钢厂
冷轧无取向硅钢表面麻面缺陷成因分析及其控制措施
针对某厂DMS森吉米尔轧机生产无取向硅钢表面麻面缺陷的问题,根据生产实际,对其形成原因从乳化液及工作辊两方面因素进行了分析。结果表明:乳化液对麻面缺陷的产生有一定影响,但不是主要因素,主要原因是由于二十辊森吉米尔轧机工作辊辊径较小,轧制相同长度带钢轧辊运转周期较大,容易产生疲劳失效而导致。为此,提出通过调整冷轧工序成品轧制道次的压下率以减小轧制力,从而减小工作辊的磨损疲劳;通过对轧制乳化液浓度、温度的合理控制,以改善润滑效果、提高轧制速度,而进一步缓解轧辊疲劳的改进措施,使该钢厂无取向硅钢麻面缺陷发生率由原来的18%降至0.8%,带钢表面质量明显改善。 For the problem of surface pockmarks of non-oriented silicon steel strip produced by a DMS Sendzimir mill, based on the production practice, the formation causes were analyzed from two aspects of emulsion and working roll. The results show that the emulsion has a certain effect on the formation of surface pockmarks defects, but it is not the main factor. The main reason is that the working roll diameter of the 20-high Sendzimir mill is small, and the running period of the roll rolling the same l...
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...
电工钢极薄带生产现状及市场应用
介绍了国内、外电工钢极薄带的生产现状及市场应用的情况,以及典型生产企业的生产规模、产品性能和应用领域,指出扩大高牌号无取向电工钢生产、提高产品质量是目前电工钢发展的迫切要求。 The production situation and market application of ultra thin electrical steel strip at home and abroad were described.The production capability,product property and application area of typical corporation were introduced.The results indicate that the urgency needed of electrical steel development is expanding high-grade non-oriented electrical steel production and improving products quality at present.
单道次热轧对Fe-1.5Si硅钢氧化层形貌的影响
将Fe-1.5Si硅钢试样分别在1 000~1 200℃空气条件下氧化30 min,观察发现在1 000℃和1 100℃时,氧化层与基体界面处存在硅酸亚铁,而当温度为1 200℃时,硅酸亚铁不但存在于界面处,同时也存在于氧化层中.将各温度下得到的带有氧化层的试样进行单道次热轧试验,压下率分别为10%和30%,发现1 000℃和1 100℃时,较高的压下率使氧化层破碎更加严重,但是单道次热轧未能改变氧化层的结构;当温度为1 200℃时,由于液态的硅酸亚铁的出现,单道次热轧能够将界面处的液化的硅酸亚铁层挤压到氧化层中,消除了硅酸亚铁层的钉扎基体的效应,改善了氧化层与基体界面的平直度. Specimens of Fe-1.5Si silicon steel were oxidized at 1 000 ~ 1 200 ℃ in air for 30 min.At 1 000 ℃ and 1 100 ℃ fayalite was observed at the scale/substrate interface.While at 1 200 ℃fayalite was found both at the scale/substrate interface and at the outer oxide layer.Then after the single-pass hot rolling process,with the compression ratio of 10% and 30%,it was found that at 1000 ℃ and 1 100 ℃,higher compression rate accelerated the broken of the scale layers,but the scale structure was not affec...
铸坯热装温度对无取向硅钢中AlN和MnS析出行为的影响
通过固溶度积公式计算及热模拟实验,对不同热装和加热温度条件下的无取向硅钢铸坯中析出相进行了研究.在低于950℃热装时,铸坯中AlN的析出量和尺寸不再变化,但MnS和AlN-MnS的数量及平均尺寸随着热装温度降低而进一步增加,并在温度低于600℃时达到最大值后保持不变.与1200℃相比,1100℃加热的铸坯中AlN、MnS的总固溶量相对更少.相比850℃热装,600℃热装再加热到1100℃的铸坯中AlN和MnS的总固溶量更少,且AlN和MnS尺寸更大.合适的热装温度和加热温度分别为600℃和1100℃. Based on solubility product calculation and thermal simulation experiments,precipitated phases in continuous casting slabs of non-oriented silicon steel were systematically studied at different hot charging and heating temperatures.When the hot charging temperature is below 950 ℃,the content and size of AlN remain unchanged,but the quantity and size of MnS and AlN-MnS increase when the hot charging temperature decreases,reach maximum and remain unchanged when the hot charging temperature is belo...
电子探针波谱仪定量测定硅钢中硅含量结果的不确定度评定
依据GB/T 15616—2008《金属及合金的电子探针定量分析方法》,采用电子探针波谱仪对某W600硅钢中的硅含量进行了定量测定,对影响其定量测定结果的不确定度分量进行了分析,并对不确定度的各个分量进行了计算和合成,最后给出了硅钢中硅含量测定结果的不确定度报告:该硅钢中的硅含量(质量分数)为1.50%,扩展不确定度U=0.20%,取包含因子k=2。 According to GB/T 15616-2008\"Quantitative Method for Electron Prohe Microanalysis of Metals and Alloys\",the quantitative results of Si content in some W600 silicon steel was measured hy EPMA-WDS.The uncertainty components which might affect the measurement results were considered,calculated and synthesized. Finally the uncertainty result for the quantitative value of Si content in the silicon steel was got.The mass content of Si was 1.50%,and expanded uncertainty U=0.20%under the condition of co...
无取向硅钢热轧卷结疤缺陷产生的原因及控制
针对不同牌号的无取向硅钢产生结疤缺陷的难易程度和表面结疤缺陷的外形特征及分布规律,分析了该缺陷产生的原因。通过调整剪前导板的对中度,设置精轧侧导板开度余量及短行程数值,及时修补与更换侧导板,减少带坯与侧导板挤撞程度,有效地降低了结疤缺陷发生率。 This article analyses the cause of the scab defects according to the defects appearance characters and distribution law,degree of difficulty to form scar of non-oriented silicon steel. It can effectively decrease the scabs by different methods,such as adjusting the center line of guide plate,setting the opening margin and short stroke value of the side guide on finishing mill,timely repairing and replacing of side guide,decreasing the collision between the strip and side guide.
无取向硅钢铬酸镁绝缘涂层高温固化工艺
为了确保硅钢铬酸盐涂料的环保性,需要严格控制涂料的固化工艺,保证涂料固化过程中涂料中的六价铬充分转化为三价铬。对涂料及原料进行热重分析(TG)及差示扫描量热法分析(DSC)。结果表明,MgO与铬酐混合转化为MgCrO4,使六价铬稳定性增强,其中大部分Cr6+转变为Cr3+发生在620~700℃,在450~500℃高于铬酐发生大量失重,因此必须加入还原剂保证涂料中六价铬被充分还原;超过360℃后树脂会发生分解,因此实际板温不能超过360℃;加入了还原剂的整体涂料的失重温度区间主要在260~320℃,因此涂料固化时钢板的实际温度最佳区间为320~360℃。 Because of the silicon steel chromate coating’s environmental requirements,the paint curing process must be controlled strictly to ensure all Cr( Ⅵ) transforms to Cr( Ⅲ). The TG and DSC analyses of the paint are studied. The reaction of MgO and CrO3 would generate MgCrO4,enhancing the stability of Cr( Ⅵ). The most r( Ⅵ) in MgCrO4 changes to Cr( Ⅲ) at 620-700 ℃,while the CrO3 has a large weight loss at 450-500 ℃. The reductant must be added in the paint to make sure the Cr( Ⅵ) could transform suf...
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...
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...

