钢厂
高牌号无取向电工钢热轧板常化退火组织的EBSD分析
借助于EBSD对比研究了常化退火对高牌号无取向电工钢热轧组织和织构演变的影响,分析了常化退火对热轧板各厚度层织构的演变规律。结果表明,常化退火改善了热轧组织的均匀性,并弱化了热轧变形的γ纤维织构。升高常化退火温度,可增大热轧板的晶粒尺寸,提高{100}和{110}织构组分占有率,有利于提高无取向电工钢成品板的磁性能。 Effects of normalizing annealing on microstructure and texture of high-grade non-oriented electrical steel hot-rolled sheet were investigated by EBSD. Emphasis was put on the effects of normalizing annealing on texture evolution in the sheet thickness. The results show that the hot-rolled microstructure homogeneity is improved and the γ-fiber texture is weakened by normalizing annealing treatment. The grain size of hot-rolled sheet and intensity of the {100} and {110} favorable texture can be in...
RH精炼工艺对无取向硅钢MgO·Al_2O_3夹杂物演变影响及控制
基于BOF→RH→CSP生产工艺,研究了RH精炼过程钢中夹杂物类型演变及MgO·Al2O3夹杂物形成规律,同时对MgO·Al2O3夹杂物的形成条件进行了热力学计算,借助CFD数值模拟软件研究了RH精炼过程卷渣行为。研究发现,RH精炼过程20和30 min时,w([MgO])/w([Al2O3])为0.005~0.020,未发现MgO·Al2O3夹杂物;RH出站后夹杂物w([MgO])/w([Al2O3])为0.3~0.5,且RH精炼结束后MgO·Al2O3夹杂物占夹杂物总量的58.4%;另外,RH精炼过程钢液表面速度CFD模拟结果为0.57 m/s,大于临界卷渣速度0.45 m/s,且顶渣成分与夹杂物成分相近,存在卷渣现象。热力学计算表明,钢液与炉渣平衡时钢中w([Al])为0.31%~0.37%,w([Mg])为0.00024%~0.00028%,在MgO·Al2O3生成区域之内。减少RH处理过程卷渣,浇铸过程下渣及控制顶渣和包衬相中MgO质量分数可抑制MgO·Al2O3夹杂物形成。 Based on the practical production of non-oriented silicon steel, the evolution of inclusion type and the formation of MgO·Al2O3inclusion were analyzed in the process of BOF→RH→CSP. The thermodynamic conditions for forming MgO·Al2O3inclusion were discussed and the behavior of slag entrapment of molten steel was also simulated by CFD software during RH refining. The results showed that the value of w([MgO])/w([Al2O3]) was in the range of 0.005-0.020 and no MgO · Al2O3 inclusion was observed at 20 ...
压下率对6.5%Si电工钢温轧板织构的影响规律
6.5%Si电工钢是一种优异的软磁材料,织构对其磁性能影响很大。利用温轧工艺对6.5%Si电工钢热轧板进行不同压下率轧制,研究了温轧板织构随压下率的变化规律。实验结果显示,随着压下率的增大,{100}〈110〉、{110}〈100〉和γ纤维织构在薄板表层中的强度先增强后减弱,当压下率达到75%时,沿板厚方向形成3个组织区域:表层细晶粒区({110}〈100〉取向为主)、过渡层({111}〈110〉和{111}〈112〉变形晶粒区)和中心层(以拉长的γ纤维织构和{100}〈110〉取向晶粒为主),这种组织和织构不均性对后期织构的发展有重大影响。 6.5wt% Si electric steel has excellent soft magnetic properties,on which texture play important role.In this experiment,warm rolling technique was employed to investigate the effect of rolling reduction on texture.It was found that the density of {100}〈110〉,{110}〈100〉 and γ-fiber textures first increased and then decreased with increasing of the rolling reduction.At 75% reduction,the microstructure along the thickness of the sheet formed three zones,containing surface layer with {110}〈100〉 orien...
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...
基于CSP工艺取向硅钢初次再结晶晶界特征对宏观织构的影响
利用背散射衍射技术(EBSD)和XRD,研究了两段式脱碳退火工艺对取向硅钢纵截面初次再结晶的微区取向、取向差分布、特殊晶界(CSL)及高温退火试样高斯织构。分析了初次再结晶晶界特征对取向硅钢高温退火后宏观织构的影响。结果表明:初次再结晶的纵截面基体中Σ3和Σ5晶界使得高斯晶粒有着较高的迁移率,在高温退火时借助20o~45°的大角度晶界的界面能吞并周围{111}<112>晶粒迅速长大,形成密度水平较高的高斯织构。 Micro area orientation of primary recrystallization,the misorientation distribution,special boundaries under different two-stage decarburization annealing and the Goss texture under high temperature annealing the longitudinal section of grain-oriented silicon steel were detected by electron back scattering diffraction(EBSD) and X-ray diffraction(XRD).The effect of primary recrystallization grain boundary on macrotexture after high temperature annealing was analyzed.The results show that the Σ3 a...
硅钢常化退火炉辊印缺陷预测分类预警方法研究
针对宝钢硅钢常化退火过程中产生的退火炉辊印缺陷问题,通过实际生产的大数据与产品质量问题相结合,将数据挖掘、数据分析方法应用到实际,一定程度上解决了现场实际生产中的痛点,为现场生产提供决策支撑,避免了以前通过人工识别判定存在疏漏和无法定量判断的问题,形成了一套具有鲁棒性和可操作性的钢铁生产过程数据分析方法。通过智慧决策系统平台获取实际生产和表检仪数据,基于Pearson相关系数算法进行变量挑选和特征工程,并应用随机森林算法对数据建立分类预测模型,实现了质量问题的溯源和监控,通过数据量化预测了炉辊印缺陷是否可通过轧制消除的质量问题,识别准确率达到96.43%。 In views of the normalizing annealing furnace roll marks problem occurred in the process of normalizing annealing of silicon steel in Baosteel,by combining big data from actual production with product quality problems,data mining and data analysis methods were applied to actual production to solve the pain points and provide decision support,a robust and practical data analysis method for the steel production process has been developed,which avoided the previous problems of omission and non-quan...
二次冷轧法对薄带连铸无取向高硅钢组织和磁性能的影响
采用双辊薄带连铸技术试制了3.98%Si-0.71%Al无取向硅钢铸带,研究了二次冷轧法对硅钢组织和磁性能的影响。结果表明:硅钢铸带显微组织为等轴晶组织,铸带再结晶较完全,常化对铸带显微组织影响较小。二次冷轧工艺和一次冷轧工艺下,最终退火后成品显微组织为等轴晶组织,二次冷轧法最终退火后的晶粒尺寸小于一次冷轧法。二次冷轧法能够提高成品磁性能. Effect of double cold rolling on magnetic properties and microstructure of 3.98%Si-0.71%Al non-oriented silicon Steel Sheets cast by twin-roll thin strip casting process were investigated.The results show that the structure of the thin strip is equiaxed crystal,the recrystallization is complete and normalizing has lesser effect on microstructure.Using both cold rolled and double cold rolled process,the microstructure is equiaxed grain after final annealing.The average grain size of annealed shee...
EBSD技术在硅钢织构研究中的应用
运用电子背散射衍射(EBSD)和X射线衍射(XRD)技术对硅钢热轧板的织构在板厚方向的分布进行了研究,并分析了两种织构测量方法的特点。EBSD技术能直观给出板厚方向的微观织构,XRD能得到钢板的宏观统计织构信息,结合两种技术的分析,能更直观更精确的研究不同织构在板厚方向的分布。 The texture distribution along the thickness of the silicon steel has been investigated by electron backscatter diffraction(EBSD) and X-ray diffraction(XRD) technique.The characteristics of two technique of texture analysis have been investigated.Combined the two techniques,the texture distribution along the thickness of the silicon steel could be realized distinctly and accurately.
常化温度对TSCR流程制备低碳低硅无取向硅钢组织和性能的影响
在实验室试制了TSCR流程的低碳低硅无取向硅钢,研究了在850~1050℃不同温度常化对冷轧量0.5mm厚钢板再经950℃×7min退火后的组织、织构和磁性能的影响。结果表明:随常化温度的升高,使热轧板晶粒尺寸增大,晶界更清晰,组织均匀性更好;由于第二相AlN和MnS析出物尺寸比较大,使冷轧退火后钢板晶粒也随常化温度升高呈单调增大趋势;γ有利织构和{111}、{112}不利织构与常化温度升高同时增强,但前者增强更多;冷轧板退火后铁损随常化温度升高呈单调下降,磁感呈单调上升趋势。 The low-carbon and low-silicon non-oriented silicon steel was prepared by thin slab casting and rolling(TSCR) in lab.The effect of normalizing at different temperatures in 850-1 050℃on microstructure, texture and magnetic properties of 0.5 mm cold-rolled sheets after annealing at 950℃for 7 min was researched. The results show that with increasing the normalizing temperature,the grain size of hot-rolled sheets increased,the grain boundaries were more clear and the rnicrostructure uniformity was b...

