铁精粉还原炉用Si_3N_4(Sialon)/SiC材料在H_2O—H_2—N_2气氛中热力学计算分析

Thermodynamic Analyse of Si_3N_4/SiC and Sialon/SiC In H_2O-H_2-N_2 Environments

根据热力学原理对Si—C—N—H—O五元系统进行了平衡状态下的相稳定性计算,绘制了在1 073 K和1 223 K下的SiC、Si_3N_4、Si_2N_2O和SiO_24个稳定相的稳定性与N_2分压和H_2O分压的关系图,即优势区域图,分析了其凝聚相的稳定区域。同时结合SEM显微结构分析氢气还原炉中Si_3N_4/SiC和Sialon/SiC制品抗H_2O—H_2—N_2气氛的侵蚀性能。

The phase stability in equilibrium of the Si—C—N—H—O system was calculated according to thermodynamics fundamental principles.The phase stability diagrams（predominance area phase diagram） of SiC,Si_3N_4,Si_2N_2O and SiO_2 at 1 073 K and 1 223 K were constructed as a function of N_2 and H_2O partial pressures,thus the phase stability area of every condensed phase were analyzed, and SEM photograph before and after corroding were analyzed.It can reasonably analyze the corrosion resistance of Si_3N_4/SiC and Sialon/SiC products to H_2O—H_2—N_2 environments.