钢厂
凝固速率对定向凝固50W600无取向硅钢固液界面稳定性和枝晶间距的影响
采用ZMLMC超高梯度定向凝固装置,研究了5种凝固速率(10、35、80、150和450μm/s)对定向凝固50W600无取向硅钢的固液界面稳定性转变规律和一次、二次枝晶间距的影响。研究结果表明,在特定的温度梯度下,随着凝固速率的增加,定向凝固的固液界面由胞状晶转变为胞状枝晶,再转变为细小的树枝晶。随着凝固速率的增加,定向凝固组织的枝晶形貌逐渐细化,一次和二次枝晶间距逐渐减小,且与冷却速率之间都符合指数关系:λ1=151.73×(G L·R)-0.31,λ2=22.07×(G L·R)-0.44。当冷却速率达到4.275℃/s时,一次、二次枝晶间距分别为112μm、14.1μm。 Under the conditions of certain temperature gradient and different solidification rate,the directional solidification experiment of non-oriented electrical steel 50W600 was carried out.The microstructure of 50W600 steel was also analyzed in different solidification rate.The result shows that the solid/liquid interface of the steel undergoes an evolution from cellular,cellular dendrite and finally to fine dendrite morphologies.The dendrite refines gradually and the distance between dendrites decr...
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...
硅钢铸坯再加热过程中夹杂物的析出行为
研究了硅钢铸坯再加热过程中夹杂物的析出行为。采用非水溶液电解提取+扫描电镜观察方法,观察了试样的显微组织,统计了夹杂物的尺寸、种类、数量、分布。结果表明,均热温度为1 523 K时,水淬试样的夹杂物尺寸绝大部分小于0.5μm,0.5～5.0μm的夹杂物数量很少,没有发现5.0μm以上的夹杂物。此外,均热时间为10、30、60、90、120、240 min时,对应试样中0.05～0.2μm的夹杂物数量分别为4.04×104、4.73×104、3.70×104、3.33×104、3.10×104、1.56×104个/mm3。绝大部分夹杂物以MnS、AlN、CuxS类为主,并以三类夹杂物中的两类复合或三类复合居多。三类复合夹杂物总量占每组试样夹杂物总量的90%或以上。随均热时间延长,典型的夹杂物组成会发生如下变化:MnS+AlN+CuxS MnS+AlN AlN。与此同时,MnS、AlN、CuxS三者复合比例从45.2%(均热10 min)降为9.7%(均热240 min)。 The methods of electrolysis extraction from nonaqueous solution and scanning electron microscope were adopted to study the precipitation behavior of non-metallic inclusions in Si steel slabs during reheating processes.The morphologies,chemical compositions,quantity and size distribution of non-metallic inclusions in these steel samples were analyzed.Results show that,when the soaking temperature is 1 523 K,almost all of the non-metallic inclusions are smaller than 0.5 μm,few are in the range of ...
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...
本钢无取向硅钢热轧生产工艺路线的实践
冷轧无取向硅钢是高技术含量、高附加值产品,工艺复杂,生产周期长,过程控制难度大,被誉为钢铁产品中的\"工艺品\"。热轧生产工艺又是无取向硅钢生产的重中之重,直接决定了硅钢的铁损和电磁性等多项指标。 Cold rolled non-oriented silicon steel is high technology content 、high added value product. Its process is complex, its production cycle is of length, and its process control is difficult, which is known as the iron and steel products \" Arts and crafts\". Hot rolling production process is the top priority of non-oriented silicon steel, which directly determines iron loss of the silicon steel and electromagnetic property,as well as other many index.
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 ...
无取向硅钢热轧边裂的形成原因
利用加热炉模拟、动态再结晶以及热模拟等试验方法以及扫描电镜、金相显微镜等分析观察手段对无取向硅钢边裂的成因进行了探讨。结果表明,长时间加热使得板坯边部晶粒异常长大,晶界氧化并脱碳,轧制过程中边部温度过低,动态再结晶过程变弱,使得板坯边部延伸性能变差,是导致硅钢边裂的主要原因。建议通过适当降低铸坯加热温度、缩短保温时间、提高终轧温度来改善硅钢边裂缺陷。 The behaviors of high temperature oxidation,dynamic recrystallization,and hot ductility,microstructure evolution were investigated on the non-oriented electrical steel sheets to discuss the formation of edge crack.The key causes of cracking was found to be the coarse as-cast microstructure,grain boundary oxidation and decarburization in reheating furnace,as well as reduced temperature at strip edge region during hot rolling process resulting in reduced hot ductility and lack of enough dynamic re...
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...
