钢厂
电工钢热压缩时动、静态再结晶组织及取向分析
采用热模拟方法及EBSD技术,研究Fe-3 wt%Si电工钢在不同温度下组织的动、静态再结晶及晶粒取向特征,特别是少量奥氏体对铁素体动、静态再结晶组织及取向的影响。结果表明,不同温度形变的组织主要分三类:形变长条铁素体、珠光体和等轴细小铁素体。长条形变铁素体内发生动态回复或连续式的动态再结晶,奥氏体周围的铁素体动态再结晶加速,部分以传统的不连续方式动态再结晶。铁素体、奥氏体都可发生静态再结晶。奥氏体的静态再结晶在1050℃以上明显,铁素体的静态再结晶随温度的升高逐渐进行,最显著的再结晶发生在1050℃。不同温度形变的样品,其形变晶粒取向主要以<111>和<100>为主,小等轴铁素体晶粒除与大形变铁素体取向相近外,出现了<110>取向及其它取向。 Static and dynamic recrystallization and grain orientations in a hot-compressed Fe-3 wt% Si electrical steels were studied at different temperatures using Gleeble simulator and EBSD technique,particularly focusing on the effect of small amount of austenite on ferritic microstructure and orientations.The results show that microstructure of the compressed steel,depending on deformation temperature,consisted of elongated and deformed ferrite,pearlite and fine equal-axed ferrite.The elongated ferrit...
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...
无取向硅钢中的夹杂物析出在线观察
借助高温激光共聚焦显微镜,在线观察了不同Mn含量的无取向硅钢中夹杂物的尺寸、类型、数量变化。结果表明,Mn含量(质量分数)为0.77%、0.32%时,试样中的夹杂物数量分别约为1000万个/mm3、1600万个/mm3。Mn含量较高的钢种,会优先析出球形、椭球形MnS夹杂物,其析出数量较少,尺寸相对较大,可以有效抑制AlN、CuxS夹杂物析出;Mn含量较低的钢种,会在试样再加热后冷却过程中,先析出相当数量MnS夹杂物,并作为AlN夹杂物析出核心,形成MnS+AlN复合夹杂物。这种复合夹杂物数量较多,尺寸也较大。 Based on the high temperature confocal microscope, the chage of size, type, and quantity of inclusions in non-oriented silicon steels with different Mn content were observed by in-situ SEM. Results show that the inclusion quantities are 10 million per mm3 and 16 million per mm3,while the mass fractions of Mn are 0.77% and 0.32%, respectively. In the silicon steel with higher Mn content, the spherical and ellipsoidal MnS inclusion will precipitate first, which can retard the precipitation of AlN ...
冷轧无取向硅钢横向厚差控制
冷轧中中低牌号的无取向硅钢多采用万能凸度轧机(Universal crown mill,UCM)生产,其板形好坏受制于UCM轧机板形调节手段的协调使用。为掌握UCM轧机的板形控制特点,建立基于二维变厚度有限元的辊系弹性变形和基于三维差分的轧件塑性变形的六辊轧机耦合模型,对UCM轧机的板形调控性能进行详尽的分析,包括工作辊和中间辊弯辊、中间辊窜辊的调控功效、辊间接触压力分布等。在此基础上,提出可用指导生产的板形控制策略,指出UCM轧机在横向厚差控制方面的不足。针对工业生产中UCM轧机轧制无取向硅钢横向厚差大的问题,在大量仿真计算的基础上,开发具有高次曲线函数的边部变凸度(Edge variable crown,EVC)的工作辊。采用该工作辊后,各种品种的无取向硅钢的横向厚差不大于10μm的百分比由24%提高到99%,横向厚差的均值小于6μm,远小于之前的13μm。 Medium-low grade non-oriented silicon steel is rolled often by universal crown mill(UCM) during cold rolling.Its shape quality is dependent on the coordinated control of several shape adjustment devices of UCM.In order to understand the shape control characteristics of UCM,coupling model of six-high rolling mill,based on two-dimensional varying thickness finite element rolls elastic deformation model and three-dimensional finite difference strip plastic deformation model,is setup for the detaile...
基于不同B-H曲线的取向硅钢叠片中损耗和磁通的分析与验证
基于TEAM(Testing Electromagnetic Analysis Methods)Problem 21基准模型和不同类型的磁化曲线Bm-Hm及Bm-Hb数据,分别在50 Hz至200 Hz的频率范围内计算了基准模型的硅钢叠片内的损耗及磁通,并考虑集肤效应和材料的电-磁各向异性的影响。数值计算结果与实验测量结果具有很好的一致性。提出的有限元建模方法和基于模拟结果的分析、结论有助于提高大型电力变压器的电磁设计的有效性。 Based on TEAM(Testing Electromagnetic Analysis Methods) Problem 21 standard model and the different B-H(such as Bm-Hm and Bm-Hb) curves,the iron loss and magnetic flux inside the grain-oriented(GO) silicon steel lamination are modeled under different frequency(from 50 Hz to 200 Hz) in this paper,And the influences of skin effect and electric-magnetic anisotropy on the numerical simulation results have been examined.The calculated and measured results with respect to the model are in good agreeme...
钙处理对无取向硅钢中非金属夹杂物的影响
采用电解法和扫描电镜研究了300 t转炉-RH精炼钙处理对无取向硅钢板(%:≤0.005C、1.2~2.2Si、0.2~0.6Mn、≤0.20P、≤0.005S、0.2~0.6Al、0~0.01Ca)中夹杂物的影响。结果表明,钢中Al含量为0.25%和0.35%时,钢中溶解氧均小于1×10-4%,钙处理后都会产生CaS夹杂物,尤其是含0.35%Al的钢水;钙处理可以有效减少钢中的夹杂物数量,尤其是0.5μm以下的微细夹杂物数量;钙处理后夹杂物的种类以AlN、CaS为主,同时还含有少量的氧化物夹杂物以及AlN-CaS复合夹杂物,尺寸主要为1.5~5.0μm。 The effect of 300 t converter-RH refining calcium treatment on inclusions in non-oriented silicon steel sheet (%:≤0.005C,1.2~2.2Si,0.2~0.6Mn,≤0.20P,≤0.005S,0.2~0.6A1,0~0.01Ca) has been studied by electrolysis and scanning electron microscope.Results show that with 0.25%and 0.35%Al content in steel,all the dissolved oxygen in liquid is less than 1×10-4%,and the CaS inclusions are produced after calcium treatment,especial for the liquid containing 0.35%Al;the amount of inclusions in ste...

