钢厂
无取向电工钢孔洞缺陷控制实践
针对马钢无取向电工钢孔洞缺陷的分布规律及形貌特征,对缺陷样进行了显微分析,并利用生产实绩数据分析了该缺陷产生的原因。结合热轧生产过程,主要通过避免带钢撞击导卫以及降低导卫结瘤的产生等措施,可有效抑制热卷异物压入产生,从而降低冷轧工序孔洞的产生。 In viewing of the distribution and morphology characteristics of the hole defect of non-oriented electrical steel in Maanshan Iron and Steel Co.,Ltd.,the causes of the defect were analyzed by micro analysis of the defect sample and the production data.Combined with the production process of hot rolling,by avoiding the impact of strip steel on the guide and reducing the nodule formation on the guide,the pressing of foreign bodies in hot coiling could be effectively suppressed,thus reducing the fo...
电工钢铸锭内析出相粒子特征及回溶行为
利用场发射电镜及能谱仪研究了取向电工钢薄、厚板坯铸锭中不同区域的析出相差异,确定了MnS、AlN及Fe3C的析出顺序和形貌特征。结果表明AlN以先析出的MnS为形核核心,形成粗大微米级的复合析出相。针状Fe3C既可以在复合析出相表面形成也可以在基体中单独出现,主要受冷却速度的影响。在1250℃保温1~2 h,AlN、Fe3C均可完全回溶,但部分MnS仍不回溶。MnS尺寸随着保温时间延长而增大。导致热轧板中沿轧向分布的粗大MnS,减弱了粒子钉扎力。 Precipitates in thin and thick slabs of electrical silicon steel were investigated by means of field emission SEM and EDS analysis.The precipitation sequence and the morphology of MnS,AlN and Fe3C particles were identified.AlN particles are observed to be nucleated on surface of MnS forming micron-meter-sized complex particles.Acicular Fe3C can precipitate on surface of the complex MnS/AlN particles or directly from matrix depending on cooling rate of the slabs.After holding at 1250 ℃ for 1-2 h,...
国外采用板坯低温加热工艺生产Hi-B取向电工钢最新进展
根据新日铁、JFE及浦项等国外钢铁公司2008年以来在日本专利局、欧洲专利局(EP)及世界知识产权组织(WIPO)申请公开的有关生产Hi-B取向电工钢典型专利技术,概述了近年来国外大型钢铁企业采用低温板坯加热(坯加热温度<1 280℃)技术生产Hi-B取向电工钢主要技术重点,即将调节关键化学成分Al、N、Sn及Sb等与工艺改进相结合。最后介绍了国外大型钢铁企业采用低温板坯加热技术生产Hi-B取向电工钢实例。 The latest developments on technology for manufacturing Hi-B grain oriented electrical steel sheets developed by Nippon Steel Corp.,JFE Steel and POSCO were described according to the patents published by World Intellectual Property Organization,Japan Patent Office and European Patent Office over the recent years.The low temperature slab heating process(particularly slab-heating temperature<1 280 ℃) together with suitably adjusting key chemical elements such as Al,N,Sn and Sb elements was the...
CSP流程热轧板常化温度对冷轧无取向电工钢退火组织和磁性能的影响
研究了CSP工艺生产≤0.005%C-1.1%Si的2.2mm无取向电工钢热轧板在800~1000℃常化对0.5mm冷轧板840℃退火后组织和磁性能的影响。结果表明,热轧板常化温度升高,冷轧板退火后的再结晶晶粒增大,铁损降低,磁感增加;热轧板常化温度超过900℃,因第二相固溶而后弥散析出,退火后冷轧晶粒细化,铁损增加,因此该无取向电工钢热轧板最佳常化温度为900℃。 The effect of normalizing at 800-1000℃ of CSP produced plate(≤0.005%C-1.1%Si) on the microstructure and magnetic properties of downstream cold-rolled non-oriented electrical steel annealed at 840℃ was studied.Results show that with increasing normalizing temperature of hot-rolled material the recrystallized grain size of annealed sheet increases,iron loss reduced and magnetic induction increases.As normalizing temperature excesses 900℃,grain is refined and iron loss increases after annealing due...
无取向硅钢钢液增钛原因分析
对无取向硅钢炼钢全流程钢液增钛的原因进行了分析,认为铁水钛含量、转炉出钢温度、转炉下渣量、精炼渣TiO2含量、钢水罐及RH浸入管混钢种生产是影响钢液增钛的主要原因。通过采取低钛铁水冶炼,减少转炉下渣量,提高出钢温度,添加白灰改质精炼渣等措施,均能够降低钢液中的钛含量。 After analyzing the causes leading to increased content of titanium in molten nonoriented silicon steel during whole steelmaking process, it was concluded that such factors as content of titanium in hot metal, tapping temperature from converter, quantity of roughing slag entered into the ladle from converter, content of TiO2 in refining slag, molten steel ladle car,carrying out the steelmaking of different steel grades by the same ladle and same RH immersion tube were the main causes ...
热轧工艺对TSCR流程生产取向硅钢组织和性能的影响
取向硅钢热轧板中组织、织构梯度对发展完善的二次再结晶十分关键,通过对2种不同热轧工艺生产取向硅钢的组织、织构进行研究,结果表明:采用后道次大压下热轧工艺时热轧板表层再结区晶粒平均尺寸增加,再结晶区厚度增加,高温退火后二次晶粒尺寸减小;采用后道次大压下热轧工艺热轧时,热轧板中平均等效应变高,热轧板厚度心部{100}〈011〉和{100}〈001〉位向取向强度降低,({111}~{113})〈110〉位向取向强度提高,高温退火后{110}〈001〉位向偏离角降低,磁性能提高。 The texture and microstructure gradient in hot rolled grain oriented silicon steel strip was one of the essential factors to achieve a perfect secondary recrystallization.The texture and microstructure of grain oriented silicon steel strip as-rolled with two different hot rolling parameters was investigated.The results show that with big reduction at the end rolling process,the intensity of {100}〈011〉 and {100}〈001〉 orientation reduces with({111}-{113})〈110〉 orientation intensity enhanced in hot...
在动态热处理条件下对取向电工钢二次再结晶的研究
对应用动态加热进行短时温度退火的取向电工钢进行了二次再结晶研究。所进行研究的实验用取向电工钢是经过终冷轧和后续罩式退火后的一条工业化生产线生产的。研究结果表明,运用短时热处理条件可引起研究钢完全的异常晶粒长大。在实验室处理的材料的织构和金相组织与工业化生产的经过终退火而获得的相同的取向电工钢类似。但是,在实验室处理的取向电工钢的二次再结晶的矩阵中可观测到\"寄生\"晶粒。从磁性观点看,这些\"寄生\"晶粒含有不理想的{111}取向织构。 The present study was made to investigate secondary recrystallization in grain-oriented steels annealed at short time temperature exposures with application of dynamical heating.The investigated GO(Grain Oriented) steels for experiments were taken from one industrial line after final cold rolling reduction and subsequent box annealing.It was shown that application of short time heat treatment conditions could lead to complete abnormal grain growth in the investigated GO steel.The texture and mic...
二次冷轧法与三次冷轧法制备取向硅钢薄带的织构转变规律
本文以热轧常化板为初始材料,采用二次冷轧法与三次冷轧法制备了0.1 mm厚的取向硅钢薄带,测定相应的磁性能,并通过EBSD取向成像技术检测了二次冷轧法与三次冷轧法各工艺过程中织构与组织演变规律。结果表明,采用最终冷轧压下率适中的三次冷轧法,能在冷轧至0.1 mm时保存较多的高斯晶核,使得高温退火后的磁性能明显优于二次冷轧法。最终冷轧压下率通过影响脱碳退火后样品中的{111}<112>织构组分及Goss晶粒数量对最终二次再结晶产生重要影响。 Grain-oriented silicon steel sheets with a thickness of 0. 1 mm were produced from hot-rolled and normalized sheets by two-step-rolling and three-step-rolling methods. Their magnetic properties were measured,and the textures were detected by EBSD technique. The results show that the three-step-rolling method,which has a moderate reduction rate of final cold rolling,can maintain more { 110} < 001 >nucleus,and thus obtaining better magnetic properties compared with the two-step-method. The f...
辉光放电发射光谱法测定电工钢中8种元素
通过对辉光放电发射光谱法分析电工钢样品光谱行为的研究,分析其工作参数如:电压、电流、预溅射时间和积分时间对光谱强度和稳定性的影响,并以铁为内标元素,优化了工作参数。确定了直流辉光放电光谱法测定电工钢中碳、硅、锰、磷、硫、铬、镍、铜共8种元素的定量分析方法,并对该方法分析的精密度和准确度进行验证,结果表明,各元素的测定结果与认定值和其他方法测定值一致,测量元素结果RSD值小于2%。 Based on research on analyzing the spectrum behavior of the sample taken from the electrical steel by glow discharge optical emission spectrometry,the effect of its operational parameters such as current,voltage,pre-sputtering time and integrating time on the spectral intensity and spectral stability is analyzed.Taking the Fe as an element applied by internal standard method,these operational parameters are optimized,and therefore the quantitative analysis method for testing eight kinds of eleme...
冷轧无取向硅钢横向厚差控制
冷轧中中低牌号的无取向硅钢多采用万能凸度轧机(Universal crown mill,UCM)生产,其板形好坏受制于UCM轧机板形调节手段的协调使用。为掌握UCM轧机的板形控制特点,建立基于二维变厚度有限元的辊系弹性变形和基于三维差分的轧件塑性变形的六辊轧机耦合模型,对UCM轧机的板形调控性能进行详尽的分析,包括工作辊和中间辊弯辊、中间辊窜辊的调控功效、辊间接触压力分布等。在此基础上,提出可用指导生产的板形控制策略,指出UCM轧机在横向厚差控制方面的不足。针对工业生产中UCM轧机轧制无取向硅钢横向厚差大的问题,在大量仿真计算的基础上,开发具有高次曲线函数的边部变凸度(Edge variable crown,EVC)的工作辊。采用该工作辊后,各种品种的无取向硅钢的横向厚差不大于10μm的百分比由24%提高到99%,横向厚差的均值小于6μm,远小于之前的13μm。 Medium-low grade non-oriented silicon steel is rolled often by universal crown mill(UCM) during cold rolling.Its shape quality is dependent on the coordinated control of several shape adjustment devices of UCM.In order to understand the shape control characteristics of UCM,coupling model of six-high rolling mill,based on two-dimensional varying thickness finite element rolls elastic deformation model and three-dimensional finite difference strip plastic deformation model,is setup for the detaile...

