钢厂
双辊连铸3%Si无取向硅钢铸带特征
针对传统工艺生产硅钢周期长、能耗大等缺点,采用双辊连铸工艺制备3%Si无取向硅钢连铸薄带,利用MEM,SEM和TEM观察了铸带的组织、织构及析出物,同时对比了Al的质量分数为0.6%和0.9%的连铸薄带在组织、织构及析出物特征方面的异同.结果表明:双辊连铸工艺生产的3%Si无取向硅钢铸带的组织为均匀等轴晶粒,平均晶粒尺寸约为300μm;织构组成随Al质量分数的不同具有明显差别,Al质量分数为0.9%的铸带中{100}织构强度是随机织构的7倍;铸带中的析出物为AlN和MnS,最大尺寸分别为500和50 nm左右. Given the lengthy production cycle,high energy consumption,and other shortcomings of the traditional process for producing silicon steel,a twin-roll casting process was used to produce 3%Si non-oriented silicon steel casting strips. MEM,SEM,and TEM were used to compare micro-structure,texture,and precipitate characteristics of a casting strip containing 0.6%Al with another containing 0.9%Al.The structure of 3%Si non-oriented silicon steel produced by the twin-roll casting process was a uniform i...
RH精炼工艺对无取向硅钢MgO·Al_2O_3夹杂物演变影响及控制
基于BOF→RH→CSP生产工艺,研究了RH精炼过程钢中夹杂物类型演变及MgO·Al2O3夹杂物形成规律,同时对MgO·Al2O3夹杂物的形成条件进行了热力学计算,借助CFD数值模拟软件研究了RH精炼过程卷渣行为。研究发现,RH精炼过程20和30 min时,w([MgO])/w([Al2O3])为0.005~0.020,未发现MgO·Al2O3夹杂物;RH出站后夹杂物w([MgO])/w([Al2O3])为0.3~0.5,且RH精炼结束后MgO·Al2O3夹杂物占夹杂物总量的58.4%;另外,RH精炼过程钢液表面速度CFD模拟结果为0.57 m/s,大于临界卷渣速度0.45 m/s,且顶渣成分与夹杂物成分相近,存在卷渣现象。热力学计算表明,钢液与炉渣平衡时钢中w([Al])为0.31%~0.37%,w([Mg])为0.00024%~0.00028%,在MgO·Al2O3生成区域之内。减少RH处理过程卷渣,浇铸过程下渣及控制顶渣和包衬相中MgO质量分数可抑制MgO·Al2O3夹杂物形成。 Based on the practical production of non-oriented silicon steel, the evolution of inclusion type and the formation of MgO·Al2O3inclusion were analyzed in the process of BOF→RH→CSP. The thermodynamic conditions for forming MgO·Al2O3inclusion were discussed and the behavior of slag entrapment of molten steel was also simulated by CFD software during RH refining. The results showed that the value of w([MgO])/w([Al2O3]) was in the range of 0.005-0.020 and no MgO · Al2O3 inclusion was observed at 20 ...
凝固速率对定向凝固50W600无取向硅钢固液界面稳定性和枝晶间距的影响
采用ZMLMC超高梯度定向凝固装置,研究了5种凝固速率(10、35、80、150和450μm/s)对定向凝固50W600无取向硅钢的固液界面稳定性转变规律和一次、二次枝晶间距的影响。研究结果表明,在特定的温度梯度下,随着凝固速率的增加,定向凝固的固液界面由胞状晶转变为胞状枝晶,再转变为细小的树枝晶。随着凝固速率的增加,定向凝固组织的枝晶形貌逐渐细化,一次和二次枝晶间距逐渐减小,且与冷却速率之间都符合指数关系:λ1=151.73×(G L·R)-0.31,λ2=22.07×(G L·R)-0.44。当冷却速率达到4.275℃/s时,一次、二次枝晶间距分别为112μm、14.1μm。 Under the conditions of certain temperature gradient and different solidification rate,the directional solidification experiment of non-oriented electrical steel 50W600 was carried out.The microstructure of 50W600 steel was also analyzed in different solidification rate.The result shows that the solid/liquid interface of the steel undergoes an evolution from cellular,cellular dendrite and finally to fine dendrite morphologies.The dendrite refines gradually and the distance between dendrites decr...
电工钢中柱状晶热压缩时取向的变化及对析出的影响
利用电子背散射衍射(EBSD)技术和场发射电子扫描显微镜(FESEM)研究了电工钢中柱状晶不同初始取向50%热压缩变形后的演变规律及其对粒子析出行为的影响。结果表明:〈100〉晶粒形变后仍为〈100〉取向,只发生绕ND∥〈100〉方向的转动,具有遗传性,粒子析出数量少。柱状晶长轴与压缩轴的偏转度增加,取向的稳定性变差,超过40°,可形成〈111〉取向,期间发生复杂的滑移系交互作用,产生较高的缺陷密度,促进粒子析出。MnS粒子主要在晶内析出,变形温度高、形变量低,粒子均无法充分析出。回复时,形变晶粒内高的储能和缺陷密度是促进粒子进一步析出的必要条件。 The evolution of initial orientations and their influence on precipitation of columnar-grained electrical steel after 50% hot compression deformation were investigated by electron backscatter diffraction technique and field emission scanning electron microscopy.The results indicate that the〈100〉orientated columnar grains remain still〈100〉after hot compression deformation,with only rotation around ND parallel to〈100〉direction,with heredity,and less precipitation.As the deviation angle between the...
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...
无取向硅钢冶炼过程中的夹杂物遗传变化
研究表明,硅钢中的夹杂物对成品带钢的磁性能有显著影响。为研究冶炼过程硅钢中的夹杂物遗传变化,进而提出更有效的控制措施加以去除,本文结合典型的无取向硅钢生产炉次,采用非水溶液电解提取+扫描电镜观察方法分析冶炼过程中上述炉次典型试样的夹杂物。结果表明:转炉冶炼结束、RH精炼开始时,钢的氧化物夹杂总量最大,约为0.23%;RH精炼过程中,氧化物夹杂总量不断降低,并在脱碳结束时达到最低,约为0.02%;连铸过程中,氧化物夹杂总量仍有不断降低趋势,但夹杂物的平均尺寸变化不大。本试验条件下,中间包试样的夹杂物数量约为1.59×104个/mm3。 As we all know, the non-metallic inclusion effects magnetic properties of silicon steel sheets obviously. The article aims to study the heredity of non-metallic inclusion in non-oriented silicon steels during the steel making process, and then provides a more effective controlling measure to remove the inclusions. Based on the typical non-oriented silicon steel charges, the non-aqueous solution extraction and SEM observation were adopted to analyze the non-metallic inclusions. Results show that,...
国产化高牌号无取向硅钢退火、涂层炉新技术
从影响高牌号无取向硅钢退火工艺的主要参数入手,介绍高牌号无取向硅钢退火炉在加热、气氛控制、冷却、涂层烘烤方面的新技术,并展望无取向硅钢退火炉的发展方向。 Based on the technology parameters of high-grade non-oriented silicon steel annealing,the new technology of the annealing line,which includes heating,atmosphere control,cooling,coating baking,is introduced,and the development direction of non-oriented silicon steel annealing furnace is pointed out.
硅钢常化炉段工艺特征及问题分析
连续酸洗退火机组(CPAL)对于当前生产高磁感取向硅钢和高牌号无取向硅钢是必不可少的一个环节。常化炉是常化酸洗机组关键的组成部分。本文对国内自主建造的两条退火酸洗机组的工艺流程,特别是常化炉段进行了对比分析。总结出了常化炉的工艺及组成特点,对生产过程中暴露的问题进行了仔细的分析并提出了改进的意见,对于以后新建常化炉具有一定的提示作用。 The continous pickling annealing line(CPAL) is an essential step in producing high magnetic induction grain-oriented silicon steel and high grade non-oriented silicon steel.The normalizing furnace is a very important part of the CAPL.In this paper,the process flows of two CAPL with independent manufacture in our country have been compared,especially the part of normalizing furnaces.The characteristics of process and component are summarized and problems of the normalizing furnace during the prod...
