Effect of carbon content on the oxidation resistance and kinetics of MgO-C refractory with the addition of Al powder
Effect of carbon content on the oxidation resistance and kinetics of MgO-C refractory with the addition of Al powder
复制标题
碳含量对添加Al粉的MgO-C耐火材料抗氧化性能和动力学的影响
DOI：
10.1016/j.ceramint.2019.10.010
复制
发表时间：
2020-02-15
影响因子：
5.2
通讯作者：
Yuan, Lei
中科院分区：
文献类型：
--
作者：
Liu, Zhaoyang;Yu, Jingkun;Yuan, Lei
研究了MgO - C耐火材料的碳含量对其物理性能、抗氧化性和动力学的影响。通过计算氧化相关参数以及分析物相和微观结构的演变，研究了氧化机理。MgO - C耐火材料的抗氧化性受碳通过形成MgO组成层的间接氧化的影响。间接氧化的作用导致碳含量为3 wt%的MgO - C耐火材料在1600℃烧制时比在1400℃烧制时具有更低的氧化速率和失重率。基于缩核模型的氧化动力学结果表明，有效扩散系数和完全氧化时间随着碳含量的增加而增加。这个看似矛盾的结果主要是由于在氧化过程中碳的摩尔密度的影响大于有效扩散系数的影响。
The effect of carbon content of MgO-C refractory was studied with respect to the physical properties, oxidation resistance and kinetics. The oxidation mechanism was investigated by calculating the relevant parameters of oxidation and analyzing the evolutions of phases and microstructures. The oxidation resistance of MgO-C refractory was influenced by the indirect oxidation of carbon through the formation of the MgO constituent layer. The effect of indirect oxidation resulted in the MgO-C refractory with 3 wt% carbon content having a lower oxidation rate and weight loss rate when fired at 1600 degrees C than when fired at 1400 degrees C. The oxidation kinetics results based on shrinking core model showed that the effective diffusion coefficient and full oxidation time increased with the increasing of carbon content. This seemingly paradoxical result was mainly due to the effect of the molar density of carbon prevailing over that of the effective diffusion coefficient in the oxidation process.