金属学报(英文版)2003年第2期
论文作者：王昕 孙康宁 李静 于薛刚 尹衍升 杨连喜
文章页码：311 - 314
Key words：Si3N4 composite ceramics; sulfidation; oxidation; corrosion
Abstract: High temperature corrosion behavior of Si3N4-8%Al2O3(volume fraction) composite ceramics in sulfur-oxygen environments was studied. At 1150℃ and 1350℃, the corrosion processes follow parabolic law with parabolic rate constants (Kp) of 1.45×10-9g2·cm-4·s-1 and 7.92×10-9g2·cm-4·s-1, respectively. The corrosion mechanisms are different at different temperatures. At 1150℃, the corrosion of the material is due to the destruction of SiO2 layer caused by sulfur and the active oxidation corrosion. At 1350℃, the diffusion of additives and impurity elements to grain boundaries and outward to surface layers lead to the formation, growth and break of bubbles, which accelerates the corrosion rate of the Si3N4 ceramics.
