钢厂
热轧辊冷却对冷轧无取向电工钢卷纵向磁性的影响及工艺优化
通过对35W300高牌号0.35 mm冷轧无取向电工钢卷(/%:0.002C、2.71Si、0.22Mn、0.015P、0.003S、0.0020N、0.55Als)头、中、尾组织、织构及对应的磁性能的试验研究,发现因热轧时12 MPa高压水连续冷却造成接触轧辊的钢卷头、中、尾在不同温度下轧制,卷取后钢卷头部处于卷心、温度略高而冷却速度略低于钢卷尾部,致使钢卷纵向组织、织构不同,成品卷头、尾各250 m内磁感逐渐增加,铁损逐渐降低,250 m外至钢卷中部磁性能稳定。通过将热轧辊的冷却方式改为周期冷却和卷取后的层流冷却改为钢卷70 m后开始冷却,至钢卷尾部70 m前停止冷却的方式使得钢卷纵向铁损差异明显减小,磁感差异略有改善。 According to the test research on structure and texture of head,meddle and end of 35W300 high grade 0.35 mm cold rolled non-oriented electrical steel strip coil(/%:0.002C,2.71Si,0.22Mn,0.015P,0.003S,0.002 0 N,0.55Als) and corresponding magnetic properties,It is found that due to 12 MPa high pressure water continuous cooling the roller in hot rolling process led to head,middle and tail of strip rolling at different temperature and after coiling the head of strip coil being in center of coil led t...
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...
大压下率冷轧无取向硅钢再结晶织构演变
研究了冷轧95%变形量无取向硅钢不同退火温度(710~1 050℃)下再结晶织构特征.再结晶刚完成时(710℃退火),呈现强γ({111<112>~<134>)与弱{114}<481>织构特征;随退火温度升高至900℃,γ明显减弱,{114}<481>组分持续增强,形成典型的{h,1,1}<1/h,1,2>织构;进一步升温至1 050℃,再结晶织构不再发生明显变化.基于EBSD分析,{114}<481>组分的持续强化可归因于其明显的尺寸优势以及较高频率的高能晶界(取向差角为20°~45°). A non-oriented silicon steel was heavily rolled to 95% reduction and subsequently annealed at 710~1 050 ℃ to investigate recrystallization texture evolution.When annealed at 710 ℃ with complete recrystallization,the texture is characterized by a strong partial γ fiber spreading from {111}<112> to {111}<134> and a weak {114}<481> component.As annealing at 900 ℃,γ fiber is decreased significantly while {114}<481> is increased consistently,producing a typical {h,1,1}<1/h,...
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...
高强度无取向电工钢疲劳性能及断裂机制
测试了高强无取向电工钢的S-N曲线,并借助光学显微镜、扫描电子显微镜、透射电子显微镜分析了实验钢组织,疲劳断口形貌和位错结构。结果表明:室温条件下,频率为20Hz,应力比R为0.1,循环10~7周次时,实验钢的疲劳强度为360MPa,疲劳裂纹萌生于实验钢的次表面,裂纹萌生点附近有沿晶开裂现象,疲劳裂纹扩展区域有解理台阶与疲劳条纹,瞬间断裂区是韧性断裂,有大量韧窝。实验钢在循环应力作用下基体中产生了大量位错,并有驻留滑移带终止在晶界位置。 The S-N curve of a high strength non-oriented electrical steel was tested.The microstructure and fatigue fracture morphology and dislocation were analyzed by optical microscope,scanning electron microscope,transmission electron microscope.The results showed that:at room temperature and the frequency of 20 Hz and the stress ratio Rof 0.1,the fatigue strength of the experimental steel was 360 MPa when the cycle was 10~7 cycles.The fatigue crack initiation at the surface of the steel and the interg...
ICP-AES法测定硅钢中铌的不确定度评定
分析了电感耦合等离子体发射光谱法(ICP-AES)测定硅钢中铌的检测过程,讨论了该检测过程中不确定度的主要来源,建立了该方法的定量的数学模型,并根据这一模型计算出了检测结果的合成标准不确定度和扩展不确定度。 The measurement of niobium content in silicon steel by inductively coupled plasma atomic emission spectrometry(ICP-AES) was analyzed,by which the main factors affecting the uncertainty of the measurement were ascertained and the calculation formula was given.Finally,according to the formula the combined uncertainty and expanded uncertainty were obtained.
取向硅钢用特种氧化镁的应用研究
采用XRD、SEM和激光粒度仪等手段,观察并研究了不同特性氧化镁在硅钢表面形成硅酸镁底层形貌特点,并结合热力学和差热-失重分析了MgO-SiO2的反应机理。研究结果表明:粒度小,活性值高的特种氧化镁在高温退火过程中与基体表面氧化物生成的硅酸镁底层,界面中硅酸镁底层嵌入基体较多,表面致密,颗粒细小,有利于形成附着性能优良的硅酸镁底层。 Surface microstructure of Mg2SiO4 coatings formed on the surface of oriented silicon steel coated with different kinds of MgO was investigated by XRD and SEM.The reaction mechanism between MgO and SiO2 was analyzed by TG-DSC and thermodynamic calculation.Results revealed that when the MgO with finer microstructure size and higher activity is employed,a dense Mg2SiO4 layer with finer microstructure and good binding to the steel substrate can be obtained.The results are very helpful for the prepar...
大数据技术在硅钢产品质量管控中的应用实践
磁性能指标是硅钢产品最关键的质量指标之一,但是目前磁性能判定100%依赖于样品的离线实验室检测结果,生产线配置的在线检测仪的测量结果由于精度问题,不宜直接用于成品牌号判级。本文在现有硅钢产品质量管控体系基础上,利用大数据技术对生产数据进行分析与建模,构建不同磁性能指标在线检测模型,并在现有信息系统上完成模型库的集成部署,实现硅钢产品全长、多指标磁性能结果的拟合数据输出,支撑取样优化、精准分切、辅助综合判定等功能应用,进一步优化硅钢产品质量管控体系。 The magnetic performance index of silicon steel products is one of the most critical quality indexes.However,at present,100%determination of magnetic performance depends on the offline laboratory test results of samples,and the measurement results of the online detector configured in the production line cannot be applied in practice due to the accuracy problem.Based on the existing quality control system of silicon steel products,big data technology was used to analyze and model the production d...
无取向电工钢织构的演变及其沿带钢宽度方向上的差异
采用EBSD检测技术,分析了50W800无取向电工钢在重要生产工序间织构的演变以及织构沿带钢宽度方向上的差异性。结果表明:热轧板织构沿带钢宽度方向上的差异性主要体现在表层织构。带钢边部表层织构主要由旋转立方织构、α纤维织构以及少量的γ纤维织构组成,带钢宽度1/4处的表层织构主要存在高斯织构,带钢宽度1/2处的表层织构主要为(110)面织构以及少量的铜型织构。各处的带钢宽度1/4处和1/2处的织构类型基本一致,都以α纤维织构和旋转立方织构为主。冷轧后,各处的表层织构类型差异较小,均为γ纤维织构和α纤维织构。由板宽边部至中心处织构强度值逐渐降低。退火后,各处织构的组分基本一致,为较强的γ纤维织构和较弱的(100)面织构。各处织构强度值差异较小,变化趋势与冷轧板一致。 The texture of non-oriented electrical steel 50W800 was detected by EBSD technique.The evolution of the texture between important processes and the difference of texture along the width direction of strip were analyzed.The result shows that the difference along the width direction of strip of texture at the surface of hot rolled plate is most obvious.The texture at the surface of strip edge is primarily made of rotating cube texture,αfiber texture and weakγfiber texture.Goss texture is mainly co...

