摘要
铝脱氧中锰钢精炼过程中易形成尖晶石类夹杂物,这类硬质夹杂物会恶化中锰钢的疲劳性能,易导致钢材功能失效引发事故。采用稀土Ce处理对中锰钢中尖晶石类硬质夹杂物进行改质处理。为了阐明夹杂物的改质机理,开展了高温模拟实验。实验结果表明,Ce处理后,尖晶石夹杂物转变为稀土夹杂物,且随着TO含量的降低,稀土夹杂物类型为CeAlO_(3)→CeAlO_(3)+Ce_(2)O_(2)S→Ce_(2)O_(2)S。铈对尖晶石夹杂物的变质机理为:铈添加到钢中后,尖晶石夹杂物中镁和铝不断被铈替代(含锰尖晶石夹杂物中锰优先被置换),尖晶石结构遭到破坏,从而形成CeAlO_(3)。当钢中氧含量低,相对硫含量较高时,钢中硫将参与置换反应,置换出夹杂物中的氧,因此尖晶石夹杂物和CeAlO_(3)夹杂物最终转变为Ce_(2)O_(2)S。最后通过热力学模型计算得出,将钢中尖晶石夹杂物完全改质为稀土夹杂物的最低铈含量与钢中氧含量呈线性关系,当钢中铈质量分数为氧质量分数的3倍时,即可控制钢中夹杂物为CeAlO_(3)。
Spinel-type inclusions are easy to form in the refining process of Al-killed medium manganese steel,which will deteriorate the fatigue properties of the steel and easily lead to failure of steel functions and accidents.In the current work,rare earth element Ce was used to modify spinel-type inclusions in the medium manganese steel;high-temperature simulation experiments were carried out to clarify the modification mechanism of spinel-type inclusions in medium manganese steel with Ce treatment.The results show that spinel-type inclusions were transformed into RE-containing inclusions after Ce treatment;moreover,with the decrease of T.O content,the change order of the types of RE-containing inclusions was CeAlO_(3)→CeAlO_(3)+Ce_(2)O_(2)S→Ce_(2)O_(2)S.The modification mechanism of spinel-type inclusions by Ce can be summarized as follows:after adding Ce to steel,Mg and Al in spinel-type inclusions were continuously replaced by Ce(Mg was preferentially replaced in manganese-containing spinel-type inclusions);since the structure of spinel was destroyed,CeAlO_(3)was finally formed.When the oxygen content in the steel is low and the sulfur content is relatively high,the sulfur in the steel will participate in the replacement reaction and replace the oxygen in the inclusions,resulting in the transformation of spinel-type inclusions and CeAlO_(3)inclusions into Ce_(2)O_(2)S.Finally,according to the thermodynamic model,the minimum cerium content required to completely modify the spinel-type inclusions into RE-containing inclusions is linear with the oxygen content in the steel.When the mass fraction of Cerium in steel is three times that of oxygen,the inclusion in steel can be controlled as CeAlO_(3).
作者
于哲
时训先
于成龙
YU Zhe;SHI Xunxian;YU Chenglong(China Academy of Work Safety,Beijing 100012,China;Key Laboratory of Metallurgical Industry Safety Risk Management Department,Beijing 100012,China)
出处
《工业加热》
CAS
2023年第5期1-6,共6页
Industrial Heating
基金
青年科学基金项目(41904131)
基本科研业务费项目(2022JBKY10)。
关键词
中锰钢
尖晶石夹杂物
Ce处理
夹杂物改质
medium manganese steel
spinel-type inclusions
Ce treatment
inclusion modification
