钢厂
脉冲磁场退火对取向硅钢磁性能的影响
通过对取向硅钢进行脉冲磁场退火实验,发现在相同的退火时间(6.0 min)内,低于1 T的脉冲磁场可以在一定程度上提高取向硅钢的磁感(B8),而高于1 T的脉冲磁场则会使取向硅钢的磁性能急剧恶化.同时发现,脉冲直流电加热方式会使取向硅钢的磁性能恶化.研究表明,脉冲磁场退火有望成为一种调控材料微观结构的有效手段. We have carried out experiments of annealing by pulse magnetic field.The results show that a pulse magnetic field with intensity lower than 1 T can promote magnetic induction density(B8) of grain-oriented silicon steel,while the magnetic properties deteriorate sharply when intensity is higher than 1 T.It has also been found that heating by using pulse direct current can cause the magnetic properties to deteriorate,in contrast to the traditional heating using resistance furnace.Our research shows...
硅钢高温氧化铁皮的显微结构表征
利用电子探针面分析、状态分析及电子背散射衍射相分析技术研究硅钢高温氧化铁皮的显微结构。电子探针面分析可以直观的看出元素的分布状态,初步判断氧化铁皮的结构,而状态分析可以准确表征常规氧化铁皮中铁元素的状态,对于合金元素富集区域则通过电子背散射衍射相分析技术来标定。结果表明,高温氧化铁皮的结构主要有4层,即最外层为厚度约为10μm的Fe2O3相,次外层为Fe3O4相,中间层为FeO相上分布有颗粒状的Fe3O4相,最内层为FeO相和Si元素富集的Fe2SiO4相。其中Fe2SiO4层的分布特征与加热温度密切相关:1 100℃时,Fe2SiO4相呈颗粒状,弥散分布在FeO层;1 200℃时,Fe2SiO4相呈液态,侵入基体和疏松的FeO层,且沿着FeO晶界呈网状分布。 The microstructure of high temperature oxide scale on silicon steel was characterized by electron probe microanalyzer(EPMA)mapping analysis,state analysis and electron backscatter diffraction(EBSD)phase analysis.The element distribution and the initial structure of the oxide scale could be detected by EPMA mapping analysis apparently.And the state of iron in the conventional oxide scales could be determined by state analysis.Meanwhile,the alloy-rich region could be identified by EBSD phase analy...
低温取向硅钢高温退火抑制剂的演化
取向硅钢利用析出物作为抑制剂,抑制初次再结晶晶粒的长大,抑制剂是取向硅钢发生二次再结晶的基本条件之一。文中通过低温板坯加热技术制备取向硅钢,采用透射电镜(TEM)观察并研究了高温退火阶段抑制剂的演化过程。结果表明,渗氮后形成的非晶态Si3N4析出物不稳定,在700～750℃退火升温阶段转化为(Al,Si)N;(Al,Si)N颗粒在800℃发生团聚,随后长大并粗化;(Al,Si)N是低温取向硅钢主要抑制剂,随退火温度的升高,(Al,Si)N抑制力大幅下降。 Precipitates as inhibitor are used to inhibit the grain growth of primary recrystallization in grain-oriented silicon steel,and inhibitor is one of the basic conditions for occurring of secondary recrystallization.The grain-oriented silicon steel was produced by low temperature slab heating and nitriding technique.The evolution of inhibitor was observed by transmission electron microscopy.The results show that Si3N4 particles are precipitated after nitriding,and Si3N4 particles are amorphous and...
常化工艺对Si的质量分数为1.6%的无取向电工钢磁性能的影响
研究了常化温度、常化时间及常化后冷却速度对Si的质量分数为1.6%的无取向电工钢成品磁性能的影响。结果表明:在850~1 050℃范围内,随着常化温度的升高,成品铁损先减小后增大,成品磁感应强度先增大后减小;当常化温度为1 000℃时,成品平均铁损最低,平均磁感应强度最高;常化时间从3min延长到7min时,成品铁损先减小后增大,成品磁感应强度则呈单调下降趋势;随着常化冷却速度的降低,成品铁损先减小后增大,成品磁感应强度则呈单调增大趋势;对于Si的质量分数为1.6%的无取向电工钢,最佳的常化制度为:在1 000℃进行常化,时间5min,常化后空冷。对热轧板进行常化后,热轧板发生了不同程度的再结晶和晶粒长大。提高常化温度、延长常化时间、降低冷却速度,都能使常化板晶粒粗化,进而粗化成品板晶粒,改善磁性能。通过扫描电镜观察发现,成品板中析出物主要为AlN和MnS的复合析出物,以及少量的单独析出的AlN和MnS,而常化工艺主要是通过粗化析出相,减少细小析出相数量,从而减少对晶界钉扎作用来改善成品磁性能。 The effects of normalizing temperature,normalizing time and cooling rate after normalizing on magnetic properties of non-oriented electrical steel with mass fraction of Si of 1.6% were investigated.The results show that core loss of product decreases first and then increases,while magnetic induction increases first and then decreases with the increase of normalizing temperature from 850 to 1 050℃.Average core loss of product is the lowest and average magnetic induction is the highest when normal...
融入结构张量和活动轮廓的硅钢表面缺陷分割
为了解决在纹理背景下冷轧硅钢表面缺陷的分割问题,提出了基于局部信息结构张量和活动轮廓模型的硅钢表面缺陷分割方法。将图像的局部信息引入到结构张量中;在结构张量提取的特征空间中,以KL距离作为区域的概率密度相似性度量建立分割图像的活动轮廓模型;采用Split-Bregman数值解法对模型进行求解。运用提出的分割方法对硅钢表面的一些常见缺陷如纵向划伤、横向划伤、异物和孔洞等进行分割实验。实验结果表明,该方法可以准确地分割出硅钢表面缺陷区域,验证了该方法的有效性。 In order to address the segmentation problem for cold rolled silicon steel surface defect based on the texture background,a novel method based on structure tensor and active contour model is proposed.Image local information is introduced to the structure tensor.In the extracted feature space of structure tensor,KL distance is treated as a regional similarity measure of the probability density to establish active contour model for image segmentation.The numerical solution of Split-Bregman is used...
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...
二次冷轧的中间退火温度对2.3Si无取向硅钢组织和性能的影响
试验2.3Si无取向硅钢(/%:0.003C,2.30Si,0.16Mn,≤0.020P,≤0.005S,0.54Al)冷轧板由常化和未常化的2.5 mm热轧板冷轧至0.6 mm(压下率76%),经750~950℃2.5 min中间退火后再冷轧至0.5 mm(压下率16.7%),成品板经890℃+960℃2.5 min退火。研究了中间退火温度对该钢晶粒尺寸、织构和磁性能的影响。结果表明,随中间退火温度的升高,二次冷轧前晶粒和成品晶粒增大,成品中不利织构组分{111}和{112}减弱,磁性能得到改善。热轧板经过常化时的磁性能明显好于未经常化时的磁性能,但中间退火温度较高时常化对磁性能的有利作用减弱。 The test cold sheet of 2.3Si non-oriented silicon steel(/%:0.003C,2.30Si,0.16Mn,≤0.020P,≤0.005S,0.54Al) is first cold-rolled from normalized and un-normalizing 2.5 mm hot-rolled plate to 0.6 mm sheet(reduction 76%),then intermediate annealed at 750~950℃ for 2.5 min and double cold-rolled to 0.5 mm sheet(reduction16.7%),the finished sheet annealed at 890℃+960℃ for 2.5 min.Effect of the intermediate annealing temperature on grain size,texture and magnetic performance of the steel has been studied....
薄板坯连铸连轧流程试制含钒钛取向硅钢中氮化物析出相
通过热力学计算与模拟试验研究了含钒钛取向硅钢中氮化物析出相的析出规律与析出行为,并探讨了含钒钛元素的氮化物析出相作为薄板坯连铸连轧流程制备取向硅钢中辅助抑制剂的可行性.研究表明,在所冶炼的含钒钛取向硅钢的成分范围内,Ti N在钢液凝固末期便具备析出的热力学条件,而Al N与VN只可能在凝固后的α+γ或α+Fe3C两相区内析出.含钒钛取向硅钢中氮化物析出相以成分复杂的复合析出相为主,且随着钒钛加入量的增加,钢中抑制剂析出相总的分布密度由于含钒钛元素的氮化物析出相的增加而明显提高,使抑制剂抑制初次再结晶晶粒正常长大的能力得以加强,最终成品的磁感应强度值B8由1.857 T提升至1.898 T.同时,加入不高于0.007%的Ti与不高于0.005%的V不会影响中间脱碳退火工序的脱碳效果以及高温退火净化阶段硫、氮的脱除效果,其形成的含钒钛元素的纳米级氮化物析出相适合作为薄板坯连铸连轧流程制备取向硅钢的辅助抑制剂. The precipitation behavior of nitride precipitates in grain-oriented silicon steel containing vanadium and titanium elements produced by thin slab casting and rolling process was studied by thermodynamic calculation and simulation experiment. The feasibility of nitride precipitates containing V and Ti elements as auxiliary inhibitors was also investigated. It is found that Ti N is likely to precipitate at the final stage of solidification in the grain-oriented silicon steel,but VN and Al N can p...
