Chromia scale growth in alloy oxidation and the reactive element effect
Chromia scale growth in alloy oxidation and the reactive element effect
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DOI：
10.1149/1.2220920
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发表时间：
1993-10
影响因子：
3.9
通讯作者：
B. Pieraggi;R. Rapp
中科院分区：
文献类型：
--
作者：
B. Pieraggi;R. Rapp
涉及同时阳离子和阴离子扩散的垢生长的动力学分析，以及阴离子扩散与阳离子扩散受阻，提出并与文献中的实验数据进行比较。显着减少的结垢动力学的生长氧化铬纯铬和铁，镍，或钴基合金是由于消除阳离子扩散的阳离子反应步骤在金属/规模界面的阻塞。大的高电荷反应性元素（RE）离子在金属/氧化皮界面处分离并钉扎错配位错，错配位错的攀爬另外用于产生间隙阳离子（或消除空位）。然后，规模的增长必须进行氧扩散阴离子空位，对应于横向攀登的错位（在单原子步骤的反应）在金属/规模界面。中毒界面模型提供了一个解释的活性元素效应（REE），这是一致的四个众所周知的稀土元素的特点。
An analysis for the kinetics of scale growth involving simultaneous cation and anion diffusion, and for anion diffusion with blocked cation diffusion, is presented and compared to experimental data in the literature. The significant reduction in scaling kinetics for the growth of chromia on pure Cr and on Fe-, Ni-, or Co-base alloys is attributed to the elimination of cation diffusion by the blocking of the cationic reaction step at the metal/scale interface. Large highly charge reactive element (RE) ions segregate at the metal/scale interface and pin the misfit dislocations whose climb otherwise serves to create interstitial cations (or annihilate vacancies). Then scale growth must proceed by oxygen diffusion over anion vacancies, corresponding to the lateral climb of misorientation dislocation (reaction at monoatomic steps) at the metal/scale interface. This poisoned interface model provides an interpretation for the reactive element effect (REE) which is consistent with the four well-known REE characteristics.