钢厂
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...
钙合金处理硅钢中的夹杂物及晶粒成长变化
采用RH精炼添加钙合金方式对硅钢进行钙处理,结果表明,钙合金添加量为0.67、1.00和1.67 kg/t钢时,钢中Ca含量分别为0、2×10-6和4×10-(6质量分数);随着钙合金添加量的增加,钢中夹杂物粒度逐渐由0～2μm向2～4μm、4～6μm偏移;不同钙处理条件下,钢中均存在粒径小于1μm和粒径为1～5μm的MnS、CuxS夹杂物,后者或单独存在,或与AlN、CaS夹杂复合;钢中粒径为5～10μm的夹杂物基本以Ca的氧化物和硫化物为主。与未经钙处理的炉次相比,钙合金添加量为0.67、1.00和1.67 kg/t钢时,粒径小于1.0μm的夹杂物减少幅度分别为68.06%、87.50%和94.94%。钙合金添加量为1.67 kg/t钢时,可以去除钢中绝大部分的微细夹杂物。 In order to improve the properties of final silicon steels,the calcium treatment was adopted by adding Ca alloys into the liquid steel during the RH refining process.Results show that when the addition of Ca alloys is 0.67 kg/t,1.00 kg/t and 1.67 kg/t,the corresponding Ca content in silicon steels is 0,2 × 10-6 and 4 × 10-6 respectively.With the increase of Ca alloy addition,the particle sizes of inclusions in steels become 2～4 μm and 4～6 μm,from 0～2 μm.Under different calcium treatments,there e...
电工钢热压缩时动、静态再结晶组织及取向分析
采用热模拟方法及EBSD技术,研究Fe-3 wt%Si电工钢在不同温度下组织的动、静态再结晶及晶粒取向特征,特别是少量奥氏体对铁素体动、静态再结晶组织及取向的影响。结果表明,不同温度形变的组织主要分三类:形变长条铁素体、珠光体和等轴细小铁素体。长条形变铁素体内发生动态回复或连续式的动态再结晶,奥氏体周围的铁素体动态再结晶加速,部分以传统的不连续方式动态再结晶。铁素体、奥氏体都可发生静态再结晶。奥氏体的静态再结晶在1050℃以上明显,铁素体的静态再结晶随温度的升高逐渐进行,最显著的再结晶发生在1050℃。不同温度形变的样品,其形变晶粒取向主要以<111>和<100>为主,小等轴铁素体晶粒除与大形变铁素体取向相近外,出现了<110>取向及其它取向。 Static and dynamic recrystallization and grain orientations in a hot-compressed Fe-3 wt% Si electrical steels were studied at different temperatures using Gleeble simulator and EBSD technique,particularly focusing on the effect of small amount of austenite on ferritic microstructure and orientations.The results show that microstructure of the compressed steel,depending on deformation temperature,consisted of elongated and deformed ferrite,pearlite and fine equal-axed ferrite.The elongated ferrit...
电工钢热连轧宽度自适应模型优化及应用
某厂对电工钢的轧制策略进行了优化，粗轧道次由“1+5”改为“1+3”。在优化后的生产过程中，每次变换钢种，烫辊材就会出现窄尺现象，而紧随其后的电工钢板则出现超宽现象。文中针对该问题，介绍了宽度设定模型和宽度自适应模型的原理，阐述了该问题出现的原因及解决方案，并通过对宽度自适应模型的应用研究及优化攻关，有效地解决了问题，大幅提升了实物质量，降低了宽度封锁率。 The rolling strategy of electrical steel was optimized in a factory,and the rough rolling pass was changed from “1+5”to“1+3”.Subsequently,the following problems were occurred in the production process:when the steel grade changed,the roasting roller steel before the electrical steel appeared the narrow width phenomenon,and then the electrical steel appeared the ultra-wide phenomenon.This paper introduced the principle of width setting model and width adaptive model,and expounded the causes and s...
基于GTN损伤模型对含边部缺陷硅钢薄板冷轧时边裂的预测
采用拉伸试验和显微组织观测的方法确定了GTN损伤模型中的9个损伤参数,运用GTN损伤模型对冷轧硅钢薄板边部缺陷的扩展及边裂的产生进行了有限元模拟,并与预置缺口的钢板轧制试验进行对比。结果表明:轧制过程中边部缺陷是造成钢板边部裂纹萌生和扩展的一个重要原因,GTN损伤模型可用来预测含边部缺陷硅钢薄板在冷轧过程中边裂的产生;预测结果与试验结果基本一致。 The crack initiation and propagation of silicon steel strip with edge defect during cold rolling process was studied by using GTN damage model in this paper.Nine damage parameters in GTN model were identified by tensile testing and microstructure observing,and then the FE simulation of edge defect evolution of silicon steel strip during rolling process was conducted on the base of GTN damage model,and then the results were compared with rolling experimental results.The results show that the edge...
钇元素对6.5%Si无取向硅钢组织、高温拉伸及断裂机制的影响
通过微观组织表征、高温拉伸和断口形貌分析,研究了钇(Y)元素对6.5%Si无取向硅钢组织、高温拉伸及断裂机制的影响。研究结果表明,添加Y元素可以在钢液中形成YS和YP的复合析出。YS和YP可以充当异质形核基底,提高形核率,细化凝固组织。热轧组织不均匀,由表层至芯部分别形成等轴晶、等轴晶/拉长晶和拉长晶的混合组织。退火后,热轧变形组织转变为等轴晶,含Y实验钢的退火组织得到明显细化。500℃时效处理后,含Y实验钢具备较低的有序度,300℃的拉伸断口呈现韧性断裂特征,断后伸长率达到20.2%。相反,无Y实验钢发生脆性断裂,断后伸长率仅为2.1%。研究结果证实,Y元素可以通过组织细化和降低有序度提高6.5%Si无取向硅钢的中温塑性。 The effects of yttrium(Y)on microstructure,elevated-temperature tensile properties and fracture mechanism of 6.5% Si non-oriented electrical steel were investigated by means of microstructure characterization,high-temperature tensile test and fracture analysis.The results showed that the doping of Y introduced composite Y-rich precipitates(YS/YP)in the melt.YS and YP precipitates were qualified for heterogeneous nucleation agents,which thus raised the nucleation rate and refined the solidificati...
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...
电解清洗装置在电工钢生产线上的应用
介绍了电工钢生产线连退机组的表面处理工艺,特别是电解清洗系统的工作机理、设备构造、生产工艺及各种影响因素。 This paper introduces the technology of surface treatment of continuous annealing unit in electrical steel production line,in particular the working mechanism,structure of equipment,production techniques and various influence factors of the electrolytic cleaning system.
