钢厂
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...
硅钢连续退火炉无氧化加热段辐射换热研究
以能量平衡和辐射换热理论为基础,通过合理假定,建立了硅钢无氧化加热炉数学模型。采用数值计算的方法,通过自编程序,完成对带钢加热过程温度场的仿真。结果显示:数学模型能够反映带钢在无氧化炉内的加热过程,其升温曲线能够与工艺曲线相吻合;现行炉温分布并非最优,数学模型能够为炉温分布的优化、炉段的设计提供理论依据。 Mathematical model of NOF Section of Continuous Annealing Furnace is established based on energy balance and radiation heat exchange. The temperature field of steel is simulated by mathematical computation. The simulating results show that the mathematical model can reflect the heating process of silicon steel in NOF section, and the heat-up curve is coincide with the processing curve. From the results,it is known that the current furnace temperature gradient is not the best, and the mathematica...
凝固速率对定向凝固50W600无取向硅钢固液界面稳定性和枝晶间距的影响
采用ZMLMC超高梯度定向凝固装置,研究了5种凝固速率(10、35、80、150和450μm/s)对定向凝固50W600无取向硅钢的固液界面稳定性转变规律和一次、二次枝晶间距的影响。研究结果表明,在特定的温度梯度下,随着凝固速率的增加,定向凝固的固液界面由胞状晶转变为胞状枝晶,再转变为细小的树枝晶。随着凝固速率的增加,定向凝固组织的枝晶形貌逐渐细化,一次和二次枝晶间距逐渐减小,且与冷却速率之间都符合指数关系:λ1=151.73×(G L·R)-0.31,λ2=22.07×(G L·R)-0.44。当冷却速率达到4.275℃/s时,一次、二次枝晶间距分别为112μm、14.1μm。 Under the conditions of certain temperature gradient and different solidification rate,the directional solidification experiment of non-oriented electrical steel 50W600 was carried out.The microstructure of 50W600 steel was also analyzed in different solidification rate.The result shows that the solid/liquid interface of the steel undergoes an evolution from cellular,cellular dendrite and finally to fine dendrite morphologies.The dendrite refines gradually and the distance between dendrites decr...
取向电工钢加工过程中第二相粒子的析出行为
利用场发射扫描电镜观察了以MnS为主要抑制剂的普通取向电工钢加工过程中第二相粒子的分布状态,统计了粒子面密度、平均尺寸以及相应的尺寸分布.结果显示,热轧加工造成了大量第二相粒子弥散、细小地析出,同时基体仍保持过饱和状态.冷轧变形会造成第二相粒子的回溶行为,而基体的过饱和状态会减弱回溶现象.中间退火与脱碳退火过程中会同时存在新粒子的形核及已析出粒子的粗化两个过程,而在最终二次再结晶升温阶段则以第二相粒子明显粗化为主. The distribution of second phase particles in conventional grain-oriented electrical steels during manufacturing processes with MnS as inhibitors was observed by field emission scanning electron microscopy,while the areal particle density,the average particle size and the corresponding size distribution were statistically determined.It is indicated that hot rolling leads to dispersive precipitation of a large amount of fine second phase particles and the matrix keeps a supersaturated state furth...
高性能取向硅钢的工业化生产研究
采用光学显微镜、X射线衍射仪等分析了宁波钢铁有限公司生产的取向硅钢不同工序下的组织及织构演变规律。结果表明:铸坯经过热轧后,沿着厚度方向组织不均匀;一次冷轧并经脱碳退火后,组织由条状纤维状变成等轴状的初次再结晶晶粒,初次再结晶平均晶粒尺寸为18.17μm,织构主要以α织构和γ织构为主;在二次冷轧后,晶粒再次被压缩,转变为纤维状,织构主要为γ织构;经过高温退火后,发生二次再结晶,晶粒异常长大,晶粒尺寸达到厘米级,织构成分为单一且锋锐的Goss织构。 The microstructure and texture evolution of oriented silicon steel produced by Ningbo Iron and Steel Co.,Ltd.were analyzed by optical microscope and X-ray diffraction.The results showed that the microstructure of the slab was inhomogenous along the thickness direction after hot rolling.After first cold rolling and decarburizing annealing,the microstructure changed from strip fibrous to equiaxed primary recrystallized grains,and the average grain size of the primary recrystallization microstructu...
无取向电工钢XG800WR连铸电磁搅拌试验研究
采用铸坯低倍组织检验和化学分析的方法,研究板坯连铸机二冷区电磁搅拌器电流和频率参数对无取向电工钢XG800WR板坯中心偏析和等轴晶率的影响,结果表明:铸坯等轴晶率随着搅拌器电流强度和电流频率的增大而增加。采用二冷区电磁搅拌可减小中心易偏析元素S的偏析,试验得出:减小铸坯S偏析效果最好的电磁搅拌参数为电流380~400A,频率6Hz。 The effect of electromagnetic stirring current and frequency parameter at secondary cooling area on the central segregation and equiaxed crystal ratio of XG800WR non - oriented electrical steels slab was investigated through the methods of chemical and macrostructure analysis.The results shows that the rate of equiaxed crystal zone is going up with increasing of current intensity and current frequency.Electromagnetic stirring in the secondary cooling area can be easily reduced segregation caused...
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...
50W600无取向硅钢钙处理的热力学分析及实验研究
通过热力学计算及实验室研究,对钙处理前后50W600无取向硅钢退火冷轧板中夹杂物的类型、数量及尺寸进行了系统分析。结果表明,50W600无取向硅钢经钙处理后(w(Ca)=0.002 6%),钙在1 600℃的钢液中主要以固态的CaO·2Al2O3、CaO·6Al2O3及溶解钙的形式存在。在钢液的凝固过程中,钢中的溶解钙和硫反应生成了CaS和CaS-MnS复合夹杂,有效抑制了MnS的弥散析出,减少了钢中微细夹杂物的数量。同时钙处理促进了钢中微细夹杂物的聚合长大,导致显微夹杂物的数量增加。 Based on thermodynamic calculation and laboratory experiment,the type,quantity and size of inclusions in annealed cold-rolled steel sheets of 50W600 non-oriented silicon steel before and after calcium treatment were systematically studied.Results showed that after calcium treatment(w(Ca) = 0.002 6%),calcium was mainly in the form of CaO·2Al2O3,CaO·6Al2O3 and dissolved calcium in steel at 1 600 ℃.Dissolved calcium could combine with sulfur to form CaS inclusions and compound CaS-MnS inclusions du...
中低牌号无取向电工钢轧制工艺研究
热轧轧制工艺对产品性能和轧制稳定性影响很大,对中低牌号无取向电工钢,当在两相区轧制时,热轧塑性明显降低,板形变坏,易出现边裂等情况。以50W1000为例,通过对其变形抗力进行研究,得出把两相区控制在F4与F5之间为最佳轧制工艺的结论。在此基础上制定了一套较为合理的热轧工艺制度。采用新的轧制工艺后,50W1000热轧精轧的稳定性明显改善,热轧产品合格率由开发初期的40%左右提高到95%以上。 The hot rolling process has great influence on product′s performance and rolling stability.For the low medium grade non-oriented electrical steel,when non-oriented electrical steel is rolled in tow phase region,the hot rolling plasticity reduces obviously,the shape of strip goes bad and easily to crack at the edge.The deformation resistance of 50W1000 steel was investigated.The results show that the optimal rolling process is to control the two phase region between F4 and F5.Based on the results...

