钢厂
本钢薄板坯连铸机生产无取向电工钢的工艺优化
针对本钢薄板坯铸机在生产无取向电工硅钢的过程中存在的铸坯拉断、中包增碳、增氮等问题,进行了连铸工艺优化。通过采用新型无碳中间包覆盖剂、环保中间包干式料及专用结晶器保护渣后,降低了铸坯增碳量;通过控制钢包到中间包的增氮环节,降低钢水增氮;适当增大二冷水量,控制钢水过热度,防止铸坯拉断等生产事故的发生。改进工艺后,精炼后到成品铸坯的平均增碳量能控制在10×10-6以内,平均增氮量能控制在4×10-6以内。 The technology optimization has been adopted for preventing nitrogen increasing and carbon increasing in Benxi thin slab producing non-oriented silicon steel.Measures accordingly were adopted and satisfactory results were achieved.
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...
普通取向硅钢轧制过程中组织和织构的演变
借助电子背散射衍射(EBSD)及ZEISS-200MAT金相显微镜对某钢厂普通取向硅钢(CGO)进行研究,研究结果表明:热轧板组织、织构沿板厚方向存在明显的不均匀性,在热轧板表层及次表层发生再结晶,同时存在强度较高的Goss织构,中心层存在较强的{001}<110>变形织构。冷轧组织均呈纤维状条带组织,一次冷轧后,热轧板中的Goss织构消失,织构主要为α、γ织构,经中间脱碳退火后,α、γ织构强度减弱,并出现一定强度的Goss织构和利于Goss织构发展的{554}<225>、{332}<113>等织构,经二次冷轧后,二次冷轧织构类型与一次冷轧织构一致,但织构强度不同。 The grain-oriented silicon steel produced by a steel factory was investigated by EBSD and ZEISS-200 MAT metallographic microscope.The results show that the textures and microstructures along thickness of hot rolled slab are inhomogeneous.The surface layer and the layer near that are recrystallized structure which has a high Goss texture,but there is deformation texture{001}<110>in the central layer.The structure after cold rolling is a structure like fiber strip.After the first cold rollin...
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...
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.
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...
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...
冷轧产线硅钢激光高速切边实验研究
为了解决目前冷轧产线硅钢现有切边技术存在的微裂纹、应力、毛刺和边浪等问题,采用光纤激光器进行了高速切割实验,对激光功率、切割速度、激光模式等影响因素进行了分析,同时对高速切割时的切割前沿形状进行了研究。结果表明,切割最高速度随着功率的增加而增加;随着离焦量的增加,切割质量下降,挂渣增多,切缝宽度增加,切割深度变浅;基模激光器能量密度更高,所以薄板切割时的切割速度高于多模激光器;切割前沿随着切割速度的增加会变得平缓,速度足够大时,切割前沿甚至接近与切割方向平行,此时切缝下部存在挂渣现象。 In order to solve the problems such as micro crack,stress,burr,edge waves and so on,existing in cold rolling production line of silicon steel side cutting,experimentsof high speed laser cutting using fiber laser were carried out.Laser power,cutting speed,laser mode and other factors were analyzed,at the same time,cutting front geometries were studied.The results show that the maximum speed increases with power.And the increases of defocus result in poor quality,wider kerf and shallowerkerf.Energ...

