钢厂
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...
制备硅钢级氧化镁前驱体的原料水化研究
以青海盐湖水氯镁石为初级原料,采用喷雾热解法制备原料氧化镁,原料氧化镁通过水化制备硅钢级氧化镁前驱体氢氧化镁。原料氧化镁水化实验中对水化剂、水化温度、水化时间、液固比、搅拌速度及陈化时间对水化率、过滤速度和纯度的影响进行系统研究。采用均匀实验设计和DPS数据处理,(依次)通过建模分析、二次多项式模型回归建立数学模型,再通过各因素方差分析和总方差分析,确定了理论最优实验条件,再用理论最优条件作重复实验进行验证,最终确定了原料氧化镁的最佳水化条件。在水化温度60℃,水化时间105 min,液固比4,陈化时间4 h,水化剂1含量4.0%,水化剂2含量3.15%,洗水量4倍,搅拌速度120 r/min时,原料氧化镁的水化率达99.50%以上,得到的硅钢级氧化镁前驱体氢氧化镁纯度高、过滤性能良好。 By spray pyrolysis method,bischofite in Qinghai salt Lake,as primary raw material,was used to prepare precursor raw material MgO for silicon-steel MgO.The precursor raw material MgO was used for preparing Mg(OH)2 which was the precursor of silicon-steel MgO,by hydration method.In the hydration experiment of precursor raw material MgO,some experiment parameters were investigated systematically.such as the hydrated agent,the temperature and time of hydration,liquid/solid ratio that affected the hy...
Si在纯Fe及低硅钢中扩散行为
采用磁控溅射方法,分别在纯Fe以及低硅钢基片上沉积富Si膜,并对其进行真空扩散热处理.通过能谱分析及X射线衍射研究了Si在纯Fe与低硅钢基体中的扩散特征,运用DICTRA软件建立了扩散模型.研究发现Si在纯Fe基体中扩散时发生γ-Fe(Si)→α-Fe(Si)相转变,扩散速率受控于相界面的迁移.当沿截面Si含量梯度不足以驱动相界面正向迁移时,延长扩散时间会发生相界面回迁现象,最终趋于单一相内均匀化扩散过程.Si在低硅钢基体中的扩散符合Fick扩散第二定律. Si-rich films were deposited on pure iron and low-Si steel substrates by direct current magnetron sputtering,and then were subjected to vacuum annealing.The distribution characteristics of Si across Fe and low-Si steel substrates were studied by energy spectrum analysis(EDS) and X-ray diffraction(XRD).DICTRA software was used to simulate the diffusion models.It is found that the diffusion behavior of Si in the Fe substrate is from γ-Fe(Si) phase to α-Fe(Si) phase and the rate of diffusion is con...
6.5%Si高硅钢铸锭凝固组织的CAFE法模拟研究
应用CAFE法对6.5%Si高硅钢铸锭凝固组织进行了模拟研究,确定出了适合高硅钢组织模拟的模型。进一步用该模型研究了过热度及冷却条件对凝固组织的影响,结果表明,随着过热度的降低,凝固组织中柱状晶比例和晶粒平均面积均减小。水冷条件下,高硅钢铸锭凝固组织几乎全是柱状晶,而且晶粒粗大。空冷条件下,等轴晶区扩大,但柱状晶仍占主要部分。缓冷条件下,等轴晶区占主要部分,晶粒平均面积和空冷条件下相当。 The solidification structure of 6. 5% Si steel ingot was simulated based on CAFE method and the model suitable for simulating the structure of high silicon steel wad ascertained. The influence of superheat and cooling condition on the solidification structure were studied. It was shown that with the superheat decreasing,the proportion of columnar crystals decrease,and the average grain size become smaller. Under water cooling condition,the solidification structure of casting was composed of almo...
基于GTN损伤模型对含边部缺陷硅钢薄板冷轧时边裂的预测
采用拉伸试验和显微组织观测的方法确定了GTN损伤模型中的9个损伤参数,运用GTN损伤模型对冷轧硅钢薄板边部缺陷的扩展及边裂的产生进行了有限元模拟,并与预置缺口的钢板轧制试验进行对比。结果表明:轧制过程中边部缺陷是造成钢板边部裂纹萌生和扩展的一个重要原因,GTN损伤模型可用来预测含边部缺陷硅钢薄板在冷轧过程中边裂的产生;预测结果与试验结果基本一致。 The crack initiation and propagation of silicon steel strip with edge defect during cold rolling process was studied by using GTN damage model in this paper.Nine damage parameters in GTN model were identified by tensile testing and microstructure observing,and then the FE simulation of edge defect evolution of silicon steel strip during rolling process was conducted on the base of GTN damage model,and then the results were compared with rolling experimental results.The results show that the edge...
钙合金处理硅钢中的夹杂物及晶粒成长变化
采用RH精炼添加钙合金方式对硅钢进行钙处理,结果表明,钙合金添加量为0.67、1.00和1.67 kg/t钢时,钢中Ca含量分别为0、2×10-6和4×10-(6质量分数);随着钙合金添加量的增加,钢中夹杂物粒度逐渐由0~2μm向2~4μm、4~6μm偏移;不同钙处理条件下,钢中均存在粒径小于1μm和粒径为1~5μm的MnS、CuxS夹杂物,后者或单独存在,或与AlN、CaS夹杂复合;钢中粒径为5~10μm的夹杂物基本以Ca的氧化物和硫化物为主。与未经钙处理的炉次相比,钙合金添加量为0.67、1.00和1.67 kg/t钢时,粒径小于1.0μm的夹杂物减少幅度分别为68.06%、87.50%和94.94%。钙合金添加量为1.67 kg/t钢时,可以去除钢中绝大部分的微细夹杂物。 In order to improve the properties of final silicon steels,the calcium treatment was adopted by adding Ca alloys into the liquid steel during the RH refining process.Results show that when the addition of Ca alloys is 0.67 kg/t,1.00 kg/t and 1.67 kg/t,the corresponding Ca content in silicon steels is 0,2 × 10-6 and 4 × 10-6 respectively.With the increase of Ca alloy addition,the particle sizes of inclusions in steels become 2~4 μm and 4~6 μm,from 0~2 μm.Under different calcium treatments,there e...
微量Sn对0.4%Si无取向硅钢组织和磁性能的影响
结合实际生产0.4%Si无取向硅钢,统计了不含Sn和0.025%Sn无取向硅钢的磁性能变化,利用金相显微镜、X射线衍射仪观察分析不同成分下试样的显微组织和微观织构。试验结果表明:Sn元素可以显著降低无取向硅钢的晶粒尺寸,0.025%Sn试样的平均晶粒尺寸比不含Sn减小28.4%;加入Sn元素后抑制了无取向硅钢中不利于磁性能的{111}面织构组分强度,提高了对磁性能有利的{100}面织构组分强度,0.025%Sn与不含Sn相比磁感均值从1.756 T提升至1.768 T,铁损均值从5.476 W/kg降低至5.204 W/kg,明显改善了无取向硅钢磁性能。 In this paper combined with the actual production of 0.4% Si non oriented silicon steel, the magnetic properties of non oriented silicon steel without Sn and 0.025% Sn were counted. The microstructure and microtexture of samples with different compositions were observed and analyzed by metallographic microscope and X-ray diffraction. The results show that: Sn can significantly reduce the grain size of non oriented silicon steel, and the average grain size of 0.025% Sn sample is 28.4% smaller tha...
稀土元素Ce含量对50W470无取向硅钢显微组织及性能的影响
利用光学显微镜(OM)和扫描电镜(SEM)研究了不同稀土Ce含量的50W470无取向硅钢的铸坯、热轧板和冷轧退火板的宏观和微观组织,并采用磁性能测试仪测定其磁性能。结果表明:当稀土Ce的加入量从0增加到66×10-6(质量分数)时,铸坯的柱状晶平均宽度从3.82 mm减小到3.24 mm,等轴晶率从43.1%增加到51.3%;热轧板的平均晶粒尺寸逐渐增加,从26.2μm增加到33.3μm,再结晶百分数从24%增加到37%;退火板的平均晶粒尺寸从36.2μm增加到39.3μm;磁性能测试表明,微观组织的变化有利于50W470无取向硅钢铁损降低和磁感提高。 Macro-structure and microstructure of as-cast plate, hot rolled plate and cold rolled annealed plate of 50 W470 non-oriented silicon steel with different rare earth Ce content was studied by optical microscope(OM) and scanning electron microscopy(SEM), and their magnetic properties were measured by magnetic property tester. The results show that when the addition amount of rare earth Ce increases from 0 to 66×10-6(mass fraction), the average width of columnar crystal of the as-cast pl...
硅钢级氧化镁反应行为的研究
利用DSC、XRD,结合热焓分析对硅钢级氧化镁和二氧化硅的固相反应行为进行了研究。比较了不同二氧化硅原料及混合方法对硅钢级氧化镁反应性的影响,找到了一种更为有效的硅钢级氧化镁反应性的评估方法,克服了传统柠檬酸活性法在比较不同厂家生产的氧化镁的反应性上的局限性。进一步研究了Na2B4O7添加剂、TiO2添加剂对氧化镁和二氧化硅反应行为的影响,结果表明,Na2B4O7添加剂含量的增加对反应有利,而TiO2添加剂对反应有阻碍作用。 The solid-state reaction behavior between silicon-steel grade MgO and SiO2 was investigated by DSC and XRD combined with enthalpimetric analysis.The influence of different kinds of SiO2 and different preparation methods were studied and a specifical measurement that is more reliable was proposed to evaluate reactivity of silicon steel grade MgO.It overcomes the limitation of the traditional citric acid activity(CAA) method,which can not be used to evaluate the reactivity of...
电脉冲对取向硅钢凝固组织的影响研究
对取向硅钢熔融态钢液进行处理,对比研究了不同脉冲参数的作用效果。结果表明,电脉冲对钢锭晶粒组织具有明显的细化作用,凝固组织等轴晶比例大幅上升。在脉冲电容、频率、处理时间和电压中,影响等轴晶比例的最显著性因素为脉冲频率;最优正交实验参数为:电容1 200μF,脉冲频率1 Hz,处理时间5 s,脉冲电压800 V;随着输入能量的增大,等轴晶率先增大后减小,脉冲输入能量为某值时,等轴晶率最大,通过经典形核理论和热力学对这一现象进行了解释。 Research on the influence of the electric pulse on the solidification structure of oriented silicon steel was preformed.Electric pulses in different parameters were applied to molten steel and results were compared.The result shows that solidification structure of oriented silicon steel can be improved by the electric pulse,and the equiaxed crystal ratio increases obviously.Among the four parameter factors of electric capacity,frequency,applied time and voltage,the most effective factor is frequ...
无抑制剂取向硅钢概述
概述了无抑制剂法生产取向电工钢的特性及其用途;总结无抑制剂生产取向电工钢的原理及工艺方案.重点讨论了成分方案,即元素对磁性能的影响和最终高温退火方案对二次再结晶的影响.研究结果表明,无抑制剂取向硅钢化学成分范围没有普通取向硅钢和高磁感取向硅钢严格,提高了成材率;最终高温退火决定了二次再结晶的好坏,从而最终决定成品磁性能,最佳的高温退火温度在850~950℃之间. This article provides an overview on the characteristics and uses of inhibitorless process producing grain-oriented electrical steels.The mechanism of inhibitorless process and technology programs were discussed.The results show that the chemical composition and final annealing were determined according to magnetic properties.The inhibitor-free grain oriented silicon steel has loose range of chemical composition;Secondary recrystallization occurs mainly in the final annealing and the best anneal...
冷轧取向硅钢工程混凝土结构裂缝控制施工技术
冷轧取向硅钢工程中有很多的超长、大体积以及薄壁的混凝土结构,裂缝控制是土建施工的关键。在工程中,按照\"抗放兼施、先放后抗、以抗为主\"的原则,采用\"无缝分块跳仓法\",防止超长混凝土结构收缩产生裂缝;在隧道和池体的底板与墙板施工中,采用\"整体浇筑\"法,避免了墙板因约束应力而产生的裂缝。 In the Cold-rolled grain-oriented silicon steel project,there are many overlength,bulk mass,thin-walled concretes structures,how to control the crack is the key of civil engineering construction.In these projects,according to the principle of\"release with resist,resist before release,resist is dominant \",the crack of the over-long structure and shrinkage can be prevented by the method of\"seamless block skip bin \".In the construction of the bottom plate and wall of the tunnel and the pool,the cra...

