钢厂
高效电机用冷轧无取向电工钢退火板析出物的析出特征研究
通过热力学计算,分析了实验钢中主要析出物析出的可能性。结果表明:在液相和固液两相区中,AlN和MnS均不能析出;在奥氏体区,AlN和MnS具备热力学析出条件,平衡析出温度分别为1547、1582 K。成品退火板中的析出物主要为AlN和MnS。扫描电镜下观察到的AlN形貌多为长条状,MnS形貌多为棒状或近似球形。这两种析出物占了析出物总量的85%以上,尺寸集中分布在400~800nm;复合析出物主要是(Al2O3+MnS)和(AlN+MnS),形貌不规则,尺寸集中在0.7~1.5μm;透射电镜下观察到了少量100nm以下独立的AlN析出。 According to thermodynamic calculation, the precipitation probability of precipitates was analyzed, AlN and MnS can not precipitate in liquid phase area and solid-liquid two-phase area. In austenite area, both the AlN and MnS have precipitation condition in thermodynamics and precipitates at 1547 K and 1582 K, respectively. The precipitates in annealing plate are mainly AlN and MnS. The shape of AlN is mostly strip, and MnS is stick or near sphericity. They accounted for over 85% of the total qu...
奥氏体化温度对高碳含硅钢等温转变的影响
采用XRD物相分析、金相组织观察及TEM精细组织分析研究了奥氏体组织结构状态对Fe-0.88C-1.35Si-1.03Cr-0.43Mn钢中温等温相变鼻温和孕育期的影响,以及不同温度奥氏体化后240℃等温20 min试样的组织结构特征。试验发现,随着奥氏体化温度的升高,中温等温开始转变的鼻温移向更低温度并且相变孕育期缩短;不同温度奥氏体化后同为240℃等温20 min处理,虽然均形成由贝氏体铁素体亚条平行排列构成的束状贝氏体组织,但贝氏体组织的精细结构状态不同,突出的差别在于对应低温奥氏体化贝氏体亚条端部边界具有凸起结构,而对应高温奥氏体化贝氏体亚条端部边界较为平齐且呈现楔形结构。不能简单地以马氏体切变机制认识试验钢中贝氏体组织的形成。 The influence of austenitization temperature on the incubation period and the bainitic phase transformation behaviour in high-carbon silicon steel has been investigated using X-ray diffraction(XRD), optical microscopy and transmission electron microscopy(TEM). The microstructure characteristics of the isothermal transformation(240 ℃, 20 min)products were also studied. It was found that the nose temperature of bainite transformation and incubation period decreased with the increasing austenitizin...
异步轧制硅钢的表面纳米化及轧制参数的影响
对硅钢板材分别进行异步和同步轧制,研究了轧制参数包括速比、压下量和道次对板材表面显微组织的演变的作用.结果表明,异步轧制硅钢板材表面形成了晶粒尺寸为10~50 nm,取向接近随机分布的纳米晶,而同步轧制板材的表面只形成了位错胞,证明异步轧制可以诱发表面纳米化.异步轧制板材表面纳米晶的形成过程为:在剪切力的反复作用下,高密度位错形成、滑移、湮灭和重组形成亚微米尺度的亚微晶/位错胞.随着压下量和轧制道次增加,高密度位错重复以上过程使晶粒尺寸减小、取向差增大,最终形成取向接近随机分布的纳米晶组织.大压下量和多道次是异步轧制诱发板材表面纳米化的关键,而速比的增加可以加快纳米化进程. Surface nanocrystallization(SNC) can effectively enhance the surface and global properties of the metallic materials,such as microhardness,intensity,fatigue,wear and corrosion resistances,therefore provides more promising practical industrial applicability.Up to now,several SNC treatment methods were developed based either on the principles of ball impactions or friction sliding,however,difficulty still exists for the surface treatment of large-dimensional samples with high efficiency.Recently,m...
卷取工艺对新型冷轧无取向电工钢组织性能的影响
研究了卷取工艺对一种新型含铜无取向电工钢晶粒尺寸、织构演变、铁损和磁感应强度的影响。结果表明,试样织构组分主要为{111}、{112}、{100}和高斯织构,在550℃卷取、保温2～3h,{100}织构有增强趋势,磁感应强度较高,铁损较低。 The effects of coiling process on grain size,texture,core loss and magnetic induction of a new cold rolled non-oriented electrical steel with copper were investigated.The results show that there are mainly {111},{112},{100} and {110}<001> texture.Coiling at 550℃and keeping for 2～3 hours,the {100} texture is enhanced,magnetic induction is higher and core loss is lower.
熔盐电沉积过程温度对1.6Si无取向硅钢Si扩散的影响
试验了通过NaCl-KCl-NaF-SiO2熔盐在电流密度50 mA/cm2、电沉积脉冲电流正反向比9:1和750850℃60min电沉积下阴极（/mm）20×20×0.5的1.6Si无取向冷轧硅钢片断面层硅的分布,并通过计算得出Si的扩散系数。结果表明,电沉积温度由750℃提高至850℃时,试样中Si含量增加,扩散的深度由18μm提高到40μm;电沉积温度与Si在钢中的扩散系数近似符合Arrhenius指数关系。 The distribution of silicon at cross section of cathode（/mm） 20 × 20 × 0.5 sheet of 1.6Si non-oriented cold rolled silicon steel after electro-deposit treatment by NaCl-KCl-NaF-SiO2 molten salt with current intensity 50 mA/cm2,electro-deposit pulse current positive-negative ratio 9:1 at 750 850 ℃ for 60 min has been tested and the diffusion coefficient of Si is obtained by calculation.Results show that with increasing electro-deposit temperature from 750 ℃ to 85...
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...
硅钢铸坯感应加热炉参数优化设计
采用经验设计法初步确定了取向硅钢铸坯感应加热线圈设计参数,应用Ansoft仿真软件分别对36组不同线圈高度、线圈内径的感应加热炉在不同频率下的三维整体磁场和铸坯的温度场进行了数值仿真。通过对比仿真结果,确定电磁场分布最佳的一组感应加热炉设计参数为线圈高度h=1.50 m、线圈内径D1=0.575 m、电流频率f=110 Hz。在该参数下应用Ansoft仿真软件对取向硅钢铸坯感应加热炉的温度场进行了仿真,结果发现温度场分布均匀,可满足取向硅钢铸坯加热要求。 The induction heating coil design parameters for the oriented silicon steel casting blank were determined preliminary by experience design method,and 36 groups three-dimensional electromagnetic field with different height and inside diameter of coil under different frequencies of the induction heating furnace and the temperature field of the casting blank were investigated by numerical simulation using Ansoft simulation software. By comparing the simulation results of electromagnetic field distr...
国外采用板坯低温加热工艺生产Hi-B取向电工钢最新进展
根据新日铁、JFE及浦项等国外钢铁公司2008年以来在日本专利局、欧洲专利局(EP)及世界知识产权组织(WIPO)申请公开的有关生产Hi-B取向电工钢典型专利技术,概述了近年来国外大型钢铁企业采用低温板坯加热(坯加热温度<1 280℃)技术生产Hi-B取向电工钢主要技术重点,即将调节关键化学成分Al、N、Sn及Sb等与工艺改进相结合。最后介绍了国外大型钢铁企业采用低温板坯加热技术生产Hi-B取向电工钢实例。 The latest developments on technology for manufacturing Hi-B grain oriented electrical steel sheets developed by Nippon Steel Corp.,JFE Steel and POSCO were described according to the patents published by World Intellectual Property Organization,Japan Patent Office and European Patent Office over the recent years.The low temperature slab heating process(particularly slab-heating temperature<1 280 ℃) together with suitably adjusting key chemical elements such as Al,N,Sn and Sb elements was the...
低温高磁感取向硅钢高温退火过程织构及析出物的演变行为
对低温法生产的以AlN为主抑制剂的Hi-B取向硅钢高温退火过程进行了中断实验,借助EBSD及TEM技术对高温退火连续升温过程中织构与析出物的演变进行了研究。实验结果表明,800℃时ODF图出现高斯织构组分,但强度很弱,高斯晶粒偏离角在10°以上;950~1 000℃时高斯晶粒异常长大,偏离角3~6°;高温退火过程析出物主要有球形、规则立方形及不规则多面体形3种形貌,由于渗N的影响,Zener因子先增大再减小,并且析出物在高斯晶界前沿优先粗化。 The annealing process at high temperature of Hi-B silicon steel using low slab reheat temperature and with AlN as the inhibitor has been studied by interrupting test,and the evolution of texture and precipitates during continuous heating-up in the annealing process at high temperature was analyzed by EBSD and TEM. The results showed that Goss texture appears in ODF at 800 ℃,but the intensity of Goss texture was very weak and the deviation angle was more than10°. Goss grains grow abnormally durin...
