铬铁高温合金恒温氧化动力学行为研究

Kinetic Behavior of Isothermal Oxidation of Cr⁃Fe High⁃Temperature Alloy

基于金属氧化理论和扩散控速机制,建立了铬铁合金平板高温氧化动力学模型,研究了合金成分、温度、气氛、氧分压等因素对合金氧化行为的影响。结果表明,该氧化动力学模型可较好地定量描述铬铁合金平板氧化过程,模型拟合结果与实验结果吻合程度较好。铬铁合金的氧化特征时间tΦ约为(3~4)×10^(-14)s,氩气中tΦ随合金中铁含量增加总体呈下降趋势,氧分压对合金氧化速率的影响不显著,铬铁合金在氩气中的氧化平衡产物均为Cr_(2)O_(3)。依据高温合金的抗氧化标准,铬铁合金在空气中可达到抗氧化和次抗氧化的评级标准。

Based on the theory of metal oxidation and the mechanism of diffusion rate control,a kinetic model was established for high temperature oxidation of Cr⁃Fe alloy plate.The effects of composition,temperature,atmosphere,partial pressure of oxygen on the oxidation behavior of the alloy were studied.The results show that the established oxidation kinetic model can quantitatively present an oxidation process of Cr⁃Fe alloy plate,by which the calculated results are in good agreement with the experimental results.The oxidation characteristic time(tΦ)of the Cr⁃Fe alloy is about(3-4)×10^(-14) s,and tΦin argon atmosphere decreases gradually with the increase of Fe content in the alloy.Partial pressure oxygen doesn′t bring significant impact to the oxidation rate of alloy,and all products from the equilibrium oxidation of alloy in argon atmosphere are Cr_(2)O_(3).According to the standard of oxidation resistance of superalloy,Cr⁃Fe alloy in air atmosphere can meet the rating standards for oxidation resistance and secondary oxidation resistance.