钢厂
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 ...
电工钢检测方法及标准综述
综述了电工钢从生产到成品过程中涉及到的检测项目、检测方法及仪器,并通过对电工钢标准的发展改进,详细阐述了我国现有的电工钢技术标准体系,同时对代表企业的电工钢重点指标进行了摘录对比,为综合应用电工钢检测方法并促进电工钢的发展提供了一定的参考。 This article summarizes the testing items,methods,and instruments involved in the process from manufacturing to finished products of electric steel. The current electric steel technical standards system in our country is also elaborated in detail,along with the development and improvement of electric steel standards. Meanwhile,by comparison of electric steel KPI in representitive companies,this article provides references for comprehensive application of electric steels testing methods and promo...
钇元素对6.5%Si无取向硅钢组织、高温拉伸及断裂机制的影响
通过微观组织表征、高温拉伸和断口形貌分析,研究了钇(Y)元素对6.5%Si无取向硅钢组织、高温拉伸及断裂机制的影响。研究结果表明,添加Y元素可以在钢液中形成YS和YP的复合析出。YS和YP可以充当异质形核基底,提高形核率,细化凝固组织。热轧组织不均匀,由表层至芯部分别形成等轴晶、等轴晶/拉长晶和拉长晶的混合组织。退火后,热轧变形组织转变为等轴晶,含Y实验钢的退火组织得到明显细化。500℃时效处理后,含Y实验钢具备较低的有序度,300℃的拉伸断口呈现韧性断裂特征,断后伸长率达到20.2%。相反,无Y实验钢发生脆性断裂,断后伸长率仅为2.1%。研究结果证实,Y元素可以通过组织细化和降低有序度提高6.5%Si无取向硅钢的中温塑性。 The effects of yttrium(Y)on microstructure,elevated-temperature tensile properties and fracture mechanism of 6.5% Si non-oriented electrical steel were investigated by means of microstructure characterization,high-temperature tensile test and fracture analysis.The results showed that the doping of Y introduced composite Y-rich precipitates(YS/YP)in the melt.YS and YP precipitates were qualified for heterogeneous nucleation agents,which thus raised the nucleation rate and refined the solidificati...
硅钢50A1300的流变应力和临界动态再结晶行为
用Gleeble1500D模拟试验机在变形温度为950~1 200℃、应变速率为0.01~8s-1、最大变形程度为60%的条件下,对硅钢50A1300做单道次压缩试验,首先分析了不同参数对流变应力的影响,然后用回归法确定了应力模型中的变形激活能及材料常数,得到硅钢50A1300在峰值应力条件和稳态应力条件下的变形激活能分别为270.360和91.557kJ/mol,同时得到了流变峰值应力模型,模型的相关系数为0.997。最后通过作lnθ-ε图的方法找到了硅钢50A1300发生动态再结晶的临界应变量,并回归得到峰值应变量、临界应变量与参数Z/C的关系式。 To analyze the effects of different parameters on the flow stress and critical strain of the dynamic recrystallization,single-pass compression experiments were carried out with silicon steel 50A1300 specimens using a Gleeble1500D thermal simulator at a temperature range of 950-1 200 ℃ and strain rate range of 0.01-8 s-1 under the condition of maximum deformation of 60%.The average deformation activation energy is respectively 270.360 and 91.557 kJ/mol under the peak stress and steady-state stres...
低硅钢冶炼过程硅质量分数控制
抑制回硅是低硅品种钢冶炼的重点和难点,南钢中厚板卷厂通过转炉出钢弱脱氧操作,精炼炉弱脱氧升温,脱氧、脱硫造渣,连铸严格的保护浇注及吹氩塞棒、吹氩浸入式上水口的应用等一系列工艺优化和操作的改进,使整个冶炼过程钢水回硅量稳定控制在200×10-6以内,钢水终点成分完全满足低硅钢要求。 Control of increasing silicon is the emphasis and difficulty in low silicon varieties steel smelting.The Nisco Wide Plate/Coil Plant can control the silicon content in molten steel keeping within 200×10-6 through whole steelmaking process by using oxygen residual operation in converter tapping,oxygen residual and increasing temperature,deoxidation,desulfurization,slag refining,protection cast,blowing argon by plugged nozzle,blowing argon by submerged entry nozzle in continuous casting,and other ...
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...
热处理工艺对含Mn高硅钢热轧带的组织及硬度的影响
研究了热处理工艺(退火温度、保温时间、冷却方式)对含Mn的Fe-6.5wt%Si高硅钢热轧带的显微组织及硬度的影响。结果表明,退火温度对Fe-6.5wt%Si合金的组织和显微硬度均有较大影响,随退火温度升高,平均晶粒尺寸和显微硬度均明显增大。小于1 h退火时,晶粒长大缓慢,而长时间(>1 h)退火时,一些次表层晶粒将发生异常长大。水冷组织比空冷组织略细小,但水冷显著降低了显微硬度。Mn含量提高能抑制850℃退火时晶粒的长大,并且促进退火后高硅钢的软化。 The influences of heat treatment process(annealing temperature,heating time,cooling methods) on the microstructure and microhardness of Fe-6.5wt%Si high silicon steel containing manganese for hot rolled strip were studied.The results show that the annealing temperature has a great effect on the microstructure and microhardness of Fe-6.5wt%Si alloy,and as the annealing temperature increases,the average grain sizes and microhardness will significantly increase.When annealing time for less than 1 h...
新钢1580取向硅钢宽度窄尺原因分析
取向硅钢因其高磁导率、低矫顽力和大电阻系数等特性,被广泛应用于大中型变压器和大型电动机铁芯的制造。因取向硅钢性能和成分控制严格,生产工艺复杂,故其产品代表了钢铁企业特殊钢生产的最高水平。本文介绍了新钢公司卷板厂1580热连轧线生产取向硅钢过程中出现的窄尺问题,研究了取向硅钢产品的特点,分析了热轧过程中的组织转变,并结合生产实际提出了改进措施。通过对加热炉钢坯加热模式、粗轧轧制策略、精轧轧制工艺、二级模型等方面的优化和改进,取向硅钢窄尺情况明显好转,提高了产品的成材率和市场口碑。 The oriented silicon steel is widely used in the iron core manufacture of large and mediumsized transformers and large motors because of its high permeability, low coercivity and large resistance coefficient. Due to the performance and composition control of oriented silicon steel is strict, the production process is complex,therefore, its products represent the highest level of special steel production in iron and steel enterprises. This paper introduces the problem of narrow gauge in the produ...
电脉冲对取向硅钢凝固组织的影响研究
对取向硅钢熔融态钢液进行处理,对比研究了不同脉冲参数的作用效果。结果表明,电脉冲对钢锭晶粒组织具有明显的细化作用,凝固组织等轴晶比例大幅上升。在脉冲电容、频率、处理时间和电压中,影响等轴晶比例的最显著性因素为脉冲频率;最优正交实验参数为:电容1 200μF,脉冲频率1 Hz,处理时间5 s,脉冲电压800 V;随着输入能量的增大,等轴晶率先增大后减小,脉冲输入能量为某值时,等轴晶率最大,通过经典形核理论和热力学对这一现象进行了解释。 Research on the influence of the electric pulse on the solidification structure of oriented silicon steel was preformed.Electric pulses in different parameters were applied to molten steel and results were compared.The result shows that solidification structure of oriented silicon steel can be improved by the electric pulse,and the equiaxed crystal ratio increases obviously.Among the four parameter factors of electric capacity,frequency,applied time and voltage,the most effective factor is frequ...
Cr对含Nb高强无取向硅钢组织、织构及性能的影响
高强无取向硅钢主要应用于高速电机,要求其具备高强度和优异磁性能,但目前无取向硅钢的磁性能和强度难以兼顾。因此,设计并制备了添加微量Cr的含Nb高强无取向硅钢,通过光学显微镜、EBSD、万能拉伸试验机、四探针测试仪和磁性能测量仪等研究了Cr对含Nb高强无取向硅钢微观组织、织构、力学性能及磁性能的影响。结果表明,添加质量分数为0.5%的Cr抑制了热轧组织的回复,使常化和退火组织再结晶减弱,常化和退火后有利织构面积分数增加,不利织构面积分数减小。添加质量分数为0.5%的Cr使含Nb无取向硅钢的屈服强度显著增大,磁感略升高,但对铁损几乎没有影响。Cr对屈服强度的影响一方面是由于Cr的固溶强化作用,另一方面Cr促进了Nb的析出而使Nb的析出强化效果增强;而Cr提高含Nb高强无取向硅钢的磁感主要是由于促进有利织构形成的同时抑制了不利织构的形成,使得织构因子增大;添加Cr使无取向硅钢的电阻率增加从而使铁损降低,同时Cr促进了Nb的析出,而这种富Nb析出相不仅抑制晶粒长大且会阻碍磁畴移动而使铁损增高,在两方面因素的综合作用下,添加质量分数为0.5%的Cr对含Nb高强无取向硅钢的铁损几乎没有影响。因此,... High strength non-oriented silicon steel is mainly used in high-speed motors, which requires good mechanical and magnetic properties. However, it is difficult for non-oriented silicon steel to obtain high strength and good magnetic properties at the same time. In this paper, the Cr-microalloyed Nb-containing high strength non-oriented silicon steel was designed and prepared. The effect of Cr on the microstructure, texture, mechanical properties and magnetic properties of Nb-containing high stren...
硅钢CSP工程辊底式均热炉技术特点
介绍了硅钢CSP工程辊底式均热炉的技术特性,详细阐述了辊底式均热炉工艺特点。根据硅钢均热要求,通过采取不同烧嘴布置方法和燃烧控制技术,选用耐火纤维模块和绝热材料等相关技术措施,满足了出钢温度要求。 The technical specialty for roller hearth furnace of silicon steel CSP Plant was introduced,and the technology characteristics of the roller hearth furnace were illuminated in detail.According to the reheating require of the silicon steel,different burner arrangement and combustion control methods were applied,and technology measures such as selecting refractory fiber module and insulation material and so on were taken,the temperature requirement of silicon steel was met.

