钢厂
双辊连铸无取向硅钢铸带特征及常化作用研究
双辊连铸技术是冶金及材料领域内的一项前沿技术,对于生产高品质硅钢具有独特优势.本实验研究了一种双辊铸轧w[Si]=4.5%的无取向硅钢,考察其铸态和常化处理后样品的组织、织构及析出相尺寸特征.结果表明:铸带组织以与铸带法向成5~20(°)倾角的柱状晶为主,晶内存在少量0.3~0.4μm的AlN析出相,铸带织构以λ(<001>//ND)织构为主,表层织构漫散.950℃/10 min常化处理后,析出相尺寸增大,表层λ织构增强. As an advanced technique of metallurgy and material science,twin- roll strip casting has unique advantages for producing high quality silicon steel. The present study was aimed at a 4. 5% Si non- oriented electrical steel for analyzing the structure,texture and the size of precipitates at the initial and normalized state. The results revealed that the initial structure mainly consisted of columnar grains with 5 ~ 20( °) angle to the normal of cast strip,and some AlN precipitates of 0. 3 ~ 0. 4 μ...
修正GTN模型及其在预测硅钢冷轧边裂中的应用
考虑剪应变对微孔洞损伤演化的影响,对GTN损伤模型的损伤演化机制进行修正,建立了适用于不同应力三轴度水平的损伤模型。结合隐式应力更新算法和显式有限元计算,采用VUMAT子程序实现了修正GTN模型在有限元软件ABAQUS中的数值计算。通过模拟纯剪切和剪切-拉伸两组试样的损伤演化和断裂行为,验证了修正GTN模型在不同应力三轴度承载条件下的有效性。运用修正GTN损伤模型模拟含边部缺口的带钢在轧制过程中裂纹的萌生和扩展行为,模拟结果与实验相一致,表明该模型可有效地用于带钢缺陷在轧制过程中扩展行为的分析和预测。模拟和实验结果表明,带钢边部缺口在轧制过程中,缺口前沿和后沿均会萌生裂纹,且后沿裂纹扩展更为明显。 Considering the effect of shear strain of micro-void on damage evolution, a modified GTN model applicable to various stress triaxiality conditions is proposed by modifying the damage evolution mechanism of the GTN damage model. The modified model is implemented in commercial finite element software ABAQUS by combining the implicit stress update method with an explicit finite element solving algorithm and through the user-defined material subroutine VUMAT. The damage evolution and the failure pro...
薄板坯连铸连轧流程试制含钒钛取向硅钢中氮化物析出相
通过热力学计算与模拟试验研究了含钒钛取向硅钢中氮化物析出相的析出规律与析出行为,并探讨了含钒钛元素的氮化物析出相作为薄板坯连铸连轧流程制备取向硅钢中辅助抑制剂的可行性.研究表明,在所冶炼的含钒钛取向硅钢的成分范围内,Ti N在钢液凝固末期便具备析出的热力学条件,而Al N与VN只可能在凝固后的α+γ或α+Fe3C两相区内析出.含钒钛取向硅钢中氮化物析出相以成分复杂的复合析出相为主,且随着钒钛加入量的增加,钢中抑制剂析出相总的分布密度由于含钒钛元素的氮化物析出相的增加而明显提高,使抑制剂抑制初次再结晶晶粒正常长大的能力得以加强,最终成品的磁感应强度值B8由1.857 T提升至1.898 T.同时,加入不高于0.007%的Ti与不高于0.005%的V不会影响中间脱碳退火工序的脱碳效果以及高温退火净化阶段硫、氮的脱除效果,其形成的含钒钛元素的纳米级氮化物析出相适合作为薄板坯连铸连轧流程制备取向硅钢的辅助抑制剂. The precipitation behavior of nitride precipitates in grain-oriented silicon steel containing vanadium and titanium elements produced by thin slab casting and rolling process was studied by thermodynamic calculation and simulation experiment. The feasibility of nitride precipitates containing V and Ti elements as auxiliary inhibitors was also investigated. It is found that Ti N is likely to precipitate at the final stage of solidification in the grain-oriented silicon steel,but VN and Al N can p...
加热温度对W470高硅钢连铸坯氧化铁皮的影响
采用SEM、EDS和XRD对不同加热温度下W470连铸坯氧化铁皮的微观形貌及相结构进行研究。结果表明,W470氧化铁皮难以除去的原因是氧化铁皮熔化,液相包裹着FeO,凝固时发生共晶反应,生成FeO/Fe2SiO4共晶混合物,并深嵌入基体。降低加热炉的加热温度,使连铸坯全程在FeO/Fe2SiO4共晶混合物熔点(1177℃)以下加热,可降低氧化铁皮与基体的结合力,能够有效解决W470除鳞困难问题。 The microstructure and phase structure of iron scale of W470 continuous casting billet at different heating temperatures were investigated by SEM,EDS,and XRD.The results show that the reason why the iron scale of W470 removes hardly is that iron scale is melted and the FeO is surrounded by the liquid phase,which forms FeO / Fe2SiO4eutectic mixture and is embedded into the matrix after solidification.Lowering the heating temperature and keeping the continuous casting billet heating under the melt...
表面机械研磨/异步轧制无取向硅钢薄带的渗硅行为
对w(Si)=3%无取向硅钢进行表面机械研磨处理(SMAT)和异步轧制(CSR),获得表面纳米结构,再进行550～650℃、4 h固体粉末渗硅处理,用透射电镜(TEM)、扫描电镜(SEM)和X射线衍射仪(XRD)研究表层组织演变。结果表明:经过SMAT后,w(Si)=3%无取向硅钢表面形成了等轴状、取向呈随机分布的、晶粒尺寸为10 nm的纳米晶组织;异步轧制后,表面纳米晶组织保持不变;550～650℃、4 h渗硅处理后,SMAT+CSR样品表面形成化合物层,其厚度随着温度的升高由17μm增加到52μm;化合物层由Fe3Si和FeSi相组成. Nanostructured surface layer was fabricated on a 3%(mass fraction) non-grain oriented silicon steel by means of surface mechanical attrition treatment(SMAT) and cross-shear rolling(CSR),and then a solid powder siliconizing treatment was carried out for the SMAT+CSR sample at 550~650 ℃ for 4 h.The microstructural evolution was examined by using transmission electron microscopy(TEM),scanning electron microscopy(SEM) and X-ray diffraction(XRD).Experimental results show that: equiaxed nanocrystallin...
日本取向电工钢生产工艺最新研发进展
根据相关的取向电工钢典型专利技术,概述了日本高磁感低铁损取向电工钢低温板坯加热、抑制剂合理调节、关键成分Mn、C、Sn和Sb调节与利用、新型退火剂和绝缘溶液的制备及细化磁畴等生产工艺最新动态和进展情况,并提出了国内企业申请取向电工钢专利时应当借鉴之处。 According to related typical patent technology for grain-oriented electrical steel sheets,the recent trends and progress situation for production process of grain-oriented electrical steel sheets with high magnetic flux density and low core loss in Japan are summarized including low temperature slab heating,suitably regulating inhibitors,adjusting and utilizing key element Mn,C,Sn and Sb,manufacturing for new annealing agent and insulating solutions,and fining magnetic domain,and some suggestion...
低温取向硅钢热轧析出物与织构的研究
采用低温板坯加热制备取向硅钢,通过透射电镜(TEM)观察并研究热轧板中的析出物,用ODF织构法研究热轧板距表面1/8、1/4和1/2处的织构分布。结果表明,热轧板中的析出物主要是密排六方AlN,AlN形貌呈规则长方形,AlN颗粒大小不等,分布密度低;热轧板中的织构沿板厚方向,由亚表层的{110}<001>织构向1/2中心层的α线织构变化,其中{110}<001>织构在热轧板距表面1/4层处最强。 The low temperature grain-oriented silicon steels were produced by acquired inhibitor method.The precipitates in hot rolling strip were observed and studied by transmission electron microscope,and the texture distribution in 1/8,1/4 and 1/2 layers of hot rolling strip were analyzed by ODF method.The results showed that the square shaped h-AlN is the main precipitates in hot rolling strip.The precipitates are varying in size and distribution.The texture of hot rolling strip in thick direction are...
