An elastic phase field model for thermal oxidation of metals: Application to zirconia
An elastic phase field model for thermal oxidation of metals: Application to zirconia
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DOI：
10.1016/j.commatsci.2014.03.042
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发表时间：
2014-06
影响因子：
3.3
通讯作者：
M. A. Zaeem;H. Kadiri
中科院分区：
文献类型：
--
作者：
M. A. Zaeem;H. Kadiri
建立了金属非选择性氧化的多相场模型，该模型同时考虑了氧化动力学和应力的产生。相场制剂涉及一个非保守的相场变量作为标记的金属基板，氧化皮，和一个流体相含有氧气，和一个保守的相场变量表示的氧的浓度。将相场变量的演化方程耦合到力学平衡方程中，以研究氧化膜和底层金属中应力产生的演化。控制方程在有限元框架中求解。该相场模型预测了氧化物层和金属-氧化物界面处的氧成分深度和应力分布。该模型被证明是成功的，在900 °C氧化的Zr-4合金的氧化物厚度和生长应力的预测观察到的演变。相场模拟的结果表明，氧化时产生的应力往往会减缓氧化动力学，这大大提高了模型的预测实验数据。
A multi-phase field model was developed for non-selective oxidation of metals which captures both the oxidation kinetics and stress generation. Phase field formulation involved a non-conserved phase field variable as the marker for the metallic substrate, oxide scale, and a fluid phase containing oxygen, and a conserved phase field variable representing the concentration of oxygen. The evolution equations of the phase field variables were coupled to the mechanical equilibrium equations to investigate the evolution of stress generation in both the oxide scale and the underlying metal. The governing equations were solved in a finite element framework. This phase field model predicts the oxygen composition depth and stress profiles in the oxide layer and at the metal–oxide interface. The model was proven successful in predicting the observed evolution of oxide thickness and growth stresses for Zircaloy-4 oxidized at 900 °C. The results of phase field simulations showed that the generation of stresses upon oxidation tends to slow down the oxidation kinetics, and this substantially improved the model predictability of experimental data.