Oxidation Mechanisms in MgO-C Refractories

作     者：B.Hashemi Z.Ali Nemati S.K.Sadrnezhaad 

作者机构：Department of Materials Science and Engineering Department of Materials Science and Engineering Department of Materials Science and Engineering Sharif University of Technology TehranIran11365-9466Sharif University of Technology TehranIran11365-9466Sharif University of Technology TehranIran11365-9466 

出 版 物：《China's Refractories》 (中国耐火材料（英文版）)

年 卷 期：2004年第13卷第2期

页      面：13-20页

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

主　　题：MgO Carbon Diffusion Refractories Oxidation 

摘      要：An investigation on the oxidation mechanism of the graphite in the MgO-C refractory materials is helpful to improving both the quality of these materials and to preventing and/or lowering of the adverse effects of the high-temperature oxidation. In this research, the oxidation behavior of the MgO-C refractories containing 5～20 wt% graphite was studied via weight-loss method. Atmospheric air was used for oxidation at temperatures ranging from 900℃ to 1300°C and the experimental data were compared with those obtained from the dimensionless kinetic equations of the shrinking core model, in order to determine the oxidation mechanisms of the refractories. The best fit was achieved with the porous layer diffusion control regime. Oxidation mechanism tends, however, to slightly deviate from pure pore diffusion control to pore diffusion-external gas transfer regime in the samples having more graphite contents (e.g. 20%).