钢厂
无取向硅钢热轧边裂的形成原因
利用加热炉模拟、动态再结晶以及热模拟等试验方法以及扫描电镜、金相显微镜等分析观察手段对无取向硅钢边裂的成因进行了探讨。结果表明,长时间加热使得板坯边部晶粒异常长大,晶界氧化并脱碳,轧制过程中边部温度过低,动态再结晶过程变弱,使得板坯边部延伸性能变差,是导致硅钢边裂的主要原因。建议通过适当降低铸坯加热温度、缩短保温时间、提高终轧温度来改善硅钢边裂缺陷。 The behaviors of high temperature oxidation,dynamic recrystallization,and hot ductility,microstructure evolution were investigated on the non-oriented electrical steel sheets to discuss the formation of edge crack.The key causes of cracking was found to be the coarse as-cast microstructure,grain boundary oxidation and decarburization in reheating furnace,as well as reduced temperature at strip edge region during hot rolling process resulting in reduced hot ductility and lack of enough dynamic re...
在动态热处理条件下对取向电工钢二次再结晶的研究
对应用动态加热进行短时温度退火的取向电工钢进行了二次再结晶研究。所进行研究的实验用取向电工钢是经过终冷轧和后续罩式退火后的一条工业化生产线生产的。研究结果表明,运用短时热处理条件可引起研究钢完全的异常晶粒长大。在实验室处理的材料的织构和金相组织与工业化生产的经过终退火而获得的相同的取向电工钢类似。但是,在实验室处理的取向电工钢的二次再结晶的矩阵中可观测到\"寄生\"晶粒。从磁性观点看,这些\"寄生\"晶粒含有不理想的{111}取向织构。 The present study was made to investigate secondary recrystallization in grain-oriented steels annealed at short time temperature exposures with application of dynamical heating.The investigated GO(Grain Oriented) steels for experiments were taken from one industrial line after final cold rolling reduction and subsequent box annealing.It was shown that application of short time heat treatment conditions could lead to complete abnormal grain growth in the investigated GO steel.The texture and mic...
常化工艺对Si的质量分数为1.6%的无取向电工钢磁性能的影响
研究了常化温度、常化时间及常化后冷却速度对Si的质量分数为1.6%的无取向电工钢成品磁性能的影响。结果表明:在850~1 050℃范围内,随着常化温度的升高,成品铁损先减小后增大,成品磁感应强度先增大后减小;当常化温度为1 000℃时,成品平均铁损最低,平均磁感应强度最高;常化时间从3min延长到7min时,成品铁损先减小后增大,成品磁感应强度则呈单调下降趋势;随着常化冷却速度的降低,成品铁损先减小后增大,成品磁感应强度则呈单调增大趋势;对于Si的质量分数为1.6%的无取向电工钢,最佳的常化制度为:在1 000℃进行常化,时间5min,常化后空冷。对热轧板进行常化后,热轧板发生了不同程度的再结晶和晶粒长大。提高常化温度、延长常化时间、降低冷却速度,都能使常化板晶粒粗化,进而粗化成品板晶粒,改善磁性能。通过扫描电镜观察发现,成品板中析出物主要为AlN和MnS的复合析出物,以及少量的单独析出的AlN和MnS,而常化工艺主要是通过粗化析出相,减少细小析出相数量,从而减少对晶界钉扎作用来改善成品磁性能。 The effects of normalizing temperature,normalizing time and cooling rate after normalizing on magnetic properties of non-oriented electrical steel with mass fraction of Si of 1.6% were investigated.The results show that core loss of product decreases first and then increases,while magnetic induction increases first and then decreases with the increase of normalizing temperature from 850 to 1 050℃.Average core loss of product is the lowest and average magnetic induction is the highest when normal...
新型无取向电工钢在退火过程中组织和织构取向的演变
通过金相分析和电子背散射衍射技术研究了一种新型含铜无取向电工钢在950℃退火不同时间(3~180s)空冷后的组织和织构取向的演变。结果表明:该钢在退火3s时的主要织构为α和γ线织构,{100}<110>织构最强;退火20s时织构以<111><112>、{111}<110>、{112}<110>、高斯织构和立方织构为主,随着退火时间的延长,高斯织构和立方织构强度呈减弱趋势;合理控制保温时间有利于提高{100}、{110}面织构的占有率。 Evolution of microstructure and texture oriented of a new non-oriented electrical steel during annealing at 950℃for different times(3-180) s and air cooling was studied by metallography and electron back-scattering diffraction analysis.The results show that after annealing for 3 s most of the texture oriented alongα-fibre andγ-fibre,the intensity of {100}〈110〉was the strongest.{111}〈112〉,{111}〈110〉,{112}〈110〉,Gauss texture and cube texture were the main texture after annealing for 20 s,with the ...
不同尺寸电工钢样品磁性能检测对比分析
对CSP流程生产的无取向电工钢M50W800不同尺寸样品的磁性能进行了测试和分析,结果表明:采用不同单片检测的磁性能结果与标准的Epstein方圈样品检测对比,存在明显的偏差;且同一尺寸的单片纵横向样品之间相比较,对应的磁性能差异性也较大。几种不同尺寸的单片样品,以320mm×30mm尺寸的纵横向平均值最接近标准Epstein方圈样的性能值,其铁损偏差最小。 The magnetic properties of M50W800 non-oriented electrical steel produced by CSP process were tested and analyzed with samples of different sizes,showing that significant deviation existed compared to that of Epstein square circle sample.In particular,obvious difference in magnetic properties also existed between longitudinal and transverse samples of the same size.For test samples of different sizes,the average magnetic properties of 320mm×30mm samples are the closest to that of Epstein square ...
罩式炉常化工艺对热轧硅钢50W350组织和性能的影响
研究了罩式炉常化工艺对50W350硅钢热轧板组织、夹杂物和性能的影响。研究结果显示,罩式炉常化工艺在温度一定的情况下,随着保温时间延长,硅钢晶粒逐步再结晶并长大,同时析出物也在聚集长大。通过制定合理的罩式炉常化工艺,可以实现硅钢晶粒的再结晶和长大,从而达到连续退火炉常化工艺产品技术要求。 The influence of normalization process with a bell furnace on the structure,inclusions and properties of 50W350electrical steel hot-rolled sheet was studied.The research results showed that:when the steel was normalized at a certain temperature in the bell furnace,the silicon steel grains gradually recrystallized and grew up with the extension of the annealing holding time,and at the same time,the precipitates also gathered and grew up.The recrystallization and growth of the silicon steel grains...
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...
异步轧制硅钢的表面纳米化及轧制参数的影响
对硅钢板材分别进行异步和同步轧制,研究了轧制参数包括速比、压下量和道次对板材表面显微组织的演变的作用.结果表明,异步轧制硅钢板材表面形成了晶粒尺寸为10~50 nm,取向接近随机分布的纳米晶,而同步轧制板材的表面只形成了位错胞,证明异步轧制可以诱发表面纳米化.异步轧制板材表面纳米晶的形成过程为:在剪切力的反复作用下,高密度位错形成、滑移、湮灭和重组形成亚微米尺度的亚微晶/位错胞.随着压下量和轧制道次增加,高密度位错重复以上过程使晶粒尺寸减小、取向差增大,最终形成取向接近随机分布的纳米晶组织.大压下量和多道次是异步轧制诱发板材表面纳米化的关键,而速比的增加可以加快纳米化进程. Surface nanocrystallization(SNC) can effectively enhance the surface and global properties of the metallic materials,such as microhardness,intensity,fatigue,wear and corrosion resistances,therefore provides more promising practical industrial applicability.Up to now,several SNC treatment methods were developed based either on the principles of ball impactions or friction sliding,however,difficulty still exists for the surface treatment of large-dimensional samples with high efficiency.Recently,m...
火花源原子发射光谱法在线测定电工钢中的超低碳
采用火花源原子发射光谱分析测定电工钢中超低C,研究试样制备方法、Ar纯度和压力等条件对分析结果的影响,并对工作曲线进行了优化,实现了一次分析同时测定电工钢的多种元素,满足炉前和精炼在线分析的要求。 Ultra-low carbon in electrical steel is determined with spark-source atom emission spectrum.It is researched the influence of sample making method,purity of Ar,and pressure on analysis result.The work curve is optimized.The determination of many elements in electrical steel only in one analysis is realized.It meets demands of on-line analysis for blast furnace and refining.
无取向电工钢边部减薄控制技术研究
叠片系数是冷轧无取向电工钢的重要质量指标。为了提高叠片系数,必须保证无取向电工钢板形良好以及横向厚差小。针对攀钢冷轧厂4机架HC轧机轧制无取向电工钢的边部减薄问题,以无取向电工钢横向厚差最小作为目标函数,建立了一套针对无取向电工钢边部减薄控制的辊型曲线优化数学模型,开发了无取向电工钢专用辊型曲线,使无取向电工钢横向厚差从25μm降低到10μm以下,取得了良好的控制效果。 The lamination factor is an important quality index of non-oriented silicon steel strip.Considering the lamination factor,the non-oriented silicon steel must have a good shape and a smaller transverse thickness difference.In order to solve the edge thinning of non-oriented silicon steel strip in Panzhihua Steel,a mathematic model for designing the roll shape is built.In the model,the transverse thickness difference of non-oriented silicon steel strip is taken as the objective function.Based on t...
硅钢高温氧化铁皮的显微结构表征
利用电子探针面分析、状态分析及电子背散射衍射相分析技术研究硅钢高温氧化铁皮的显微结构。电子探针面分析可以直观的看出元素的分布状态,初步判断氧化铁皮的结构,而状态分析可以准确表征常规氧化铁皮中铁元素的状态,对于合金元素富集区域则通过电子背散射衍射相分析技术来标定。结果表明,高温氧化铁皮的结构主要有4层,即最外层为厚度约为10μm的Fe2O3相,次外层为Fe3O4相,中间层为FeO相上分布有颗粒状的Fe3O4相,最内层为FeO相和Si元素富集的Fe2SiO4相。其中Fe2SiO4层的分布特征与加热温度密切相关:1 100℃时,Fe2SiO4相呈颗粒状,弥散分布在FeO层;1 200℃时,Fe2SiO4相呈液态,侵入基体和疏松的FeO层,且沿着FeO晶界呈网状分布。 The microstructure of high temperature oxide scale on silicon steel was characterized by electron probe microanalyzer(EPMA)mapping analysis,state analysis and electron backscatter diffraction(EBSD)phase analysis.The element distribution and the initial structure of the oxide scale could be detected by EPMA mapping analysis apparently.And the state of iron in the conventional oxide scales could be determined by state analysis.Meanwhile,the alloy-rich region could be identified by EBSD phase analy...

