钢厂
双辊连铸无取向硅钢铸带特征及常化作用研究
双辊连铸技术是冶金及材料领域内的一项前沿技术,对于生产高品质硅钢具有独特优势.本实验研究了一种双辊铸轧w[Si]=4.5%的无取向硅钢,考察其铸态和常化处理后样品的组织、织构及析出相尺寸特征.结果表明:铸带组织以与铸带法向成5~20(°)倾角的柱状晶为主,晶内存在少量0.3~0.4μm的AlN析出相,铸带织构以λ(<001>//ND)织构为主,表层织构漫散.950℃/10 min常化处理后,析出相尺寸增大,表层λ织构增强. As an advanced technique of metallurgy and material science,twin- roll strip casting has unique advantages for producing high quality silicon steel. The present study was aimed at a 4. 5% Si non- oriented electrical steel for analyzing the structure,texture and the size of precipitates at the initial and normalized state. The results revealed that the initial structure mainly consisted of columnar grains with 5 ~ 20( °) angle to the normal of cast strip,and some AlN precipitates of 0. 3 ~ 0. 4 μ...
高牌号无取向电工钢热轧板常化退火组织的EBSD分析
借助于EBSD对比研究了常化退火对高牌号无取向电工钢热轧组织和织构演变的影响,分析了常化退火对热轧板各厚度层织构的演变规律。结果表明,常化退火改善了热轧组织的均匀性,并弱化了热轧变形的γ纤维织构。升高常化退火温度,可增大热轧板的晶粒尺寸,提高{100}和{110}织构组分占有率,有利于提高无取向电工钢成品板的磁性能。 Effects of normalizing annealing on microstructure and texture of high-grade non-oriented electrical steel hot-rolled sheet were investigated by EBSD. Emphasis was put on the effects of normalizing annealing on texture evolution in the sheet thickness. The results show that the hot-rolled microstructure homogeneity is improved and the γ-fiber texture is weakened by normalizing annealing treatment. The grain size of hot-rolled sheet and intensity of the {100} and {110} favorable texture can be in...
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...
加热温度对W470高硅钢连铸坯氧化铁皮的影响
采用SEM、EDS和XRD对不同加热温度下W470连铸坯氧化铁皮的微观形貌及相结构进行研究。结果表明,W470氧化铁皮难以除去的原因是氧化铁皮熔化,液相包裹着FeO,凝固时发生共晶反应,生成FeO/Fe2SiO4共晶混合物,并深嵌入基体。降低加热炉的加热温度,使连铸坯全程在FeO/Fe2SiO4共晶混合物熔点(1177℃)以下加热,可降低氧化铁皮与基体的结合力,能够有效解决W470除鳞困难问题。 The microstructure and phase structure of iron scale of W470 continuous casting billet at different heating temperatures were investigated by SEM,EDS,and XRD.The results show that the reason why the iron scale of W470 removes hardly is that iron scale is melted and the FeO is surrounded by the liquid phase,which forms FeO / Fe2SiO4eutectic mixture and is embedded into the matrix after solidification.Lowering the heating temperature and keeping the continuous casting billet heating under the melt...
热轧原料断面轮廓对冷轧硅钢尺寸精度的影响分析
根据现场实际的生产控制情况,指出了热轧原料断面轮廓缺陷以一定的比列遗传给了冷轧带钢,分析了不同热轧原料断面轮廓对冷轧电工钢尺寸精度的具体影响,提出了相应的规律。并阐明了严格控制热轧原料断面轮廓形貌,对保证冷轧电工钢尺寸精度具有重大意义,对于中国现行的冷轧电工钢生产具有指导意义。 Based on the actual situation of production control,it was pointed out that the section profile defects of hot-rolled raw materials were geneticed to the cold-rolled strip.The specific impact analysis for the profile of different hot-rolled raw materials to the dimensional accuracy of cold-rolled silicon steel was analyzed.As a result, the corresponding orderliness are given;And the strict control to section profile of the hot-rolled material is of great significance to ensure the dimensional ac...
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...
轧制裂纹及热处理工艺对高硅电工钢复合板磁性能的影响
对3层高硅电工钢复合板铸坯进行热轧及温轧变形加工后,采用正火、退火两种热处理方式处理,并观察轧制过程中产生的裂纹,研究不同状态下复合板的磁性能。对不同状态下的试样进行扩散退火处理,研究复合板中裂纹变化及其对磁性能的影响。结果表明:不同热处理工艺下合金内部的裂纹尺寸差异明显,裂纹尺寸对复合板的磁性能影响显著,相对于深裂纹,其他因素的影响较小;温轧变形加工后,复合板内层出现有序组织,但该有序组织在合金存在深裂纹的前提下并不能从本质上提高合金的磁性能;扩散退火工艺可以消除复合板内部的浅裂纹及微裂纹,但不能消除尺寸较大的裂纹,故而不能显著提高存在深裂纹的复合板的磁性能。 After hot rolling and warm rolling deformation processing of casting billet for three-layer high silicon electrical steel composite plate, it was normalized and annealed for heat treatment. Then, the cracks produced during the rolling process were observed, and the magnetic properties of composite plate in different states were also investigated. Furthermore, the samples in different states were subjected to diffusion annealing treatment, and the changes of crack in composite plate and their eff...
修正GTN模型及其在预测硅钢冷轧边裂中的应用
考虑剪应变对微孔洞损伤演化的影响,对GTN损伤模型的损伤演化机制进行修正,建立了适用于不同应力三轴度水平的损伤模型。结合隐式应力更新算法和显式有限元计算,采用VUMAT子程序实现了修正GTN模型在有限元软件ABAQUS中的数值计算。通过模拟纯剪切和剪切-拉伸两组试样的损伤演化和断裂行为,验证了修正GTN模型在不同应力三轴度承载条件下的有效性。运用修正GTN损伤模型模拟含边部缺口的带钢在轧制过程中裂纹的萌生和扩展行为,模拟结果与实验相一致,表明该模型可有效地用于带钢缺陷在轧制过程中扩展行为的分析和预测。模拟和实验结果表明,带钢边部缺口在轧制过程中,缺口前沿和后沿均会萌生裂纹,且后沿裂纹扩展更为明显。 Considering the effect of shear strain of micro-void on damage evolution, a modified GTN model applicable to various stress triaxiality conditions is proposed by modifying the damage evolution mechanism of the GTN damage model. The modified model is implemented in commercial finite element software ABAQUS by combining the implicit stress update method with an explicit finite element solving algorithm and through the user-defined material subroutine VUMAT. The damage evolution and the failure pro...
低温高磁感取向硅钢高温退火过程织构及析出物的演变行为
对低温法生产的以AlN为主抑制剂的Hi-B取向硅钢高温退火过程进行了中断实验,借助EBSD及TEM技术对高温退火连续升温过程中织构与析出物的演变进行了研究。实验结果表明,800℃时ODF图出现高斯织构组分,但强度很弱,高斯晶粒偏离角在10°以上;950~1 000℃时高斯晶粒异常长大,偏离角3~6°;高温退火过程析出物主要有球形、规则立方形及不规则多面体形3种形貌,由于渗N的影响,Zener因子先增大再减小,并且析出物在高斯晶界前沿优先粗化。 The annealing process at high temperature of Hi-B silicon steel using low slab reheat temperature and with AlN as the inhibitor has been studied by interrupting test,and the evolution of texture and precipitates during continuous heating-up in the annealing process at high temperature was analyzed by EBSD and TEM. The results showed that Goss texture appears in ODF at 800 ℃,but the intensity of Goss texture was very weak and the deviation angle was more than10°. Goss grains grow abnormally durin...

