中文摘要：

在高温钼丝炉内向铁液中分别加入NiMg和SiMg合金进行脱氧,分析过程中溶解氧、全氧、残镁量及夹杂物随时间的变化,并与铝脱氧进行对比。结果表明：加入0.05%的SiMg合金处理后,铁液中溶解氧含量（质量分数）为1.5×10^-6,全氧含量为1.9×10^-5;经SiMg与NiMg合金处理的试样中夹杂物变化基本相同;加入镁合金并保温15min后凝固试样中夹杂物尺寸明显减小,约为2μm,其成分由Mn-Si-Al复合氧化物转变为Mg-Al尖晶石类夹杂物;加入Al并保温15min后,凝固试样中夹杂物尺寸较大,约为5μm,成分为纯Al2O3夹杂物;SiMg合金处理的试样中单位面积上夹杂物数量最少,钢中夹杂物最为细小、分散。

英文摘要：

Deoxidation experiments of molten iron were carried out by adding Al,NiMg and SiMg alloys.The contents of dissolved and total oxygen and residual magnesium were measured,and the changes of inclusions in molten iron with time were investigated.The results show that the contents of dissolved oxygen and total oxygen in the molten iron treated by adding 0.05% SiMg alloy are 1.5×10^-6 and 1.9×10^-5 （mass fraction）,respectively.The changes of inclusions with time are most consistent in the molten iron treated by SiMg and NiMg alloys.The sizes of inclusions in the final simples decrease obviously to about 2 μm and the kind of inclusions changes from Mn-Si-Al multiple oxides to Mg-Al spinel after adding Mg alloys and then holding for 15 min.While the size of inclusions is around 5 μm and the kind of inclusions is pure Al2O3 in the final sample after adding Al and then holding for 15 min.The amount of inclusions per unit area is the least,and the size of them is the most dispersive in the sample treated by SiMg alloy.