预合金化工艺对铝脱氧钢洁净度的影响  

Effect of pre-alloying process for cleanliness of Al-killed steel

作　　者：程林 王哲[2] 胡志远 任强 张立峰 CHENG Lin;WANG Zhe;HU Zhiyuan;REN Qiang;ZHANG Lifeng(College of Materials Science and Engineering,Yanshan University,Qinhuangdao 066044,Hebei,China;School of Mechanical Engineering,Yanshan University,Qinhuangdao 066044,Hebei,China;Shougang Zhixin Electromagnetic Materials(Qian’an)Co.,Ltd.,Qian’an 064404,Hebei,China;School of Mechanical and Material Engineering,North China University of Technology,Beijing 100144,China)

机构地区：[1]燕山大学材料工程学院,河北秦皇岛066044 [2]燕山大学机械工程学院,河北秦皇岛066044 [3]首钢智新电磁材料(迁安)股份有限公司,河北迁安064404 [4]北方工业大学机械与材料工程学院,北京100144

出　　处：《钢铁》2025年第1期51-65,共15页Iron and Steel

基　　金：国家重点研发计划资助项目(2023YFB3709900);国家自然科学基金资助项目(U22A20171,52104342)。

摘　　要：低碳铝镇静钢的脱氧方式主要为铝脱氧,而钢液中不同异质成核位点的出现会对后续脱氧产物的形核生长产生影响。通过实验室试验对铝镇静钢的预合金化工艺进行了研究,使用酸溶法和电解法对钢中夹杂物的三维形貌及数量进行了表征。热力学计算以及试验表明,添加1.0%A(l质量分数)时钢液进行的复合脱氧处理中热力学稳定相为Al_(2)O_(3)相,不同脱氧工艺之间的差异体现在钢液成分和夹杂物形貌上。通过铝氧反应试验讨论了不同预合金化工艺对铝脱氧形成Al_(2)O_(3)夹杂物的形核、生长、形貌、尺寸及数量的影响,发现在实验室试验条件下,钢液中Al_(2)O_(3)夹杂物主要有球状、树枝状、多边形块状和团簇状4大类形貌。预先存在FeO的铝氧反应主要涉及Al_(2)O_(3)夹杂物形核析出阶段、形貌演化阶段和团聚烧结阶段。其余铝氧反应在反应初期涉及不同夹杂物改性过程。粗糙界面局部过饱和度较高时容易形成球状形貌且不易成簇。界面局部过饱和度较低时容易形成刻面形貌,局部氧过饱和度较高时容易形成树枝状形貌,随着氧过饱和度的降低会逐渐向花瓣状、片层状和板条状演变。预先存在SiO2夹杂物的铝氧反应中夹杂物的数密度最高,其平均三维尺寸最低。钢液中Al_(2)O_(3)夹杂物的形貌会受到预先存在的夹杂物、过饱和度、脱氧剂和溶解氧、过冷度、结构的影响。The deoxidation mode of low carbon aluminum killed steel is mainly aluminum deoxidation,and the appearance of different heterogeneous nucleation sites in molten steel affects the nucleation growth of subsequent deoxidation products.The pre-alloying process of aluminum-killed steel was studied by laboratory experiments,the three dimensional morphology and quantity of inclusions were characterized by acid dissolution and electrolysis.The thermodynamic calculation and experiments showed that the thermodynamic stable phase of the composite deoxidation treatment with the addition of 1.0%A(l mass fraction)was Al_(2)O_(3) phase,and the differences between different deoxidation processes were reflected in the composition of molten steel and the morphology of inclusions.The influences of different pre-alloying processes on the nucleation,growth,morphology,size and quantity of Al_(2)O_(3) inclusions formed by aluminum deoxidation were discussed by aluminum-oxygen reaction experiment.The aluminumoxygen reaction with pre-existing FeO inclusions mainly involved the nucleation and precipitation stage of Al_(2)O_(3) inclusion,the stage of morphology evolution and the stage of agglomeration sintering.The rest of the aluminum and oxygen reaction at the beginning of the reaction involving different inclusions modification process.It was found that the Al_(2)O_(3) inclusions in molten steel were mainly spherical,dendritic,polygonal block and cluster morphology under laboratory experimental conditions.When the local supersaturation of the rough interface was high,it was easy to form spherical shape and not easy to cluster.When the local supersaturation of the interface was low,it was easy to form a facet shape,and when the local oxygen supersaturation was high,it was easy to form a dendritic shape.With the decrease of oxygen supersaturation,it gradually evolved into a petal shape,lamellar shape and strip shape.The aluminum-oxygen reactions with pre-existing SiO2 inclusions had the highest number density of inclusions and the lowest

关 键 词：预合金化工艺 铝镇静钢 夹杂物 形貌演变 过饱和度 铝氧反应 低碳 钢液 脱氧剂 

分 类 号：TF704.2[冶金工程—钢铁冶金]