电渣重熔过程中渣系对NiCrMoV合金钢电渣锭洁净度的影响  

Effect of Slag System on the Cleanliness of Electroslag Ingots during Electroslag Remelting of NiCrMoV Alloy Steel

作　　者：李健[1] 凌海涛 柴锋[1] 罗小兵[1] 常立忠 Li Jian;Ling Haitao;Chai Feng;Luo Xiaobing;Chang Lizhong(Division of Engineering Steel,Central Iron and Steel Research Institute,Beijing 100081,China;School of Metallurgical Engineering,Anhui University of Technology,Ma’anshan 243002,China)

机构地区：[1]钢铁研究总院工程用钢研究所,北京100081 [2]安徽工业大学冶金工程学院,马鞍山243002

出　　处：《特殊钢》2023年第4期35-42,共8页Special Steel

基　　金：国家自然科学基金(52274312);安徽省高校自然科学研究项目(KJ2021A0396)。

摘　　要：针对NiCrMoV合金钢电渣重熔过程中Ti元素的烧损严重问题,通过实验室实验和热力学计算研究了不同渣系对电渣锭化学成分及夹杂物数量、成分和尺寸分布的影响规律。结果表明,电渣重熔后电渣锭中总氧含量明显增加,由自耗电极的15.1×10^(-6)增加至(31.3~42.1)×10^(-6),夹杂物数密度增加至6.54~15.95个/mm^(2),而氮含量变化不大;采用渣系70%CaF_(2)-30%Al_(2)O_(3)和55%CaF_(2)-25%Al_(2)O_(3)-17%CaO-3%MgO时,电渣锭中Ti元素的烧损严重,夹杂物以Al_(2)O_(3)为主,渣相中添加一定量的TiO_(2)能较好地控制重熔后Ti的烧损,夹杂物类型主要由Al_(2)O_(3)、Al_(2)O_(3)-CaOTiO_(2)、其他氧化物夹杂组成,且夹杂物中TiO2含量明显增加;通过热力学计算,揭示了渣相中添加TiO2对稳定电渣锭中Ti元素含量的作用机理;综合考虑重熔后电渣锭的洁净度水平,确定了合适的电渣重熔渣相成分(50%CaF_(2)-25%Al_(2)O_(3)-17%CaO-_(3)%MgO-5%TiO_(2))。In order to control the serious loss of Ti element during electroslag remelting of NiCrMoV alloy steel,the effect law of different slag systems on the chemical composition of ESR ingot,the number,composition,and size distribution of inclusions in electroslag ingots were investigated through laboratory experiments and thermodynamic calculation.The re-sults showed that the content of totaloxygen in ESRingots obviouslyincreased after electroslag remeling and it wasin-creased from 15.1×10^(-6)in consumable electrode to(31.3~42.1)×10^(-6)°in ESR ingots.The number density of inclusions was increased to 6.54-15.95 PCS/mm^(2):However,the content of nitrogen was almost unchanged.When the slag systems 70%CaF_(2)-30%Al_(2)O_(3)and 55%CaF_(2)-25%Al0_(3)-17%Ca0-3%Mg0 were adopted,the Ti loss in ESR ingots became serious and the inclusions were mainly Al_(2)O_(3).Furthermore,the Ti loss in ESR ingots could be controlled when a certain amount of TiO_(2)was added to the slag.The types of inclusions were mainly composed of Al_(2)O_(3),AlO-Cao-TiO_(2),and other oxides.The content of TiO_(2)in inclusions was obviously increased.Besides,the mechanism of stabilizing Ti content in ESR ingots by adding TiO_(2)to the slag was revealed through thermodynamic calculation.Based on the cleanliness of ESR ingots after electroslag remelting,the composition of the appropriate slag system(50%CaF,-25%Al_(2)O_(3)-17%Ca0-3%Mg0-5%Ti0_(2))was determined.

关 键 词：NiCrMoV合金钢 电渣重熔 渣系 洁净度 热力学计算 

分 类 号：TF744[冶金工程—钢铁冶金]