钢厂
薄带连铸取向硅钢的热轧孪生行为
薄带连铸流程下取向硅钢粗大λ晶粒(〈100〉//ND,normal direction)的“遗传”会导致磁性能恶化.为解决这一问题，针对取向硅钢的热轧孪生行为开展研究，结果表明：凝固组织粗大的取向硅钢在650℃热轧时可产生大量{112}〈111〉形变孪晶，这与具有高层错能的硅钢在较高温度下难以孪生变形的传统认知不同.热轧过程中复杂的应力状态降低了变形孪晶的取向依赖性，由于具有更高的储存能，孪晶界/孪晶界及孪晶界/晶界交叉点成为再结晶形核的优先位置，大大提高了常化过程中的再结晶率，受沿孪晶界应变分布及孪晶间距离的限制，沿孪晶界形核的再结晶晶粒通常呈“饼状”,最终形成以细小且取向漫散的再结晶晶粒为主的常化组织，消除了初始凝固组织中有害的粗大λ晶粒. In strip casting grain-oriented silicon steels, the inheritance of coarse λ grains(〈100〉//ND, normal direction) can deteriorate their magnetic properties. To solve the problem, twinning behaviors in strip casting grain-oriented silicon steels during hot rolling were investigated in this work. It is found that after rolling at 650 ℃, a number of {112}〈111〉deformation twins are formed in the coarse solidification microstructure of the steels, in contrast to the well-accepted view that it is diffic...
Si在纯Fe及低硅钢中扩散行为
采用磁控溅射方法,分别在纯Fe以及低硅钢基片上沉积富Si膜,并对其进行真空扩散热处理.通过能谱分析及X射线衍射研究了Si在纯Fe与低硅钢基体中的扩散特征,运用DICTRA软件建立了扩散模型.研究发现Si在纯Fe基体中扩散时发生γ-Fe(Si)→α-Fe(Si)相转变,扩散速率受控于相界面的迁移.当沿截面Si含量梯度不足以驱动相界面正向迁移时,延长扩散时间会发生相界面回迁现象,最终趋于单一相内均匀化扩散过程.Si在低硅钢基体中的扩散符合Fick扩散第二定律. Si-rich films were deposited on pure iron and low-Si steel substrates by direct current magnetron sputtering,and then were subjected to vacuum annealing.The distribution characteristics of Si across Fe and low-Si steel substrates were studied by energy spectrum analysis(EDS) and X-ray diffraction(XRD).DICTRA software was used to simulate the diffusion models.It is found that the diffusion behavior of Si in the Fe substrate is from γ-Fe(Si) phase to α-Fe(Si) phase and the rate of diffusion is con...
锰含量对无取向电工钢组织性能的影响
研究了锰含量对w(Si)=1.8%Si无取向电工钢组织和性能的影响。结果表明,钢中锰含量从0.3%增加到1.2%时,由于α_γ相变的产生,铸坯低倍组织、热轧板金相组织及成品织构等均发生了不同程度的变化,对成品表面质量及磁性能产生了明显的影响。 The effects of manganese content on structure and properties of w(Si)=1.8% non-oriented electrical steels have been studied.Results show that with increasing manganese content to 1.2% from 0.3%,macrostructure of continuous casting slab,hot rolled band metallurgical structure and finished product texture vary in some extent because of the occurrence of α-γ phase transformation,the surface quality and magnetic properties of finished product are affected greatly.
稀土元素Ce含量对50W470无取向硅钢显微组织及性能的影响
利用光学显微镜（OM）和扫描电镜（SEM）研究了不同稀土Ce含量的50W470无取向硅钢的铸坯、热轧板和冷轧退火板的宏观和微观组织，并采用磁性能测试仪测定其磁性能。结果表明：当稀土Ce的加入量从0增加到66×10-6（质量分数）时，铸坯的柱状晶平均宽度从3.82 mm减小到3.24 mm,等轴晶率从43.1%增加到51.3%;热轧板的平均晶粒尺寸逐渐增加，从26.2μm增加到33.3μm,再结晶百分数从24%增加到37%;退火板的平均晶粒尺寸从36.2μm增加到39.3μm;磁性能测试表明，微观组织的变化有利于50W470无取向硅钢铁损降低和磁感提高。 Macro-structure and microstructure of as-cast plate, hot rolled plate and cold rolled annealed plate of 50 W470 non-oriented silicon steel with different rare earth Ce content was studied by optical microscope（OM） and scanning electron microscopy（SEM）, and their magnetic properties were measured by magnetic property tester. The results show that when the addition amount of rare earth Ce increases from 0 to 66×10-6（mass fraction）, the average width of columnar crystal of the as-cast pl...
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 ...
取向硅钢用特种氧化镁的应用研究
采用XRD、SEM和激光粒度仪等手段,观察并研究了不同特性氧化镁在硅钢表面形成硅酸镁底层形貌特点,并结合热力学和差热-失重分析了MgO-SiO2的反应机理。研究结果表明:粒度小,活性值高的特种氧化镁在高温退火过程中与基体表面氧化物生成的硅酸镁底层,界面中硅酸镁底层嵌入基体较多,表面致密,颗粒细小,有利于形成附着性能优良的硅酸镁底层。 Surface microstructure of Mg2SiO4 coatings formed on the surface of oriented silicon steel coated with different kinds of MgO was investigated by XRD and SEM.The reaction mechanism between MgO and SiO2 was analyzed by TG-DSC and thermodynamic calculation.Results revealed that when the MgO with finer microstructure size and higher activity is employed,a dense Mg2SiO4 layer with finer microstructure and good binding to the steel substrate can be obtained.The results are very helpful for the prepar...
正火对双辊薄带连铸5.28%Si-1.11%Al无取向高硅钢磁性能的影响
采用双辊薄带连铸工艺试制了2.6 mm厚5.28%Si-1.11%Al高硅钢薄带,对比了1050℃×5 min正火及不正火铸带280℃冷轧至0.5 mm后,再经900～1100℃退火的磁性能。结果表明,高硅钢铸带显微组织为等轴晶组织,正火后铸带边部晶粒长大,中心层晶粒变化较小。成品中析出物主要为较粗大的AlN和AlN+MnS复合析出物,尺寸为0.5～2.5μm。与不正火试样相比,正火试样成品铁损大幅降低,磁感小幅下降;随退火温度的升高,两种工艺下铁损和磁感都是先降低后升高,在1050℃出现最低值。 2.6 mm thickness 5.28% Si-1.11% Al non-oriented high silicon steel was produced by twin roll thin strip casting.Magnetic property of the strip un-normalized and normalized at 1050 ℃×5 min was contrasted after cold rolled to 0.5 mm at 280 ℃ and 900-1100 ℃ final annealing.The results show that microstructure of the strip is equiaxed crystal.The surface grain is coarsened and the center layer grain has little change of the normalized strip.The main precipitates are AlN and MnS+AlN with 0.5-2.5 μm s...
获得抑制剂法生产低温高磁感取向硅钢的抑制剂控制研究进展
综述了国内外大钢铁企业与研究机构采用获得抑制剂法生产低温高磁感取向硅钢的开发及应用情况,分析了以该法生产高磁感取向硅钢过程中抑制剂的控制技术,包括固有抑制剂组成方案、气态渗氮方式与工艺及高温退火工艺的制定.研究表明,固有抑制剂组成方案的设计思路大体一致,化合物抑制剂以AlN为主、硫化物为辅,同时添加少量Sn,Sb等单元素抑制剂,但组成元素含量存在一定差别;在脱碳退火后用NH3进行非平衡渗氮处理已成为气态渗氮的主要方式,但最佳方式仍未明确,具体选择需依据实际生产条件,相应脱碳及渗氮工艺的控制条件差别较大;高温退火工艺中升温制度差别不大,升温阶段退火气氛中N2含量的选择存在差别.此外,分析了抑制剂控制技术目前存在的关键问题,并指出了进一步的研究方向. The current application and exploitation on production of low-temperature high magnetic induction grain-oriented silicon steel with acquired inhibitor method at both iron and steel enterprises and research institutions in the world are reviewed. The control techniques of inhibitors, which include the composition design for inherent inhibitors, nitriding method and process, and secondary recrystallization annealing, are thoroughly analyzed and proposed. It is indicated that the design ideas for i...
低温取向硅钢热轧析出物与织构的研究
采用低温板坯加热制备取向硅钢,通过透射电镜(TEM)观察并研究热轧板中的析出物,用ODF织构法研究热轧板距表面1/8、1/4和1/2处的织构分布。结果表明,热轧板中的析出物主要是密排六方AlN,AlN形貌呈规则长方形,AlN颗粒大小不等,分布密度低;热轧板中的织构沿板厚方向,由亚表层的{110}<001>织构向1/2中心层的α线织构变化,其中{110}<001>织构在热轧板距表面1/4层处最强。 The low temperature grain-oriented silicon steels were produced by acquired inhibitor method.The precipitates in hot rolling strip were observed and studied by transmission electron microscope,and the texture distribution in 1/8,1/4 and 1/2 layers of hot rolling strip were analyzed by ODF method.The results showed that the square shaped h-AlN is the main precipitates in hot rolling strip.The precipitates are varying in size and distribution.The texture of hot rolling strip in thick direction are...
