钢厂
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...
退火工艺对3.15%Si冷轧无取向硅钢组织和织构的影响
试验研究了退火温度(850~950℃)和时间(5~18 min)对2.3 mm热轧硅钢板(/%:0.036C,3.15Si,0.21Mn,0.005P,0.007S,0.032A1)6道次轧制的0.35 mm冷轧板组织和织构的影响。结果表明,退火温度越高,晶粒平均尺寸越大,900℃5 min退火时平均晶粒尺寸41.39μm,试样织构主要集中在γ取向线上的{111}<112>织构组分和{111}<110>织构组分;900℃18 min退火时平均晶粒尺寸为48.08μm,试样的{111}面织构和{112}面织构密度都明显减弱,{001}面织构增强,磁性能较优。 The effect of annealing temperature(850 ~950 ℃) and holding time(5 ~ 18 min) on structure and texture of 0.35 mm sheet by 6 passes cold-rolling from 2.3 mm hot-rolled plate of silicon steel(/%:0.036 C,3.15 Si,0.21 Mn,0.005 P,0.007 S,0.032A1) has been tested and studied.Results show that the higher the annealing temperature the coarser the average grain size;As annealing at 900 ℃ for 5 min the average grain size of steel sheet is 41.39 μm,and the texture in sample is mainly concentrated in y orie...
修正GTN模型及其在预测硅钢冷轧边裂中的应用
考虑剪应变对微孔洞损伤演化的影响,对GTN损伤模型的损伤演化机制进行修正,建立了适用于不同应力三轴度水平的损伤模型。结合隐式应力更新算法和显式有限元计算,采用VUMAT子程序实现了修正GTN模型在有限元软件ABAQUS中的数值计算。通过模拟纯剪切和剪切-拉伸两组试样的损伤演化和断裂行为,验证了修正GTN模型在不同应力三轴度承载条件下的有效性。运用修正GTN损伤模型模拟含边部缺口的带钢在轧制过程中裂纹的萌生和扩展行为,模拟结果与实验相一致,表明该模型可有效地用于带钢缺陷在轧制过程中扩展行为的分析和预测。模拟和实验结果表明,带钢边部缺口在轧制过程中,缺口前沿和后沿均会萌生裂纹,且后沿裂纹扩展更为明显。 Considering the effect of shear strain of micro-void on damage evolution, a modified GTN model applicable to various stress triaxiality conditions is proposed by modifying the damage evolution mechanism of the GTN damage model. The modified model is implemented in commercial finite element software ABAQUS by combining the implicit stress update method with an explicit finite element solving algorithm and through the user-defined material subroutine VUMAT. The damage evolution and the failure pro...
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...
电动汽车电机用电工钢疲劳性能测试技术研究
电动汽车电机在高速旋转时承受离心力和电磁力的作用,在进行电机转子设计时,既要考虑电磁性能,还要考虑机械性能。对电机转子受力情况进行了综述,分析了转子用电工钢疲劳性能参数的重要性,详细阐述了试样抛光、表面处理、试样的对中和安装对测试结果的影响。 The motor of electric vehicle bears big force for high speed rotors,mainly including centrifugal and electromagnetic forces.The magnetic and mechanical aspects of the electrical steel are crucial to machine design.In this paper,the forces applied on the motor were summarized and importance of fatigue properties was analyzed.The influence of specimen polish,surface treatment,alignment and installation on fatigue testing result were represented in detail.
无抑制剂取向硅钢概述
概述了无抑制剂法生产取向电工钢的特性及其用途;总结无抑制剂生产取向电工钢的原理及工艺方案.重点讨论了成分方案,即元素对磁性能的影响和最终高温退火方案对二次再结晶的影响.研究结果表明,无抑制剂取向硅钢化学成分范围没有普通取向硅钢和高磁感取向硅钢严格,提高了成材率;最终高温退火决定了二次再结晶的好坏,从而最终决定成品磁性能,最佳的高温退火温度在850～950℃之间. This article provides an overview on the characteristics and uses of inhibitorless process producing grain-oriented electrical steels.The mechanism of inhibitorless process and technology programs were discussed.The results show that the chemical composition and final annealing were determined according to magnetic properties.The inhibitor-free grain oriented silicon steel has loose range of chemical composition;Secondary recrystallization occurs mainly in the final annealing and the best anneal...
Fe-6.5%Si高硅钢的性能及制备技术
Fe-6.5%Si高硅钢是一种具有高磁导率、低矫顽力和低铁损等优异软磁性能的合金,但是其室温脆性和低的热加工性能严重影响了其在工业领域的应用。综述了Fe-6.5%Si高硅钢的性能,评述了合金的改性法、特殊轧制法、快速凝固法、沉积扩散法、粉末冶金法等制备工艺。 It is well known that 6.5%Si high silicon steel is one kind of soft magnetic materials with higher re-lative permeability,lower coercive force and iron loss than those of conventional industrial silicon steel.However,their room-temperature embrittleness and poor workability limit their practical applications in the industry.The pre-paration technique such as modification treatment on alloy,special rolling,rapid solidification,CVD and powder me-tallurgy is reviewed.
高磁感取向硅钢涂层技术
涂层技术在高磁感取向硅钢生产中起着重要的作用.根据生产实践,介绍了高磁感取向硅钢生产中涂层的种类和作用、涂料的成分和对产品性能的影响、涂层工艺质量控制要点和检验方法等,并提出了通过优化涂层工艺改善高磁感取向硅钢性能和外观质量的方法. Surface coating technique plays an important role in producing high magnetic inductivity grain-oriented silicon steel.Based on production practice,this paper describes the types and function of the coating,the composition of the coating and its effect on the product performance,the quality control and inspection method for the coatings,as well as proposes ways to improve the magnetic property and surface quality of the steel by optimizing the coating process.
