钢厂
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...
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...
稀土Ce对含Sn高磁感无取向电工钢磁性能及夹杂物的影响
研究稀土Ce的添加对含Sn高磁感无取向电工钢磁性能及夹杂物的影响。对比分析了两种成分钢的磁性能以及各过程工艺条件下夹杂物种类和分布情况。结果表明,在含Sn高磁感无取向电工钢中加入稀土元素Ce可以粗化夹杂物,提高成品晶粒的均匀性,有效降低铁损;同时Ce的添加不影响Sn元素提高磁感的效果,磁感保持不变。 Effect of Ce on magnetic properties and inclusion of Sn-bearing high permeability non-oriented electrical steel was investigated. A comparative analysis of the magnetic properties and the types and distributions of inclusion in the two sheets with different composition shows that the addition of Ce to the Sn-bearing high permeability non-oriented electrical steel can coarse the inclusion,improve the homogeneity of the finished grain and effectively decrease the core loss. Also,the addition of Ce...
氧硫交互作用对硅钢中非金属夹杂物生成的影响
结合工业化生产的无取向硅钢,探讨了氧硫交互作用对钢中夹杂物生成的影响。借助非水溶液电解+扫描电镜法,研究了不同O、S含量下钢中夹杂物的变化规律。结果表明,本实验条件下,提高O含量、降低S含量,会劣化热轧组织再结晶效果。在劣化效果上,O的作用大于S;低Si、无Al硅钢中,应尽可能降低O含量、适当提高S含量,以粗化钢中微细夹杂物,减少尺寸小于1.0μm的夹杂物的数量;O、S含量与钢中夹杂物数量不具有关联性。生产过程中,不仅要严格控制O、S含量,还要严格控制生产工艺,以免生成较多的有害夹杂物。 Based on the industrial production of non-oriented silicon steel,the effects of interaction between oxygen and sulfur on the formation of inclusions were discussed.The change of non-metallic inclusions in steel sheets was investigated by means of electrolysis with non-aqueous solution under different oxygen and sulfur content.Results show that the recrystallization microstructure of hot rolled sheets will be deteriorated with the increase of oxygen content and the decrease of sulfur content.The ...
二次冷轧法与三次冷轧法制备取向硅钢薄带的织构转变规律
本文以热轧常化板为初始材料,采用二次冷轧法与三次冷轧法制备了0.1 mm厚的取向硅钢薄带,测定相应的磁性能,并通过EBSD取向成像技术检测了二次冷轧法与三次冷轧法各工艺过程中织构与组织演变规律。结果表明,采用最终冷轧压下率适中的三次冷轧法,能在冷轧至0.1 mm时保存较多的高斯晶核,使得高温退火后的磁性能明显优于二次冷轧法。最终冷轧压下率通过影响脱碳退火后样品中的{111}<112>织构组分及Goss晶粒数量对最终二次再结晶产生重要影响。 Grain-oriented silicon steel sheets with a thickness of 0. 1 mm were produced from hot-rolled and normalized sheets by two-step-rolling and three-step-rolling methods. Their magnetic properties were measured,and the textures were detected by EBSD technique. The results show that the three-step-rolling method,which has a moderate reduction rate of final cold rolling,can maintain more { 110} < 001 >nucleus,and thus obtaining better magnetic properties compared with the two-step-method. The f...
奥氏体化温度对高碳含硅钢等温转变的影响
采用XRD物相分析、金相组织观察及TEM精细组织分析研究了奥氏体组织结构状态对Fe-0.88C-1.35Si-1.03Cr-0.43Mn钢中温等温相变鼻温和孕育期的影响,以及不同温度奥氏体化后240℃等温20 min试样的组织结构特征。试验发现,随着奥氏体化温度的升高,中温等温开始转变的鼻温移向更低温度并且相变孕育期缩短;不同温度奥氏体化后同为240℃等温20 min处理,虽然均形成由贝氏体铁素体亚条平行排列构成的束状贝氏体组织,但贝氏体组织的精细结构状态不同,突出的差别在于对应低温奥氏体化贝氏体亚条端部边界具有凸起结构,而对应高温奥氏体化贝氏体亚条端部边界较为平齐且呈现楔形结构。不能简单地以马氏体切变机制认识试验钢中贝氏体组织的形成。 The influence of austenitization temperature on the incubation period and the bainitic phase transformation behaviour in high-carbon silicon steel has been investigated using X-ray diffraction(XRD), optical microscopy and transmission electron microscopy(TEM). The microstructure characteristics of the isothermal transformation(240 ℃, 20 min)products were also studied. It was found that the nose temperature of bainite transformation and incubation period decreased with the increasing austenitizin...
高硫硅钢的硫化物析出行为及其微观组织和电磁性能变化
为了弄清楚高硫硅钢中的硫化物析出行为及其对钢的微观组织和电磁性能的影响,以便为工业化生产制定更为合理的硫含量控制标准和采取更为有效措施减轻炼钢生产的硫含量控制压力,结合0.25% Si 无取向硅钢 ,采用非水溶液电解提取 + 扫描电镜/透射电镜观察相结合的方法 ,研究了0.006 8%、0.010 2%、0.025 5% 和 0.035 3% 硫含量条件下,钢中的硫化物夹杂物组成和存在形式及其形貌、种类、尺寸、数量变化,以及相应的热轧、成品试样的微观组织和电磁性能变化。结果表明,随着钢中硫含量的增加,钢中的硫化物逐渐由 MnS→MnS+Cu2S→Cu2S转变,数量逐渐增多,尺寸向高低两个方向发展。相应地,导致热轧再结晶组织劣化和抑制了成品晶粒尺寸长大。随着钢中硫含量的增加,钢的磁感、铁损劣化程度逐渐增大。钢中的硫含量平均每增加 0.01%,涡流损耗、磁滞损耗分别劣化0.24 W/kg 和 0.41 W/kg,而磁感会劣化 0.009 T。但是 ,在硫含量为 0.010 2% 时 ,铁损可以低于 6.0W/kg,而在硫含量为 0.025 5% ... In order to find out the precipitation behavior of sulfide inclusions and the corresponding changes of microstructure and electromagnetic properties of high sulfur silicon steel sheets, so that to design more suitable sulfur concentration controlling limit for industrial manufacture and to release the steel-making difficulty effectively, Based on the change of given sulfur concentration 0.006 8%, 0.010 2%0.025 3% and 0.035 3%, the type and composition, the size and number, and the size distribut...
电力变压器用高磁感取向硅钢的发展及应用
阐述了国内外高磁感取向硅钢的生产研究水平与发展趋势,包括通过提高高斯晶粒取向度、细化磁畴、涂覆张力涂层、减薄钢片厚度进一步降低铁损以及低温加热技术和短流程技术新工艺。分析高磁感取向硅钢在我国大型电力变压器上的应用情况,结果表明,发展更薄规格高磁感、低铁损、低磁致伸缩取向硅钢可为大型变压器的安全性、节能性及环保性提供有效保障。 The research progress and development trend of high magnetic induction grain-oriented silicon steel at home and abroad are summarized,including the technology of improving the Goss alignment,refining domain wall,adding stress coating,decreasing thickness of sheet,and the new technique of reducing heating temperature of casting slab and shortening operational.Moreover,the application of high magnetic induction grain-oriented silicon in power transformer is presented.Developing grain-oriented sili...
退火温度对双辊连铸无取向硅钢组织的影响
利用光学显微镜、TEM和EBSD研究了退火温度对双辊连铸无取向硅钢再结晶组织的影响。结果表明,900℃退火后组织分布不均匀,有大量带状组织,平均晶粒尺寸29.5μm。提高退火温度,晶粒尺寸增大,组织均匀化程度增加,1050℃退火时,带状组织基本消失,平均晶粒尺寸42.2μm。 Effect of annealing temperature on recrystallization microstructure of non-oriented electrical steel produced by twin-roll casting process was investigated using OM,TEM and EBSD.The results show that the recrystallization microstructure is uneven because of many banded grains existing,average grain size is 29.5 μm.With annealing temperature increasing,the recrystallization grain size increases,microstructure becomes more homogeneous.When 1050 ℃ annealing,the banded structure almost disappear and...
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...
冷轧大压下量下新型无取向电工钢的退火组织演变
研究了冷轧大压下量,950℃退火时间对一种新型含铜无取向电工钢晶粒度和织构的影响。结果表明,大压下量冷轧,随压下量的增加,退火晶粒向γ线聚集,形成强{111}<112>织构。提高冷轧压下率,退火织构{111}<100>,{110}<001>强度减弱,增加退火时间,退火织构{111}<110>,{100}<001>,{110}<001>强度变弱。采用87.5%冷轧压下率和950℃退火60 s,有利织构{100},{110}占有率最大。 The effect of annealing(950 ℃) time with high cold rolling reduction on grain size and texture of a new non-oriented electrical steel containing copper was investigated.The results show that for high cold rolling reduction,most annealed grains are oriented along γ-fibre with increasing cold rolling reduction ratio and strong texture {111}<112> is formed.With increasing the cold rolling reduction ratio,the intensity of annealed texture {111}<110>,{011}<100> decreases.With increa...