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薄板坯连铸连轧生产中低牌号无取向硅钢的实践
本文中简要介绍了武汉钢铁有限公司采用薄板坯连铸连轧CSP(compact strip production, CSP)工艺生产中低牌号无取向硅钢的实践情况.CSP工艺生产的硅钢具有成品磁性均匀、板形好的优势,但是在利用该技术生产中低牌号无取向硅钢时,常存在成品板表面瓦楞状缺陷严重、连铸生产效率低等问题.通过优化炼钢成分、热轧等相关工艺,可消除热轧板厚度方向中心的粗大形变组织,从源头上避免了粗大{100}<011>纤维组织的出现,消除了瓦楞状缺陷;通过提升冶炼效率和控制钢中夹杂物总量,可优化隧道炉的加热温度与在炉时间,大幅度提升了连铸生产效率,实现了中低牌号无取向硅钢的批量稳定制造,使CSP产线成为中低牌号无取向硅钢热轧板原料的主要供给生产线.如何进一步提升钢水纯洁度、提高连铸生产效率、降低生产成本,以及挖掘该产线生产薄带钢的技术优点,是未来工作的重点. This paper briefly introduces the practice of producing medium and low grade non oriented silicon steel(NGO) with CSP(compact strip production, CSP)technology in Wuhan Iron and Steel Co., Ltd.. This technology has the inherent advantages of uniform magnetic properties and good shape for silicon steel finished strip. However, in the actual production process, there are serious corrugated defects on the surface of silicon steel finished strip, and production efficiency of continuous casting is low...
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...
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...
正火对双辊薄带连铸5.28%Si-1.11%Al无取向高硅钢磁性能的影响
采用双辊薄带连铸工艺试制了2.6 mm厚5.28%Si-1.11%Al高硅钢薄带,对比了1050℃×5 min正火及不正火铸带280℃冷轧至0.5 mm后,再经900~1100℃退火的磁性能。结果表明,高硅钢铸带显微组织为等轴晶组织,正火后铸带边部晶粒长大,中心层晶粒变化较小。成品中析出物主要为较粗大的AlN和AlN+MnS复合析出物,尺寸为0.5~2.5μm。与不正火试样相比,正火试样成品铁损大幅降低,磁感小幅下降;随退火温度的升高,两种工艺下铁损和磁感都是先降低后升高,在1050℃出现最低值。 2.6 mm thickness 5.28% Si-1.11% Al non-oriented high silicon steel was produced by twin roll thin strip casting.Magnetic property of the strip un-normalized and normalized at 1050 ℃×5 min was contrasted after cold rolled to 0.5 mm at 280 ℃ and 900-1100 ℃ final annealing.The results show that microstructure of the strip is equiaxed crystal.The surface grain is coarsened and the center layer grain has little change of the normalized strip.The main precipitates are AlN and MnS+AlN with 0.5-2.5 μm s...
取向硅钢常化水冷温度模型及控制方法研究
取向硅钢常化工序主要采用现场实测带钢温度的方式测定冷却速率,并通过稳定冷却水温、调整冷却水量及喷梁运行数量等方式保证合理的冷却速率,给常化工艺设计和生产带来诸多不便。通过对常化工艺水冷过程带钢的传热分析求解,在建立带钢水冷温度模型的基础上,研究了不同冷却工艺参数对带钢温度及冷却速率的影响规律以及冷却工艺的交互作用结果。结果表明:模型计算结果能够较好地反映取向硅钢在常化水冷过程中的温度及冷却速率的变化,其计算误差为0.80%~4.11%;在特定取向硅钢厚度规格和常化工艺下,随着常化冷却水量及有效冷却长度的增加,带钢水冷温度及冷却速率与呈非线性变化;常化水冷工艺主要通过调控带钢与冷却水之间热交换量和交换时间实现对带钢温度的控制,实际生产中需综合考虑机组速度、冷却水量及有效冷却长度之间的交互作用,选定喷梁投入数量和冷却水量以获得稳定的冷却速率。 The cooling rate of normalization process mainly determined by measuring the grain oriented silicon steel strip temperature on site, and ensures the cooling rate by stabilizing the cooling water temperature, adjusting the cooling water volume and the operation quantity of spray beam, which brings inconvenience to the normalization process design and production. Based on the heat transfer of strip in the water cooling section of normalization process, the water cooling temperature model for the n...
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...
硅钢常化退火炉气-雾冷却技术及其特点分析
常化快冷是生产高牌号无取向硅钢和高磁感取向硅钢不可缺少的一个工艺环节,气-雾冷却则是实现常化快冷的关键方式之一。介绍了国内自主设计建设的常化酸洗机组气雾冷却系统的技术特性,并对其特点进行了系统分析,最后给出该系统在设计、运行参数的选择上若干注意事项,对气-雾冷却系统设计和使用具有一定的指导作用。 The normalizing rapid cooling is a indispensable process to high grade non-oriented silicon steel and high magnetic induction oriented silicon steel’ s production. The fog cooling is a key ways of coming true the normalizing rapid cooling. This paper introduces the technical features of the fog cooling system in normalizing pickling line which is the domestic independent design and construction. Meanwhile,the fog cooling system’s characteristic is analyzed systematacially. In the end,this paper ...
退火温度对无取向电工钢组织和磁性能的影响
主要研究了0.7%Si无取向电工钢退火试样的组织、晶粒尺寸和织构对其磁性能的影响。结果表明,随着退火温度的升高,晶粒尺寸逐渐增大,组织的均匀性得到改善;ɑ取向线上的纤维织构多集中于{114}<110>和{223}<110>附近,再结晶结束后,织构含量变化不大。{111}<110>织构取向密度值随温度升高而下降,{112}<111>织构与{111}<110>织构变化相反。晶粒尺寸增大对磁感强度的影响较小,而对铁损的影响较大。 Influences of microstructure,grain size and texture on the magnetic properties of 0.7% Si non-oriented electrical steels annealed samples were studied.The results show that with annealing temperature increasing the average grain size is increased gradually.Uniformity of the microstructure is improved;the textures of ɑ-fiber gathered in the vicinity of the { 114} < 110 > and { 223 } < 110 > texture.After recrystallization,the volume fraction of texture changes small.{ 111} < 110 &g...
在动态热处理条件下对取向电工钢二次再结晶的研究
对应用动态加热进行短时温度退火的取向电工钢进行了二次再结晶研究。所进行研究的实验用取向电工钢是经过终冷轧和后续罩式退火后的一条工业化生产线生产的。研究结果表明,运用短时热处理条件可引起研究钢完全的异常晶粒长大。在实验室处理的材料的织构和金相组织与工业化生产的经过终退火而获得的相同的取向电工钢类似。但是,在实验室处理的取向电工钢的二次再结晶的矩阵中可观测到\"寄生\"晶粒。从磁性观点看,这些\"寄生\"晶粒含有不理想的{111}取向织构。 The present study was made to investigate secondary recrystallization in grain-oriented steels annealed at short time temperature exposures with application of dynamical heating.The investigated GO(Grain Oriented) steels for experiments were taken from one industrial line after final cold rolling reduction and subsequent box annealing.It was shown that application of short time heat treatment conditions could lead to complete abnormal grain growth in the investigated GO steel.The texture and mic...

