钢厂
冷轧无取向硅钢表面麻面缺陷成因分析及其控制措施
针对某厂DMS森吉米尔轧机生产无取向硅钢表面麻面缺陷的问题,根据生产实际,对其形成原因从乳化液及工作辊两方面因素进行了分析。结果表明:乳化液对麻面缺陷的产生有一定影响,但不是主要因素,主要原因是由于二十辊森吉米尔轧机工作辊辊径较小,轧制相同长度带钢轧辊运转周期较大,容易产生疲劳失效而导致。为此,提出通过调整冷轧工序成品轧制道次的压下率以减小轧制力,从而减小工作辊的磨损疲劳;通过对轧制乳化液浓度、温度的合理控制,以改善润滑效果、提高轧制速度,而进一步缓解轧辊疲劳的改进措施,使该钢厂无取向硅钢麻面缺陷发生率由原来的18%降至0.8%,带钢表面质量明显改善。 For the problem of surface pockmarks of non-oriented silicon steel strip produced by a DMS Sendzimir mill, based on the production practice, the formation causes were analyzed from two aspects of emulsion and working roll. The results show that the emulsion has a certain effect on the formation of surface pockmarks defects, but it is not the main factor. The main reason is that the working roll diameter of the 20-high Sendzimir mill is small, and the running period of the roll rolling the same l...
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...
无取向硅钢钢液增钛原因分析
对无取向硅钢炼钢全流程钢液增钛的原因进行了分析,认为铁水钛含量、转炉出钢温度、转炉下渣量、精炼渣TiO2含量、钢水罐及RH浸入管混钢种生产是影响钢液增钛的主要原因。通过采取低钛铁水冶炼,减少转炉下渣量,提高出钢温度,添加白灰改质精炼渣等措施,均能够降低钢液中的钛含量。 After analyzing the causes leading to increased content of titanium in molten nonoriented silicon steel during whole steelmaking process, it was concluded that such factors as content of titanium in hot metal, tapping temperature from converter, quantity of roughing slag entered into the ladle from converter, content of TiO2 in refining slag, molten steel ladle car,carrying out the steelmaking of different steel grades by the same ladle and same RH immersion tube were the main causes ...
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...
高硅钢温轧过程压下率及中间退火对组织、织构的影响
传统轧制法制备6.5wt.%高硅钢过程中温轧工艺具有显著不同于3 wt.%Si的电工钢的特点及组织织构特征,是开发新型基于织构优化的高硅钢的关键环节。采用EBSD技术对通过热轧、温轧、冷轧及退火工艺制备0.3mm厚的6.5wt.%Si电工钢板的组织和织构进行分析,重点研究温轧过程中的中间退火和大、小压下率组合以控制织构。结果表明,在热轧退火板是部分再结晶组织的情况下,一次性温轧或先小形变量、中间退火后再大形变量的工艺可得到更多的Goss晶粒;经过最终退火后Goss取向会发生偏转,形成部分黄铜取向,而{111}〈112〉取向的晶粒内形核生成近Goss取向的再结晶晶粒;大压下量轧制是最终组织中{111}取向晶粒较多的主要原因。 Warm rolling,a key process of developing new type high-Si electrical steel based on texture optimization,has significant different characteristics from 3wt% Si steel in conventional preparing process. 0. 3mm thickness 6. 5wt. % Si steel,obtained by a series of processes including hot and warm rolling,intermediate annealing and then cold rolling,was analyzed from microstructure and texture by EBSD,which are utilized mainly for investigating the intermediate annealing process and the combination o...
新能源车驱动电机用电工钢用量解析计算及预测方法
对新能源汽车以及驱动电机的现有市场和未来市场规模进行梳理分析,通过自建计算公式推导出我国2021年1-11月份驱动电机用电工钢的总量,进而预测未来10年中国新能源汽车驱动电机用电工钢情况,为无取向电工钢的生产和在电机中的应用提供有价值的参考。 The current market and future market size of new energy vehicles and traction motors were analyzed,and the total amount of electrical steels used in traction motors in China from January to November 2021 was derived by using self-built calculation formulas,and then the situation in the next ten years of electrical steel used in traction motors of new energy vehicles in China was predicted.It will provide a valuable reference for the production of non-grain oriented electrical steel and its appli...
冷轧无取向硅钢横向厚差控制
冷轧中中低牌号的无取向硅钢多采用万能凸度轧机(Universal crown mill,UCM)生产,其板形好坏受制于UCM轧机板形调节手段的协调使用。为掌握UCM轧机的板形控制特点,建立基于二维变厚度有限元的辊系弹性变形和基于三维差分的轧件塑性变形的六辊轧机耦合模型,对UCM轧机的板形调控性能进行详尽的分析,包括工作辊和中间辊弯辊、中间辊窜辊的调控功效、辊间接触压力分布等。在此基础上,提出可用指导生产的板形控制策略,指出UCM轧机在横向厚差控制方面的不足。针对工业生产中UCM轧机轧制无取向硅钢横向厚差大的问题,在大量仿真计算的基础上,开发具有高次曲线函数的边部变凸度(Edge variable crown,EVC)的工作辊。采用该工作辊后,各种品种的无取向硅钢的横向厚差不大于10μm的百分比由24%提高到99%,横向厚差的均值小于6μm,远小于之前的13μm。 Medium-low grade non-oriented silicon steel is rolled often by universal crown mill(UCM) during cold rolling.Its shape quality is dependent on the coordinated control of several shape adjustment devices of UCM.In order to understand the shape control characteristics of UCM,coupling model of six-high rolling mill,based on two-dimensional varying thickness finite element rolls elastic deformation model and three-dimensional finite difference strip plastic deformation model,is setup for the detaile...
电解清洗装置在电工钢生产线上的应用
介绍了电工钢生产线连退机组的表面处理工艺,特别是电解清洗系统的工作机理、设备构造、生产工艺及各种影响因素。 This paper introduces the technology of surface treatment of continuous annealing unit in electrical steel production line,in particular the working mechanism,structure of equipment,production techniques and various influence factors of the electrolytic cleaning system.
RH精炼添加钙合金去除硅钢夹杂物研究
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、1.67kg/t钢时,钢中钙含量分别为0、2×10-6、4×10-6;随着钙合金添加量增大,钢中夹杂物粒度逐渐由0~2μm向2~4、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,或同AlN、CaS夹杂复合;粒径为5~10μm区间,钢中的夹杂物基本以钙的氧、硫化物为主。与钙处理前相比,钙合金添加量为0.67、1.00、1.67kg/t钢时,粒径小于1.0μm的微细夹杂物减少幅度分别为68.06%、87.50%、94.94%。钙合金添加量为1.67kg/t钢时,可以去除钢中绝大部分的微细夹杂物。 Ca alloy was added into the liquid steel during RH refining,and the results show that Ca concentration in final Si steel sheets is insignificant,about 0,2×10-6 and 4×10-6 when the added amount of Ca is 0.67,1.00 and 1.67 kg/t steel,respectively.With the increase in the added Ca alloy amount,the inclusions in the steel gradually change from those of 0~2 μm to those of 2~4 and 4~6 μm.Under different Ca treatments,there exist MnS and CuxS inclusions whose size is below 1 μm as well as MnS and CuxS ...

