Abstract A kinetic model of the dissolution of Al2O3 into mould fluxes with low SiO2 content was established, and the restrictive step of the dissolution process was investigated by employing a rotating cylinder method. Then, the effects of the relative moving speed between the Al2O3 sample and the flux as well as the effects of the temperature and composition on the dissolution rate of Al2O3 were analysed. The results showed that the dissolution of Al2O3 is controlled by the diffusion in the product layer. The dissolution rate increases with the increase in the relative moving speed and temperature. The activation energy of the dissolution of Al2O3 into mould fluxes A-1, A-2, and B were 150.8 kJ mol−1, 156.1 kJ mol−1, and 131.4 kJ mol−1, respectively. The dissolution accelerates with increasing (CaO+BaO)/(Al2O3 +SiO2) ratio and Na2O, Li2O, B2O3, and F− contents. The result of the analysis of the Al2O3/flux interface by scanning electron microscopy–energy dispersive X-ray spectroscopy showed that a product layer was formed in the dissolution process, with interfacial products BaO·6Al2O3 and BaO·2CaO·4Al2O3.

中文翻译：

---

Al2O3 在低 SiO2 含量保护渣中的溶解行为

摘要 建立了Al2O3在低SiO2含量保护渣中溶解的动力学模型，并采用转筒法研究了溶解过程的限制步骤。然后，分析了Al2O3样品与助熔剂之间的相对移动速度以及温度和成分对Al2O3溶解速率的影响。结果表明，Al2O3 的溶解受产物层中的扩散控制。溶解速率随着相对移动速度和温度的增加而增加。Al2O3 溶解到保护剂 A-1、A-2 和 B 中的活化能分别为 150.8 kJ mol-1、156.1 kJ mol-1 和 131.4 kJ mol-1。随着 (CaO+BaO)/(Al2O3 +SiO2) 比值和 Na2O、Li2O、B2O3、和 F- 含量。扫描电子显微镜-能量色散X射线光谱分析Al2O3/助熔剂界面的结果表明，在溶解过程中形成了产物层，界面产物为BaO·6Al2O3和BaO·2CaO·4Al2O3。