钢厂
还原分离-原子荧光光谱法分析硅钢中痕量汞的不确定度评定
用还原分离-原子荧光光谱法分析了硅钢中的痕量汞.分析方法的不确定度主要来自测量重复性,样品溶液浓度,工作曲线变动性,标准溶液,移取、配制标准溶液,仪器变动性等.文章分别对上述构成合成不确定度大小的分量进行了计算讨论. Trace mercury in silicon steel and galvanized sheet was analyzed by adopting reduced separation-atomic fluorescence spectrometry.The uncertainty of the analysis method mainly comes from measurement repeatability,sample concentration,working curve volatility,standard solution,pipetting and preparation of standard solution,and instrument variability,etc.The essay conducted all calculations and discussions on the above components that determine uncertainty.
双辊连铸3%Si无取向硅钢铸带特征
针对传统工艺生产硅钢周期长、能耗大等缺点,采用双辊连铸工艺制备3%Si无取向硅钢连铸薄带,利用MEM,SEM和TEM观察了铸带的组织、织构及析出物,同时对比了Al的质量分数为0.6%和0.9%的连铸薄带在组织、织构及析出物特征方面的异同.结果表明:双辊连铸工艺生产的3%Si无取向硅钢铸带的组织为均匀等轴晶粒,平均晶粒尺寸约为300μm;织构组成随Al质量分数的不同具有明显差别,Al质量分数为0.9%的铸带中{100}织构强度是随机织构的7倍;铸带中的析出物为AlN和MnS,最大尺寸分别为500和50 nm左右. Given the lengthy production cycle,high energy consumption,and other shortcomings of the traditional process for producing silicon steel,a twin-roll casting process was used to produce 3%Si non-oriented silicon steel casting strips. MEM,SEM,and TEM were used to compare micro-structure,texture,and precipitate characteristics of a casting strip containing 0.6%Al with another containing 0.9%Al.The structure of 3%Si non-oriented silicon steel produced by the twin-roll casting process was a uniform i...
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...
电工钢冶炼过程中硫含量控制
介绍了攀钢冶炼电工钢过程硫含量变化以及过程回硫、增硫情况,采取针对性措施,如:提高铁水装入量、转炉采用石英砂代替复合造渣剂造渣、RH脱硫等,降低钢中硫含量。结果表明:采取相应措施后,电工钢炼成率大幅提高,成品w[S]≤0.008%的比例由改进前的62%提高到92.4%,取得了明显的冶金效果。 The resulfurization and the change of sulphur content in production of electrical steel is analyzed.The targeted measures have been taken,such as increase the loaded quantity of liquid iron,quartz sand replaces the composite slagging agent in the converter and RH desulfurization to decrease the sulphur content of the steel.The result shows,after the measures have been taken,the finished product ratio of electrical steel increase a lot.The ratio of sulfur content of finished product no more than ...
薄板坯连铸连轧流程试制含钒钛取向硅钢中氮化物析出相
通过热力学计算与模拟试验研究了含钒钛取向硅钢中氮化物析出相的析出规律与析出行为,并探讨了含钒钛元素的氮化物析出相作为薄板坯连铸连轧流程制备取向硅钢中辅助抑制剂的可行性.研究表明,在所冶炼的含钒钛取向硅钢的成分范围内,Ti N在钢液凝固末期便具备析出的热力学条件,而Al N与VN只可能在凝固后的α+γ或α+Fe3C两相区内析出.含钒钛取向硅钢中氮化物析出相以成分复杂的复合析出相为主,且随着钒钛加入量的增加,钢中抑制剂析出相总的分布密度由于含钒钛元素的氮化物析出相的增加而明显提高,使抑制剂抑制初次再结晶晶粒正常长大的能力得以加强,最终成品的磁感应强度值B8由1.857 T提升至1.898 T.同时,加入不高于0.007%的Ti与不高于0.005%的V不会影响中间脱碳退火工序的脱碳效果以及高温退火净化阶段硫、氮的脱除效果,其形成的含钒钛元素的纳米级氮化物析出相适合作为薄板坯连铸连轧流程制备取向硅钢的辅助抑制剂. The precipitation behavior of nitride precipitates in grain-oriented silicon steel containing vanadium and titanium elements produced by thin slab casting and rolling process was studied by thermodynamic calculation and simulation experiment. The feasibility of nitride precipitates containing V and Ti elements as auxiliary inhibitors was also investigated. It is found that Ti N is likely to precipitate at the final stage of solidification in the grain-oriented silicon steel,but VN and Al N can p...
取向硅钢生产工艺技术分析和发展趋势
介绍了普通取向硅钢(CGO)和高磁感取向硅钢(Hi-B)铸坯高温加热两次冷轧、一次冷轧和铸坯低温加热两次冷轧、一次冷轧法4种成熟生产工艺的主要技术参数,取向硅钢理论研究(Goss晶核和抑制剂)和生产技术现状。取向钢的发展趋势为:提高(110)[001]晶粒取向度,降低取向硅钢铁损,发展铸坯低温加热(≤1 300℃)和薄板坯连铸连轧流程生产取向硅钢工艺。 Main technology parameters of four developed process:cast bloom higher temperature heating-double cold rolling or single cold rolling,lower temperature heating-double cold rolling or single rolling process for production of common grain oriented silicon steel(CGO) and high magnetic induction grain oriented silicon steel(Hi-B),theory research on grain oriented steel(Goss nucleus and inhibitor) and present situation of process are summarized in this paper.The development trend of grain oriented si...
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...
微合金元素对冷轧取向电工钢再结晶行为的影响
以取向电工钢成分为基础,制备了含C或Mn和S的4种实验钢。观察了接近平衡析出状态实验钢经60%冷轧后在600～1000℃范围再结晶退火过程中微观组织演变,统计分析了再结晶体积分数随退火时间的变化规律,进而计算了各实验钢静态再结晶的激活能。观察了高含C实验钢退火初期再结晶晶粒优先出现的部位。结果表明900～1000℃范围内各实验钢铁素体的化学成分相似,因而其再结晶激活能基本一致。在600～800℃范围内铁素体内会有阻碍再结晶进程的三次渗碳体析出,从而使再结晶激活能明显提高。高C含量实验钢中还会有从奥氏体转变而来的粗大珠光体或渗碳体,轧制过程中其附近形成的变形区会促进600～800℃加热时该区域附近率先发生再结晶形核、降低再结晶激活能。固溶的Mn、S元素可微弱提高再结晶激活能,但高Mn、S含量会改变粗渗碳体从奥氏体析出时的形态。 Four experimental steels based on grain oriented electrical steel containing C,or Mn and S were prepared.Microstructure evolution of the steels close to a state of equilibrium precipitation were observed during annealing processes at 600-1000 ℃after 60% cold rolling,the changes of recrystallization volume fraction were analyzed statistically as the annealing was prolonged,and the activation energy for static recrystallization of the steels were calculated.The locations,where the recrystallizatio...
电工钢铸锭内析出相粒子特征及回溶行为
利用场发射电镜及能谱仪研究了取向电工钢薄、厚板坯铸锭中不同区域的析出相差异,确定了MnS、AlN及Fe3C的析出顺序和形貌特征。结果表明AlN以先析出的MnS为形核核心,形成粗大微米级的复合析出相。针状Fe3C既可以在复合析出相表面形成也可以在基体中单独出现,主要受冷却速度的影响。在1250℃保温1～2 h,AlN、Fe3C均可完全回溶,但部分MnS仍不回溶。MnS尺寸随着保温时间延长而增大。导致热轧板中沿轧向分布的粗大MnS,减弱了粒子钉扎力。 Precipitates in thin and thick slabs of electrical silicon steel were investigated by means of field emission SEM and EDS analysis.The precipitation sequence and the morphology of MnS,AlN and Fe3C particles were identified.AlN particles are observed to be nucleated on surface of MnS forming micron-meter-sized complex particles.Acicular Fe3C can precipitate on surface of the complex MnS/AlN particles or directly from matrix depending on cooling rate of the slabs.After holding at 1250 ℃ for 1-2 h,...
