钢厂
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 ...
无取向硅钢晶粒长大过程中应力对织构和晶界变化的影响
采用EBSD技术研究了有、无拉应力作用下无取向硅钢在晶粒长大过程中织构转变及晶界变化的规律。结果表明:在晶粒生长期间,无应力作用下的硅钢中,{111}〈112〉,{111}〈110〉织构组分强化,而{100}〈001〉织构组分弱化;与无拉应力作用下的情况相比,施加5MPa的拉应力时,{111}〈112〉,{111}〈110〉织构组分强化的速率下降,{100}〈001〉织构组分变化不明显。对于在晶粒生长期间持续变化的{111}〈112〉,{111}〈110〉和{100}〈001〉织构组分而言,虽然有、无拉应力作用下硅钢的{111}〈112〉和{111}〈110〉织构组分的高取向差角度晶界频率均下降,而{100}〈001〉织构组分的高取向差角度晶界频率则上升,但当有拉应力作用后,{111}〈112〉和{111}〈110〉织构组分的高取向差角度晶界频率下降的速率变小,{100}〈001〉织构组分的高取向差角度晶界频率上升的速率稍有变小。通过对无取向硅钢在晶粒长大过程中织构转变及晶界变化规律的研究,分析了合金原子在晶界的偏聚行为。 The rules of texture and grain boundary transformation in the nonoriented silicon steel under applied stress or without applied stress during grain growth were investigated by EBSD.The results show that the {111}〈112〉 and {111}〈110〉 components in the nonoriented silicon steel without stress are strengthened during grain growth whereas {100}〈001〉 component is weakened,but the growth rate of {111}〈112〉 and {111}〈110〉 component decreases,while the area fraction of {100}〈001〉 component doesn’t chang...
水氯镁石制备硅钢级氧化镁
以水氯镁石为原料,采用氨法沉镁-煅烧-添加剂的方法制备硅钢级氧化镁。考察了反应温度、反应pH值、陈化时间对中间体氢氧化镁纯度及转化率的影响;研究了煅烧温度和煅烧时间对氧化镁水化率的影响及添加剂的量对氧化镁悬浮性能的影响。控制实验条件为:反应温度55℃,pH值为9.5,陈化时间2h,煅烧温度1050℃,煅烧时间2h,添加剂量为0.8%,制得氧化镁的纯度为98.99%、水化率为2.92%、悬浮性能为3mm/h,达到硅钢级氧化镁的要求。 Using bischofite as raw material,the preparation of magnesium oxide with silico-steel grade was studied.The effects of reaction temperature,reaction pH value and aging time on the intermediate magnesium hydroxide purity and conversion rate were studied.Calcinations temperature,calcinations time relationship to the hydration rate of MgO and amount of additive to the suspension performance of MgO were investigated.The results indicated that the optimum technological conditions were as follows:reac...
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...
常化冷却工艺对低温取向硅钢组织及析出相的影响(英文)
利用OM、TEM与EDS技术,对Fe-3.2%Si低温取向硅钢热轧板进行不同常化冷却工艺处理后的显微组织、析出相及最终产品的磁性能进行分析,并与热轧板的组织和析出相进行对比。结果表明,常化板较热轧板的表层组织均匀,基体中再结晶比例增加,带状组织变窄;常化板中析出物的数量明显比热轧板的多,析出物主要有AlN、MnS及复合析出的(Cu,Mn)S等。在常化温度1120℃、保温3 min的条件下,采用二段式冷却较空冷、淬沸水、淬常温水的冷却工艺,常化板表层显微组织更均匀,沿板厚方向的显微组织的不均匀性显著,取向硅钢的磁性能最高;常化后采用二段式冷却工艺析出的细小析出物数量最多,且弥散分布在基体中,抑制剂的抑制效果最好,对成品获得高磁性最有利。 Microstructure, precipitate and magnetic characteristic of final products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared with the hot-rolled plate by optical microscopy(OM), transmission electron microscopy(TEM), and energy dispersive spectrometry(EDS). The results show that, the surface microstructure is uniform, the proportion of recrystallization in matrix increases, and the banding textures are nar...
D21硅钢芯片冲压工艺分析及模具设计
变压器D21硅钢铁芯片采用冲压工艺生产。首先对其工艺进行了分析,确定了冲压方案。对产品进行了排样设计,计算了冲压力,确定了压力中心。然后,设计了单工序落料模具,完成了模具装配图。 D21 silicon steel chips for transformer are produced by stamping.First,its stamping process was analyzed and the scheme of the stamping process was determined.The product layout was designed,the punching pressure was calculated,the pressure center was determined.Then,the blanking die with single procedure was designed,the die assembly drawing was completed.
二次冷轧法对薄带连铸无取向高硅钢组织和磁性能的影响
采用双辊薄带连铸技术试制了3.98%Si-0.71%Al无取向硅钢铸带,研究了二次冷轧法对硅钢组织和磁性能的影响。结果表明:硅钢铸带显微组织为等轴晶组织,铸带再结晶较完全,常化对铸带显微组织影响较小。二次冷轧工艺和一次冷轧工艺下,最终退火后成品显微组织为等轴晶组织,二次冷轧法最终退火后的晶粒尺寸小于一次冷轧法。二次冷轧法能够提高成品磁性能. Effect of double cold rolling on magnetic properties and microstructure of 3.98%Si-0.71%Al non-oriented silicon Steel Sheets cast by twin-roll thin strip casting process were investigated.The results show that the structure of the thin strip is equiaxed crystal,the recrystallization is complete and normalizing has lesser effect on microstructure.Using both cold rolled and double cold rolled process,the microstructure is equiaxed grain after final annealing.The average grain size of annealed shee...
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 ...
压下率对6.5%Si电工钢温轧板织构的影响规律
6.5%Si电工钢是一种优异的软磁材料,织构对其磁性能影响很大。利用温轧工艺对6.5%Si电工钢热轧板进行不同压下率轧制,研究了温轧板织构随压下率的变化规律。实验结果显示,随着压下率的增大,{100}〈110〉、{110}〈100〉和γ纤维织构在薄板表层中的强度先增强后减弱,当压下率达到75%时,沿板厚方向形成3个组织区域:表层细晶粒区({110}〈100〉取向为主)、过渡层({111}〈110〉和{111}〈112〉变形晶粒区)和中心层(以拉长的γ纤维织构和{100}〈110〉取向晶粒为主),这种组织和织构不均性对后期织构的发展有重大影响。 6.5wt% Si electric steel has excellent soft magnetic properties,on which texture play important role.In this experiment,warm rolling technique was employed to investigate the effect of rolling reduction on texture.It was found that the density of {100}〈110〉,{110}〈100〉 and γ-fiber textures first increased and then decreased with increasing of the rolling reduction.At 75% reduction,the microstructure along the thickness of the sheet formed three zones,containing surface layer with {110}〈100〉 orien...

