钢厂
电工钢边缘降控制研究
以马鞍山钢铁集团公司电工钢板形优化控制研究项目为背景,系统地研究了热轧、冷连轧和单机架轧机在电工钢生产过程中的边缘降控制问题。通过现场数据采集、工况数值模拟计算和工业化大生产试验,设计出适用、合理的电工钢板形控制的辊型优化曲线,满足了不同工序、不同机型的板形控制策略要求,解决了电工钢板形质量问题,取得了显著的经济效益。 Based on the project of electric steel strip shape optimization control,problem of edge drop control was systematically studied in production of electric steel of hot-rolling mill,cold-rolling mill and single stand mill.Roll optimization contour was designed out in point and reasonable by collection of work condition data,numerical simulation and test of industrial production.The shape control system can meet with the different working steps and difference mills,and quality problem of electric s...
电工钢中柱状晶对热轧和退火时晶粒取向及组织的影响
利用EBSD技术研究了电工钢中长轴平行于轧向的柱状晶样品在热轧和退火过程中组织和取向的演变规律,并与长轴平行于板法向的样品的已有研究结果进行对比。结果表明,无论柱状晶按何种方向排列,只要表面存在剪切力,热轧后都可形成剪切织构,同时中心形成轧制织构,主要包括旋转立方织构和{112}<1-10>。柱状晶造成的影响主要体现在板中心层,长轴平行于轧向排列的样品热轧时形成的粗大旋转立方晶粒要到脱碳退火后才能完全消除,但破坏了正常的不同取向晶粒间的取向差分布及尺寸均匀性,导致二次再结晶不完全及磁性能降低。 The evolution of microstructure and grain orientation in an electrical steel containing columnar grains with its long axis being parallel to the rolling direction of sheet was studied during hot rolling and annealing by EBSD technique.The results are compared with those of samples containing columnar grains being parallel to normal direction of sheet reported in the reference [3].It was shown that,whether the long axis of columnar grains was arranged in RD or ND,shear textures can be formed in t...
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...
修正GTN模型及其在预测硅钢冷轧边裂中的应用
考虑剪应变对微孔洞损伤演化的影响,对GTN损伤模型的损伤演化机制进行修正,建立了适用于不同应力三轴度水平的损伤模型。结合隐式应力更新算法和显式有限元计算,采用VUMAT子程序实现了修正GTN模型在有限元软件ABAQUS中的数值计算。通过模拟纯剪切和剪切-拉伸两组试样的损伤演化和断裂行为,验证了修正GTN模型在不同应力三轴度承载条件下的有效性。运用修正GTN损伤模型模拟含边部缺口的带钢在轧制过程中裂纹的萌生和扩展行为,模拟结果与实验相一致,表明该模型可有效地用于带钢缺陷在轧制过程中扩展行为的分析和预测。模拟和实验结果表明,带钢边部缺口在轧制过程中,缺口前沿和后沿均会萌生裂纹,且后沿裂纹扩展更为明显。 Considering the effect of shear strain of micro-void on damage evolution, a modified GTN model applicable to various stress triaxiality conditions is proposed by modifying the damage evolution mechanism of the GTN damage model. The modified model is implemented in commercial finite element software ABAQUS by combining the implicit stress update method with an explicit finite element solving algorithm and through the user-defined material subroutine VUMAT. The damage evolution and the failure pro...
脉冲电场对取向硅钢磁性能及织构的影响
采用硅钢自动测量装置及X射线衍射仪检测出样品在实验前后的磁性能参数和织构强度.结果表明:较低的电压、9 Hz、较长的处理时间以及退火温度为650℃有利于增高铁损降低比例;较低的电压、较高的频率以及退火温度为650℃有利于增加磁感应强度增高比例.最佳的提高磁性能的实验参数是:频率为9 Hz,电压为500 V,处理时间为6 min,退火温度为650℃.通过织构分析可以验证:取向硅钢磁感应强度的变化取决于{110}<001>晶粒取向度值,而{110}<001>取向度值可看成是一个反映总体平均偏离角大小情况的综合值. An automatic measurement system for silicon steel and an X-ray diffraction meter were used for measuring the magnetic property parameters and texture of ex-processed samples and processed samples.It is shown that under the condition of a lower voltage,9Hz,a longer processed time and an annealing temperature of 650℃,the decrease rate of iron loss can be increased;a lower voltage,a higher frequency and an annealing temperature of 650℃ are in favor of improving the increase rate of magnetic inducti...
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...
低温取向硅钢热轧析出物与织构的研究
采用低温板坯加热制备取向硅钢,通过透射电镜(TEM)观察并研究热轧板中的析出物,用ODF织构法研究热轧板距表面1/8、1/4和1/2处的织构分布。结果表明,热轧板中的析出物主要是密排六方AlN,AlN形貌呈规则长方形,AlN颗粒大小不等,分布密度低;热轧板中的织构沿板厚方向,由亚表层的{110}<001>织构向1/2中心层的α线织构变化,其中{110}<001>织构在热轧板距表面1/4层处最强。 The low temperature grain-oriented silicon steels were produced by acquired inhibitor method.The precipitates in hot rolling strip were observed and studied by transmission electron microscope,and the texture distribution in 1/8,1/4 and 1/2 layers of hot rolling strip were analyzed by ODF method.The results showed that the square shaped h-AlN is the main precipitates in hot rolling strip.The precipitates are varying in size and distribution.The texture of hot rolling strip in thick direction are...
