钙处理管线钢中Al_2O_3夹杂物的动力学模型

在热力学计算的基础上,基于未反应核模型,建立了管线钢中Al_2O_3夹杂物变性的动力学模型.计算结果表明,Al_2O_3夹杂物变性过程最难阶段在中段,因此Al_2O_3夹杂物变性的中段应创造良好的夹杂物变性的动力学条件;Al_2O_3夹杂物的尺寸是影响夹杂物变性的重要因素,随着Al_2O_3夹杂物粒径的增加,变性难度急剧增加;本模型计算条件下,只有当钢液中Ca质量分数达到0.0014%时,夹杂物才可能变性为液态钙铝酸盐,钙处理用量不同,Al_2O_3夹杂物变性的产物也不同,应根据Al_2O_3夹杂物变性的目标产物决定用钙量,避免夹杂物变性过度.工业试验较好地验证了本模型的计算结果.

A kinetics model of Al2 O3 inclusions in the treated pipeline steel by calcium

A kinetics model of Al2 O3 inclusions modification in pipeline steel was established according to the thermodynamic calculation and based on the unreacted core model. The results showed that, the most difficult step in Al2 O3 inclusions modification process is in the middle stage. Therefore, a favorable kinetics condition should be created in the middle stage for Al2 O3 inclusions to modificy ,size of the Al2 O3 inclusions is an important factor for the inclusion modification, and the difficulty index dramatically increases with increase of the Al2 O3 inclusions size. Under the calculated conditions of the model, only when the Ca content( mass fraction) in the molten steel reached 0. 0014%, the inclusions can be modified to liquid calcium - aluminate and modification product of the Al2 O3 inclusions is different with the calcium amount. So calcium content in the treatment process should be depended on the target product of Al2 O3 inclusions modification. The industrial test verified the results of the authors model well.