钢厂
无取向电工钢边部减薄控制技术研究
叠片系数是冷轧无取向电工钢的重要质量指标。为了提高叠片系数,必须保证无取向电工钢板形良好以及横向厚差小。针对攀钢冷轧厂4机架HC轧机轧制无取向电工钢的边部减薄问题,以无取向电工钢横向厚差最小作为目标函数,建立了一套针对无取向电工钢边部减薄控制的辊型曲线优化数学模型,开发了无取向电工钢专用辊型曲线,使无取向电工钢横向厚差从25μm降低到10μm以下,取得了良好的控制效果。 The lamination factor is an important quality index of non-oriented silicon steel strip.Considering the lamination factor,the non-oriented silicon steel must have a good shape and a smaller transverse thickness difference.In order to solve the edge thinning of non-oriented silicon steel strip in Panzhihua Steel,a mathematic model for designing the roll shape is built.In the model,the transverse thickness difference of non-oriented silicon steel strip is taken as the objective function.Based on t...
取向硅钢用特种氧化镁的应用研究
采用XRD、SEM和激光粒度仪等手段,观察并研究了不同特性氧化镁在硅钢表面形成硅酸镁底层形貌特点,并结合热力学和差热-失重分析了MgO-SiO2的反应机理。研究结果表明:粒度小,活性值高的特种氧化镁在高温退火过程中与基体表面氧化物生成的硅酸镁底层,界面中硅酸镁底层嵌入基体较多,表面致密,颗粒细小,有利于形成附着性能优良的硅酸镁底层。 Surface microstructure of Mg2SiO4 coatings formed on the surface of oriented silicon steel coated with different kinds of MgO was investigated by XRD and SEM.The reaction mechanism between MgO and SiO2 was analyzed by TG-DSC and thermodynamic calculation.Results revealed that when the MgO with finer microstructure size and higher activity is employed,a dense Mg2SiO4 layer with finer microstructure and good binding to the steel substrate can be obtained.The results are very helpful for the prepar...
电工钢中柱状晶尺寸及退火工艺对{100}织构的影响
利用EBSD技术研究了电工钢中不同的柱状晶尺寸及退火工艺下{100}织构的演变规律。结果表明,初始晶粒尺寸的影响最显著。细小柱状晶热轧后经过常化处理,组织已均匀,但中心层有强{100}织构。粗大柱状晶中{100}织构的遗传性强,常化及中间退火后,中心层仍有粗大的以{100}取向为主的晶粒;脱碳退火后才能完成组织均匀化和织构梯度的弱化。常化时的升温速度也对织构演变存在影响,低的升温速度有利于{100}织构的保留,但升温速度的影响没有初始晶粒尺寸及退火次数的影响显著。细小柱状晶样品经过热轧及三次退火工艺适合制备取向电工钢。 Evolution of {100} texture of different columnar grains and annealing process was investigated in electrical steels with the help of EBSD technique.The results show that the effect of initial grain size is the strongest.The initial fine-grained specimen shows uniform microstructure after the normalizing process,while {100} grains appear preferentially in the central layer of sheets.The heredity of {100} texture in the initial coarse-grained specimen is more significant.{100} mainly-oriented coar...
一类非线性系统控制方法在硅钢生产上的应用
硅钢工业退火炉温度控制具有强耦合、纯滞后、多扰动等特点,它的控制方法代表着一类非线性系统控制的解决方法。以硅钢工业退火炉温度为控制对象,在双交叉限幅控制的基础上引入了智能学习系统,形成了基于智能学习系统的双交叉限幅控制方法来解决此类非线性系统的控制问题,并通过模块化的编程来实现其功能。结果表明:与传统的PID控制相比,该控制方法的控制精度、抗扰性等控制指标有明显提高,是解决此类非线性控制的一种有效方法。 The temperature control of silicon steel industrial annealing furnace has the features of strong coupling,pure lag,multidisturbance. The control method represents the solution of a class of nonlinear control systems. The control object is the temperature control of silicon steel industrial an-nealing furnace, the intelligent learning system based on Double Across Limit Control is introducedand used to solve control problem of this kind of nonlinear system, and the module programming isused to re...
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...
奥氏体化温度对高碳含硅钢等温转变的影响
采用XRD物相分析、金相组织观察及TEM精细组织分析研究了奥氏体组织结构状态对Fe-0.88C-1.35Si-1.03Cr-0.43Mn钢中温等温相变鼻温和孕育期的影响,以及不同温度奥氏体化后240℃等温20 min试样的组织结构特征。试验发现,随着奥氏体化温度的升高,中温等温开始转变的鼻温移向更低温度并且相变孕育期缩短;不同温度奥氏体化后同为240℃等温20 min处理,虽然均形成由贝氏体铁素体亚条平行排列构成的束状贝氏体组织,但贝氏体组织的精细结构状态不同,突出的差别在于对应低温奥氏体化贝氏体亚条端部边界具有凸起结构,而对应高温奥氏体化贝氏体亚条端部边界较为平齐且呈现楔形结构。不能简单地以马氏体切变机制认识试验钢中贝氏体组织的形成。 The influence of austenitization temperature on the incubation period and the bainitic phase transformation behaviour in high-carbon silicon steel has been investigated using X-ray diffraction(XRD), optical microscopy and transmission electron microscopy(TEM). The microstructure characteristics of the isothermal transformation(240 ℃, 20 min)products were also studied. It was found that the nose temperature of bainite transformation and incubation period decreased with the increasing austenitizin...
薄带连铸取向硅钢的热轧孪生行为
薄带连铸流程下取向硅钢粗大λ晶粒(〈100〉//ND,normal direction)的“遗传”会导致磁性能恶化.为解决这一问题,针对取向硅钢的热轧孪生行为开展研究,结果表明:凝固组织粗大的取向硅钢在650℃热轧时可产生大量{112}〈111〉形变孪晶,这与具有高层错能的硅钢在较高温度下难以孪生变形的传统认知不同.热轧过程中复杂的应力状态降低了变形孪晶的取向依赖性,由于具有更高的储存能,孪晶界/孪晶界及孪晶界/晶界交叉点成为再结晶形核的优先位置,大大提高了常化过程中的再结晶率,受沿孪晶界应变分布及孪晶间距离的限制,沿孪晶界形核的再结晶晶粒通常呈“饼状”,最终形成以细小且取向漫散的再结晶晶粒为主的常化组织,消除了初始凝固组织中有害的粗大λ晶粒. In strip casting grain-oriented silicon steels, the inheritance of coarse λ grains(〈100〉//ND, normal direction) can deteriorate their magnetic properties. To solve the problem, twinning behaviors in strip casting grain-oriented silicon steels during hot rolling were investigated in this work. It is found that after rolling at 650 ℃, a number of {112}〈111〉deformation twins are formed in the coarse solidification microstructure of the steels, in contrast to the well-accepted view that it is diffic...
硅钢级氧化镁的研究进展
随着中国电工钢产量的增加,硅钢级氧化镁需求量不断增加,传统的以白云石为原料制备氧化镁的工艺已经无法满足市场需求。中国是一个卤水资源丰富的国家,因此,研究如何资源化综合利用盐湖资源变得越来越重要。硅钢级氧化镁是一种制备取向硅钢的涂层材料,主要用于取向硅钢高温退火处理阶段,起到隔离剂、绝缘膜层、脱硫、脱磷等作用。综述了制备硅钢级氧化镁的方法、工艺流程、研究进展及存在的问题,指出了硅钢级氧化镁制备技术的发展方向,并对中国卤水资源的利用提出了建议。 With the increasing output of electric steel,the demand for silicon steel grade magnesium oxide(MgO) is larger and larger in China,and the traditional MgO production process with dolomite as raw material has been unable to meet market demand.China is a brine resource-rich country,the study of how to comprehensively utilize salt lake resources has become increasingly important.As a coating material used for preparing oriented silicon steel,silicon steel grade MgO is mainly used in the process of ...
电工钢生产中硫的控制
针对攀钢高硫铁水冶炼现状,结合不同生产工艺路线,论述了攀钢近年来为实现低硫电工钢的生产,在铁水预处理、转炉冶炼、钢水精炼过程中硫控制技术的开发与应用,形成了低硫洁净钢生产工艺技术,实现了低硫电工钢的生产。低硫电工钢RH脱硫率可达到20%左右,成品[S]控制在0.006%左右。 According to the smelting situations of hot metal with high sulphur content at Panzhihua Steel,combined with different produce processes,technologies for controlling the sulfur content during hot metal pretreatment,converter smelting,and second refining are developed. Technologies in low-sulfur clean steelmaking are formed. Low-sulfur electric steel are produced. As for the desulfurization rate of lowsulfur electric steel can reach about 20%,and the content of [S] in products is controlled to ab...
无取向电工钢硫含量控制技术研究
针对采用含钒铁水生产无取向电工钢存在的铁水脱硫率低、转炉冶炼过程回硫量大、成品硫含量偏高的问题,通过对含钒钛铁水脱硫,减少转炉冶炼过程回硫以及RH脱硫技术等方面的研究,大幅度降低了电工钢成品硫含量。生产表明钢中w(S)=0.001 9%~0.006 9%,平均为0.004 2%;w(S)≤0.008%的比例达到了100%,且w(S)≤0.005%的比例也达到了91.43%。 In cognizance of the problems of low desulphurization rate for hot metal,large sulfur-recovery in converter as well as high sulfur content in products in producing non-orientation electrical steel with vanadium-content hot metal countermeasures have been carried out.Sulfur content in non-orientation electrical steel is decreased obviously by way of study on technologies of desulphurization for hot metal with vanadium & titanium,sulfur-recovery control in converter and desulphurization in RH ...

