钢厂
冷轧无取向硅钢的边缘降控制优化研究
某冷连轧机生产无取向硅钢板材时,其边缘降的长度合格率频繁超标。为满足用户的叠片厚度精度要求,这类产品必须以增大切边量的方式来保证交货质量,而这种方式又直接降低了金属收得率,提高了生产成本。基于此,以该产线现有设备特性为基础,详细分析其软、硬件功能模式,分别对辊形与反馈控制进行全面分析与优化改进。通过现场试验论证,充分明确依托辊形优化与反馈控制程序的改进能显著提高边缘降的控制水平,该技术的使用为生产现场的边缘降控制提供了合理的技术支撑。 A cold rolling mill production of non-oriented silicon steel sheet,the thickness difference of the edge( edge-drop) is usually exceed the preset standard value,In order to meet the accuracy requirements of the user flatness,these production must be trimed wider length to meet the delivery quality of the user need, which directly reduce the metal yield and increase the manufacturing cost. Therefor,the software and hardware of the production line has been analyzed, and the work roll shape and feed...
微合金元素对冷轧取向电工钢再结晶行为的影响
以取向电工钢成分为基础,制备了含C或Mn和S的4种实验钢。观察了接近平衡析出状态实验钢经60%冷轧后在600~1000℃范围再结晶退火过程中微观组织演变,统计分析了再结晶体积分数随退火时间的变化规律,进而计算了各实验钢静态再结晶的激活能。观察了高含C实验钢退火初期再结晶晶粒优先出现的部位。结果表明900~1000℃范围内各实验钢铁素体的化学成分相似,因而其再结晶激活能基本一致。在600~800℃范围内铁素体内会有阻碍再结晶进程的三次渗碳体析出,从而使再结晶激活能明显提高。高C含量实验钢中还会有从奥氏体转变而来的粗大珠光体或渗碳体,轧制过程中其附近形成的变形区会促进600~800℃加热时该区域附近率先发生再结晶形核、降低再结晶激活能。固溶的Mn、S元素可微弱提高再结晶激活能,但高Mn、S含量会改变粗渗碳体从奥氏体析出时的形态。 Four experimental steels based on grain oriented electrical steel containing C,or Mn and S were prepared.Microstructure evolution of the steels close to a state of equilibrium precipitation were observed during annealing processes at 600-1000 ℃after 60% cold rolling,the changes of recrystallization volume fraction were analyzed statistically as the annealing was prolonged,and the activation energy for static recrystallization of the steels were calculated.The locations,where the recrystallizatio...
无取向电工钢XG800WR连铸电磁搅拌试验研究
采用铸坯低倍组织检验和化学分析的方法,研究板坯连铸机二冷区电磁搅拌器电流和频率参数对无取向电工钢XG800WR板坯中心偏析和等轴晶率的影响,结果表明:铸坯等轴晶率随着搅拌器电流强度和电流频率的增大而增加。采用二冷区电磁搅拌可减小中心易偏析元素S的偏析,试验得出:减小铸坯S偏析效果最好的电磁搅拌参数为电流380~400A,频率6Hz。 The effect of electromagnetic stirring current and frequency parameter at secondary cooling area on the central segregation and equiaxed crystal ratio of XG800WR non - oriented electrical steels slab was investigated through the methods of chemical and macrostructure analysis.The results shows that the rate of equiaxed crystal zone is going up with increasing of current intensity and current frequency.Electromagnetic stirring in the secondary cooling area can be easily reduced segregation caused...
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...
电感耦合等离子体质谱法测定硅钢中痕量铜和镍
研究了应用电感耦合等离子体质谱法(ICP-MS)测定硅钢中痕量铜和镍的分析方法。采用硝酸分解样品,通过内标校正和基体匹配消除了基体干扰的影响,同时根据测量时存在的质谱干扰情况,选择同位素65Cu和60Ni作为测定元素和通过调节仪器参数使双电荷离子的产率最低,以减少带来的干扰。该方法用于硅钢中痕量铜和镍的测定,所得的结果与ICP-AES法测定结果完全吻合,各元素测定结果的RSD值小于5%,加标回收率为97.3%~100.3%。 A method for the determination trace copper and nickel in silicon steel by inductively coupled plasma mass spectrometry(ICP-MS) was studied.The samples were dissolved in HNO3.The effect of matrix interference was eliminated by internal standard correction and matrix matching.Meanwhile,according to the mass spectral interferences in determination,the isotopes including 65Cu and 60Ni were used as measuring elements.The yield of double-charge ions were minimized by adjusting instrumental parameters...
轧制法制备低铁损高磁感6.4%(质量分数)硅钢及其织构演变
采用轧制法制备出具有低铁损高磁感0.23mm厚6.4%(质量分数)Si高硅钢。沿轧制方向的最终磁性能为B8=1.474 T,B50=1.714 T;P10/50=0.30W/kg,P15/50=0.88W/kg。利用X射线衍射及背散射电子衍射(EBSD)技术分析了高硅钢在轧制及退火过程中的织构演变过程。结果表明,通过采用大压下率热轧,确保热轧板次表层中产生更多的高斯织构,随后进行遗传;温轧板中粗大的晶粒有利于冷轧剪切带的形成;冷轧板经脱碳退火后生成强{210}〈001〉织构及次表层较强的高斯织构是在轧向上获得高磁感的原因,归因于其在{111}〈112〉冷轧形变晶粒内的剪切带优先形核并长大;最终退火后虽出现了随机取向,但以{310}〈001〉织构为代表的η织构得以保留并且增强,进一步提高了磁感。随着退火温度的升高及保温时间的延长,高硅钢薄板晶粒尺寸不断增大,铁损明显降低。 6.4wt%Si high silicon steel sheets(0.23mm thick)with low iron loss and high magnetic induction were successfully produced by rolling process.The final magnetic properties along the rolling direction(RD) were:B8=1.474T,B50=1.714T;P10/50=0.30 W/kg,P15/50=0.88 W/kg.The texture evolution during rolling and annealing was investigated by means of X-ray diffraction and electron backscatter diffraction(EBSD).It was found that more Goss textures formed in the subsurface of hot rolled plates by using larg...
稀土在无取向电工钢中应用的研究进展
稀土元素在许多钢中发挥着独特而且不可替代的重要作用。半个世纪以来,它的作用已经在各种低合金和特殊合金钢中的研究及应用中得到充分的证明;然而,作为具有稀土资源优势的中国,在属于重要功能材料的无取向电工钢中稀土的应用却落后于国外,本文就中国稀土在无取向电工钢中的应用研究作简要的评述,希望能够进一步推进此领域的研究,并且促进中国稀土在无取向电工钢中应用技术的发展,缩短与国外差距,并提出了在此应用领域今后需深入开展的研究方向。 Rare earth elements play a unique and irreplaceable role in a lot of steels,it has given the full proof by the practice of various low alloy steels and special alloy steels since half century.However,as our country has the advantage of rare earth resources,RE application technology in non-oriented electrical steels has lagged behind abroad.The application researches of rare earth in non-oriented electrical steel in our country are briefly reviewed in this paper,which hope to promote the research...
热卷箱在取向硅钢生产中的应用
热卷箱位于热连轧带钢生产线粗轧与精轧机之间,是热连轧生产中比较理想的中间保温设备。由于取向硅钢变形温度区间较窄,在生产中易出现边裂现象,同时中间坯的边部温度难于得到保证,因此一般不采用热卷箱设备生产,限制了传统热连轧生产线产品开发的品种。通过合理优化热卷箱控制工艺参数,解决了某厂传统热连轧生产线用热卷箱生产取向硅钢的边部质量问题,成功地生产出取向硅钢带。 The hot coil-box is an ideal heat retaining apparatus for hot rolling,lined between roughing mill and finishing mill. But oriented silicon steel has a narrow deformation temperature range,so that the edge crack easily occurs and it is difficult to insure the temperature of the intermediate blank. Therefore,the hot coil-box is rarely used in producing oriented silicon steel,which restricts the product development of the traditional hot rolling line. The article reasonable optimized process parame...
热轧组织对无取向硅钢织构的影响
采用X射线衍射仪分析无取向硅钢冷轧织构和再结晶退火织构的演化,研究了热轧组织对无取向硅钢织构以及磁性能的影响。结果表明,具有均匀、粗大晶粒组织的热轧板,冷轧形成更多的剪切带,导致成品板形成高的高斯织构组分,并提高了{100}织构强度,降低了γ纤维织构,最终导致成品磁感应强度升高,铁损下降。 The texture evolution of non-oriented silicon steel during cold-rolling and recrystallization annealing was investigated by X-ray diffractometer.The effects of hot band microstructure on the texture and magnetic properties of non-oriented silicon steel were analyzed.The results show that more shear bands appear during cold rolling due to homogeneous coarse grain in hot band.So strong{110}<001> texture after recrystallization annealing forms.At the same time,the {100} texture components inc...
无取向硅钢铬酸镁绝缘涂层高温固化工艺
为了确保硅钢铬酸盐涂料的环保性,需要严格控制涂料的固化工艺,保证涂料固化过程中涂料中的六价铬充分转化为三价铬。对涂料及原料进行热重分析(TG)及差示扫描量热法分析(DSC)。结果表明,MgO与铬酐混合转化为MgCrO4,使六价铬稳定性增强,其中大部分Cr6+转变为Cr3+发生在620~700℃,在450~500℃高于铬酐发生大量失重,因此必须加入还原剂保证涂料中六价铬被充分还原;超过360℃后树脂会发生分解,因此实际板温不能超过360℃;加入了还原剂的整体涂料的失重温度区间主要在260~320℃,因此涂料固化时钢板的实际温度最佳区间为320~360℃。 Because of the silicon steel chromate coating’s environmental requirements,the paint curing process must be controlled strictly to ensure all Cr( Ⅵ) transforms to Cr( Ⅲ). The TG and DSC analyses of the paint are studied. The reaction of MgO and CrO3 would generate MgCrO4,enhancing the stability of Cr( Ⅵ). The most r( Ⅵ) in MgCrO4 changes to Cr( Ⅲ) at 620-700 ℃,while the CrO3 has a large weight loss at 450-500 ℃. The reductant must be added in the paint to make sure the Cr( Ⅵ) could transform suf...

