700BL钢冶炼全流程非金属夹杂物演变及热力学分析  

Thermodynamic analysis and evoltion of non-metallic inclusions in the whole production process of 700BL steel

作　　者：郭斌 单庆林[2] 石晓伟 路博勋 潘宏伟 王举金 张立峰 Guo Bin;Shan Qinglin;Shi Xiaowei;Lu Boxun;Pan Hongwei;Wang Jujin;Zhang Lifeng(School of Mechanical and Materials Engineering,North China University of Technology,Beijing 100144,China;Tangshan Iron and Steel Group Co.,Ltd.,Tangshan 063000,Hebei)

机构地区：[1]北方工业大学机械与材料工程学院,北京100144 [2]唐山钢铁集团有限责任公司,河北唐山063000

出　　处：《河北冶金》2025年第2期12-19,共8页Hebei Metallurgy

基　　金：国家重点研发计划(2023YFB370990);国家自然科学基金(U22A20171,52304340);河钢重点科技项目(HG2022125)。

摘　　要：通过全流程取样分析700BL钢中各成分含量及夹杂物形貌和成分分布变化,研究了钙处理对钢中夹杂物成分变化的影响,以及在冷却和凝固过程中夹杂物析出情况,并与FactSage热力学计算结果进行对比。研究结果表明,在精炼过程中随着钙处理的进行,钢中夹杂物由纯Al_(2)O_(3)转变为59.68%Al_(2)O_(3)-3.10%MgO-37.22%CaO的复合夹杂物,钛合金化后钢液中形成含钛的复合夹杂物。在连铸坯和轧板中TiN以钙铝酸盐夹杂物为核心析出或直接均质形核析出,其占比超过50%。热力学计算结果与实际结果在成分上大致相同,当钢中钙含量由5 ppm增加至15 ppm时,夹杂物由Al_(2)O_(3)和CaO·6Al_(2)O_(3)转变为CaO·2Al_(2)O_(3)和液态夹杂物,当钢冷却至1475℃左右时大量TiN开始快速析出。In order to study the effect of calcium treatment on the composition of inclusions in 700BL steel and the precipitation of inclusions during the cooling and solidification,the whole process sampling was conducted to study the evolution of steel components and the morphology and composition distribution of inclusions.Results were compared with thermodynamic calculation results of FactSage.The results show that calcium treatment modified the inclusion from the pure Al_(2)O_(3)to 59.68%Al_(2)O_(3)-3.10%MgO-37.22%CaO during the process of refining,and the inclusion was modified the composite inclusions containing titanium after adding titanium.Titanium nitride inclusion was precipitated on a core of calcium aluminate inclusion or directly at the slab and rolling plates,which accounted for more than 50%.Thermodynamic results could reveal measured results in terms of composition.Inclusions were modified from Al_(2)O_(3)and CaO·6 Al_(2)O_(3)to CaO·2 Al_(2)O_(3)and liquid inclusions when the calcium content in the steel increased from 5 ppm to 15 ppm.A large amount of TiN inclusion precipitated rapidly when the steel was cooled to about 1475℃.

关 键 词：700BL钢 非金属夹杂物 热力学 FactSage 钛合金化 

分 类 号：TF777[冶金工程—钢铁冶金]