Thermodynamic analysis of ZrB2-SiC oxidation:: Formation of a SiC-depleted region
Thermodynamic analysis of ZrB2-SiC oxidation:: Formation of a SiC-depleted region
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DOI：
10.1111/j.1551-2916.2006.01329.x
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发表时间：
2007-01-01
影响因子：
3.9
通讯作者：
Fahrenholtz, William G.
中科院分区：
文献类型：
--
作者：
Fahrenholtz, William G.
开发了一个热力学模型来解释1500摄氏度空气中ZrB 2-SiC氧化过程中SiC耗尽层的形成。所提出的模型表明，由（1）富硅层，（2）富锆氧化层，（3）SiC贫化二硼化锆层组成的结构是化学稳定的。由于SiC的活性氧化，SiC贫化层发展。SiC耗尽层中的氧分压计算为在4.0 × 10（-14）和1.8 × 10（-11）Pa之间。尽管SiC经历了主动氧化，但整个过程与被动氧化和保护性表面层的形成一致。
A thermodynamic model was developed to explain the formation of a SiC-depleted layer during ZrB2-SiC oxidation in air at 1500 degrees C. The proposed model suggests that a structure consisting of (1) a silica-rich layer, (2) a Zr-rich oxidized layer, and (3) a SiC-depleted zirconium diboride layer is thermodynamically stable. The SiC-depleted layer developed due to active oxidation of SiC. The oxygen partial pressure in the SiC-depleted layer was calculated to lie between 4.0 x 10(-14) and 1.8 x 10(-11) Pa. Even though SiC underwent active oxidation, the overall process was consistent with passive oxidation and the formation of a protective surface layer.