钢厂
稀土处理无取向硅钢中夹杂物的控制
结合工业化生产的高效硅钢,进行了RH精炼稀土处理试验研究。针对不同的稀土处理条件,观察了夹杂物的形貌和尺寸分布,探讨了稀土处理后钢中的夹杂物形成、变化规律。结果表明:试验条件下,最佳的稀土合金添加数量为0.6~0.9 kg/t。经过合适的稀土处理后,可以有效抑制尺寸相对较小的、不规则的AlN、MnS复合夹杂生成,促进钢中微细夹杂物的聚合、上浮,钢质纯净度得到明显提高。此时,钢中全氧含量最低,脱硫效果最佳,钢中的夹杂物主要是尺寸相对较大的、近似球形或者椭球形的稀土类夹杂。 Based on the industrial production of non-oriented silicon steel,the experiment on RE treatment during the RH refining process was studied.The morphology and the size distribution were observed for the steel specimens treated with different RE treatment conditions.Further more,the formation and change of inclusions of final steel sheets after RE treatment were discussed.The results show that the suitable RE added amount was 0.6~0.9 kg/t.After the suitable RE treatment,the formation of AlN and Mn...
210 t BOF-RH-CC炼钢过程无取向硅钢XG800WR洁净度的试验研究
两炉次无取向硅钢XG800WR(/%:0.003~0.004C、0.71~0.75Si、0.32~0.33Mn、0.004~0.007S、0.016P)的炼钢流程为铁水预处理(KR)-210 t顶底复吹转炉-钢包吹氩-RH脱碳精炼-230mm×1220 mm板坯连铸。53 t中间包钢水过热度为25~30℃,钢包到中间包采用长水口全程吹氩保护浇铸,中间包至结晶器采用浸入式水口浇铸。结果表明,在RH、中间包、结晶器过程中钢中总氧以及夹杂物数量和尺寸均明显降低;但在钢包到中间包过程T[O]、[N]和钢中夹杂物数量增加,说明长水口浇铸过程存在二次氧化。连铸坯中T[O]、[N]平均他分别为11×10-6和30×10-6,显微夹杂物数量平均为4个/mm2。铸坯中的显微夹杂物主要为3~5μm的AlN,同时存在少量的MnS、Al2O3·AlN和Al2O3·MgO·MnS。 The steelmaking flow sheet for two heats non-oriented silicon steel XG800WR(/%:0.003~0.004C. 0.71~0.75Si,0.32~0.33Mn,0.004~0.007S,0.016P) is hot metal pretreatment(KR)-210 t top and bottom combined blown converter-ladle argon blowing-RH decarburization refining-230 mm×1 220 mm slab casting.The superheating extent of liquid in 53 t tundish is 25~30℃,whole casting is shielded by blowing argon with long nozzle from ladle to tundish and the submerged nozzle is adopted in casting from tundish to mold...
双辊连铸3%Si无取向硅钢铸带特征
针对传统工艺生产硅钢周期长、能耗大等缺点,采用双辊连铸工艺制备3%Si无取向硅钢连铸薄带,利用MEM,SEM和TEM观察了铸带的组织、织构及析出物,同时对比了Al的质量分数为0.6%和0.9%的连铸薄带在组织、织构及析出物特征方面的异同.结果表明:双辊连铸工艺生产的3%Si无取向硅钢铸带的组织为均匀等轴晶粒,平均晶粒尺寸约为300μm;织构组成随Al质量分数的不同具有明显差别,Al质量分数为0.9%的铸带中{100}织构强度是随机织构的7倍;铸带中的析出物为AlN和MnS,最大尺寸分别为500和50 nm左右. Given the lengthy production cycle,high energy consumption,and other shortcomings of the traditional process for producing silicon steel,a twin-roll casting process was used to produce 3%Si non-oriented silicon steel casting strips. MEM,SEM,and TEM were used to compare micro-structure,texture,and precipitate characteristics of a casting strip containing 0.6%Al with another containing 0.9%Al.The structure of 3%Si non-oriented silicon steel produced by the twin-roll casting process was a uniform i...
电工钢冶炼过程中硫含量控制
介绍了攀钢冶炼电工钢过程硫含量变化以及过程回硫、增硫情况,采取针对性措施,如:提高铁水装入量、转炉采用石英砂代替复合造渣剂造渣、RH脱硫等,降低钢中硫含量。结果表明:采取相应措施后,电工钢炼成率大幅提高,成品w[S]≤0.008%的比例由改进前的62%提高到92.4%,取得了明显的冶金效果。 The resulfurization and the change of sulphur content in production of electrical steel is analyzed.The targeted measures have been taken,such as increase the loaded quantity of liquid iron,quartz sand replaces the composite slagging agent in the converter and RH desulfurization to decrease the sulphur content of the steel.The result shows,after the measures have been taken,the finished product ratio of electrical steel increase a lot.The ratio of sulfur content of finished product no more than ...
ZnO对硅钢绝缘涂层组织与性能的影响
通过制备磷酸二氢铝硅钢涂层,研究了氧化锌对无铬涂层耐盐雾性能、电化学性能和附着性的影响。结果表明,硅钢表面涂层含有4.0%的氧化锌时,涂层具有最高的耐腐蚀性能和电化学性能,而且其致密表面最为平整,没有裂纹出现。 The effects of ZnO on the salt spray resistance property, electrochemical performance and adhesiveness of silicon steel insulating coating were studied. The results show that the best corrosion resistance and electrochemical properties can be obtained when the coating contains 4.0% oxide zinc, and the dense surface is smooth without cracks.
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...
冷轧电工钢森吉米尔轧机研究进展
森吉米尔二十辊轧机是冷轧电工钢的主要机型,具有整体刚度大,辊径小,轧制道次压下量大,产品精度高等特点,简要介绍了近年来冷轧电工钢森吉米尔二十辊轧机领域进展,在轧机结构、厚度自动控制、板形自动控制等方面的技术及研究。 20-h Sendzmir reversible mill is the main type of cold rolled electrical steel which has the characteristic of high integral stiffness,small roller diameter,high pass reduction and high product quality.In this paper,the recent progress of frame structure,automatic gauge control,automatic flatness control of Sendzmir mill is introduced.
低温板坯加热取向硅钢形变和初次再结晶织构的演变规律
采用取向分布函数和取向线分析方法对低温板坯加热取向硅钢从热轧到初次再结晶工艺阶段的织构进行了研究。研究表明:一次冷轧后各层的织构组分与热轧板各层面的织构组分存在着继承关系,次表层存在很强的{001}<110>织构,中心层的织构和热轧板的中心层相似,存在强的{001}<110>和{112}<110>织构;中间退火后发生再结晶,各织构组分的强度有所减弱,Goss织构组分再次出现;二次冷轧后沿厚度方向上的织构不均匀性不明显,{111}<112>织构强度最高,几乎是其他织构组分的1倍,{001}<110>织构大幅降低;初次再结晶后织构沿厚度方向没有明显的不均匀性,{111}<110>为最强的织构组分,并且具有一定强度的Goss位向。 The texture from the first cold rolling to the primary recrystallization of low temperature slab reheating grain-oriented electrical steel were researched by orientation distribution function and orientation distribution intensity technique.The results show that after the first stage of cold rolling,there is a strong {001}<110> texture in the subsurface and the texture in center layer is very similar to the center layer of hot band which has strong {001}<110> and {112}<110> tex...
还原分离-原子荧光光谱法分析硅钢中痕量汞的不确定度评定
用还原分离-原子荧光光谱法分析了硅钢中的痕量汞.分析方法的不确定度主要来自测量重复性,样品溶液浓度,工作曲线变动性,标准溶液,移取、配制标准溶液,仪器变动性等.文章分别对上述构成合成不确定度大小的分量进行了计算讨论. Trace mercury in silicon steel and galvanized sheet was analyzed by adopting reduced separation-atomic fluorescence spectrometry.The uncertainty of the analysis method mainly comes from measurement repeatability,sample concentration,working curve volatility,standard solution,pipetting and preparation of standard solution,and instrument variability,etc.The essay conducted all calculations and discussions on the above components that determine uncertainty.
高性能取向硅钢的工业化生产研究
采用光学显微镜、X射线衍射仪等分析了宁波钢铁有限公司生产的取向硅钢不同工序下的组织及织构演变规律。结果表明:铸坯经过热轧后,沿着厚度方向组织不均匀;一次冷轧并经脱碳退火后,组织由条状纤维状变成等轴状的初次再结晶晶粒,初次再结晶平均晶粒尺寸为18.17μm,织构主要以α织构和γ织构为主;在二次冷轧后,晶粒再次被压缩,转变为纤维状,织构主要为γ织构;经过高温退火后,发生二次再结晶,晶粒异常长大,晶粒尺寸达到厘米级,织构成分为单一且锋锐的Goss织构。 The microstructure and texture evolution of oriented silicon steel produced by Ningbo Iron and Steel Co.,Ltd.were analyzed by optical microscope and X-ray diffraction.The results showed that the microstructure of the slab was inhomogenous along the thickness direction after hot rolling.After first cold rolling and decarburizing annealing,the microstructure changed from strip fibrous to equiaxed primary recrystallized grains,and the average grain size of the primary recrystallization microstructu...
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...

