钢厂
热轧加热时间对稀土取向硅钢抑制剂固溶行为的影响
借助OM、激光共聚焦显微镜、质谱仪和电解萃取等设备和方法,研究了添加微量稀土La(质量分数0.001 1%)的取向硅钢在轧制前采用不同加热保温时间对抑制剂固溶行为的影响。结果表明:当稀土取向硅钢在1 250℃分别保温10、20、30 min后,试验钢晶粒尺寸随保温时间延长有先快后慢的长大趋势;三种抑制剂元素Mn、Cu和Al均发生固溶,保温时间对Mn和Cu两种元素的固溶影响明显,固溶量分别由69.8%和43.7%增加至84.2%和85.2%;随着保温时间的延长,稀土取向硅钢中抑制剂的小尺寸未溶物逐渐减少直至消失,较大尺寸未溶物(300~600 nm)逐渐转变为小尺寸未溶物逐步溶入基体中,数量减少且未溶物的类型由复杂逐渐转变为单一。 In this paper the solid solution behavior of the inhibitor under various holding time in 0.001 1 %La oriented silicon steel during reheating had been investigated by using OM, LM, methods of electrolytic extraction and mass spectrometer. The results showed that grain size of the test steel increased significantly with the holding time prolonging when the rare earth oriented silicon steel was heated to1 250 ℃ and held for 10, 20 min and 30 min respectively, and the growth trend slowed down after ...
Si在纯Fe及低硅钢中扩散行为
采用磁控溅射方法,分别在纯Fe以及低硅钢基片上沉积富Si膜,并对其进行真空扩散热处理.通过能谱分析及X射线衍射研究了Si在纯Fe与低硅钢基体中的扩散特征,运用DICTRA软件建立了扩散模型.研究发现Si在纯Fe基体中扩散时发生γ-Fe(Si)→α-Fe(Si)相转变,扩散速率受控于相界面的迁移.当沿截面Si含量梯度不足以驱动相界面正向迁移时,延长扩散时间会发生相界面回迁现象,最终趋于单一相内均匀化扩散过程.Si在低硅钢基体中的扩散符合Fick扩散第二定律. Si-rich films were deposited on pure iron and low-Si steel substrates by direct current magnetron sputtering,and then were subjected to vacuum annealing.The distribution characteristics of Si across Fe and low-Si steel substrates were studied by energy spectrum analysis(EDS) and X-ray diffraction(XRD).DICTRA software was used to simulate the diffusion models.It is found that the diffusion behavior of Si in the Fe substrate is from γ-Fe(Si) phase to α-Fe(Si) phase and the rate of diffusion is con...
大压下率冷轧无取向硅钢再结晶织构演变
研究了冷轧95%变形量无取向硅钢不同退火温度(710~1 050℃)下再结晶织构特征.再结晶刚完成时(710℃退火),呈现强γ({111<112>~<134>)与弱{114}<481>织构特征;随退火温度升高至900℃,γ明显减弱,{114}<481>组分持续增强,形成典型的{h,1,1}<1/h,1,2>织构;进一步升温至1 050℃,再结晶织构不再发生明显变化.基于EBSD分析,{114}<481>组分的持续强化可归因于其明显的尺寸优势以及较高频率的高能晶界(取向差角为20°~45°). A non-oriented silicon steel was heavily rolled to 95% reduction and subsequently annealed at 710~1 050 ℃ to investigate recrystallization texture evolution.When annealed at 710 ℃ with complete recrystallization,the texture is characterized by a strong partial γ fiber spreading from {111}<112> to {111}<134> and a weak {114}<481> component.As annealing at 900 ℃,γ fiber is decreased significantly while {114}<481> is increased consistently,producing a typical {h,1,1}<1/h,...
TSCR热轧工艺对3.2%Si无取向硅钢组织性能的影响
研究了薄板坯连铸连轧流程(TSCR)条件下热轧工艺对3.2%Si-0.7%Al无取向硅钢组织、织构演变及磁性能的影响规律。结果表明,提高均热温度和热轧温度有助于获得粗大的变形组织和强烈的{001}〈110〉织构,进而对后续的组织、织构演变进程及磁性能产生有利的遗传影响。与低温均热和低温热轧相比,高温均热和高温热轧得到的最终成品板的再结晶晶粒较粗大,λ纤维再结晶织构较强而γ纤维再结晶织构较弱,磁感应强度较高。 It was investigated that the effects of thin slab cast rolling(TSCR) hot rolling processes on microstructural,textural evolution and magnetic properties of 3.2%Si-0.7%Al non-oriented silicon steel.The results show that much larger hot rolling deformed microstructure and much stronger {001}〈110〉 texture could be obtained by increasing the soaking and hot rolling temperatures,which had good heritable effects on subsequent microstructural,textural evolution and magnetic properties.The final sheets ...
RH精炼工艺对无取向硅钢MgO·Al_2O_3夹杂物演变影响及控制
基于BOF→RH→CSP生产工艺,研究了RH精炼过程钢中夹杂物类型演变及MgO·Al2O3夹杂物形成规律,同时对MgO·Al2O3夹杂物的形成条件进行了热力学计算,借助CFD数值模拟软件研究了RH精炼过程卷渣行为。研究发现,RH精炼过程20和30 min时,w([MgO])/w([Al2O3])为0.005~0.020,未发现MgO·Al2O3夹杂物;RH出站后夹杂物w([MgO])/w([Al2O3])为0.3~0.5,且RH精炼结束后MgO·Al2O3夹杂物占夹杂物总量的58.4%;另外,RH精炼过程钢液表面速度CFD模拟结果为0.57 m/s,大于临界卷渣速度0.45 m/s,且顶渣成分与夹杂物成分相近,存在卷渣现象。热力学计算表明,钢液与炉渣平衡时钢中w([Al])为0.31%~0.37%,w([Mg])为0.00024%~0.00028%,在MgO·Al2O3生成区域之内。减少RH处理过程卷渣,浇铸过程下渣及控制顶渣和包衬相中MgO质量分数可抑制MgO·Al2O3夹杂物形成。 Based on the practical production of non-oriented silicon steel, the evolution of inclusion type and the formation of MgO·Al2O3inclusion were analyzed in the process of BOF→RH→CSP. The thermodynamic conditions for forming MgO·Al2O3inclusion were discussed and the behavior of slag entrapment of molten steel was also simulated by CFD software during RH refining. The results showed that the value of w([MgO])/w([Al2O3]) was in the range of 0.005-0.020 and no MgO · Al2O3 inclusion was observed at 20 ...
稀土元素Ce含量对50W470无取向硅钢显微组织及性能的影响
利用光学显微镜(OM)和扫描电镜(SEM)研究了不同稀土Ce含量的50W470无取向硅钢的铸坯、热轧板和冷轧退火板的宏观和微观组织,并采用磁性能测试仪测定其磁性能。结果表明:当稀土Ce的加入量从0增加到66×10-6(质量分数)时,铸坯的柱状晶平均宽度从3.82 mm减小到3.24 mm,等轴晶率从43.1%增加到51.3%;热轧板的平均晶粒尺寸逐渐增加,从26.2μm增加到33.3μm,再结晶百分数从24%增加到37%;退火板的平均晶粒尺寸从36.2μm增加到39.3μm;磁性能测试表明,微观组织的变化有利于50W470无取向硅钢铁损降低和磁感提高。 Macro-structure and microstructure of as-cast plate, hot rolled plate and cold rolled annealed plate of 50 W470 non-oriented silicon steel with different rare earth Ce content was studied by optical microscope(OM) and scanning electron microscopy(SEM), and their magnetic properties were measured by magnetic property tester. The results show that when the addition amount of rare earth Ce increases from 0 to 66×10-6(mass fraction), the average width of columnar crystal of the as-cast pl...
低温取向硅钢高温退火抑制剂的演化
取向硅钢利用析出物作为抑制剂,抑制初次再结晶晶粒的长大,抑制剂是取向硅钢发生二次再结晶的基本条件之一。文中通过低温板坯加热技术制备取向硅钢,采用透射电镜(TEM)观察并研究了高温退火阶段抑制剂的演化过程。结果表明,渗氮后形成的非晶态Si3N4析出物不稳定,在700~750℃退火升温阶段转化为(Al,Si)N;(Al,Si)N颗粒在800℃发生团聚,随后长大并粗化;(Al,Si)N是低温取向硅钢主要抑制剂,随退火温度的升高,(Al,Si)N抑制力大幅下降。 Precipitates as inhibitor are used to inhibit the grain growth of primary recrystallization in grain-oriented silicon steel,and inhibitor is one of the basic conditions for occurring of secondary recrystallization.The grain-oriented silicon steel was produced by low temperature slab heating and nitriding technique.The evolution of inhibitor was observed by transmission electron microscopy.The results show that Si3N4 particles are precipitated after nitriding,and Si3N4 particles are amorphous and...
无取向电工钢硫含量控制技术研究
针对采用含钒铁水生产无取向电工钢存在的铁水脱硫率低、转炉冶炼过程回硫量大、成品硫含量偏高的问题,通过对含钒钛铁水脱硫,减少转炉冶炼过程回硫以及RH脱硫技术等方面的研究,大幅度降低了电工钢成品硫含量。生产表明钢中w(S)=0.001 9%~0.006 9%,平均为0.004 2%;w(S)≤0.008%的比例达到了100%,且w(S)≤0.005%的比例也达到了91.43%。 In cognizance of the problems of low desulphurization rate for hot metal,large sulfur-recovery in converter as well as high sulfur content in products in producing non-orientation electrical steel with vanadium-content hot metal countermeasures have been carried out.Sulfur content in non-orientation electrical steel is decreased obviously by way of study on technologies of desulphurization for hot metal with vanadium & titanium,sulfur-recovery control in converter and desulphurization in RH ...
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...
钙处理对无取向硅钢中非金属夹杂物的影响
采用电解法和扫描电镜研究了300 t转炉-RH精炼钙处理对无取向硅钢板(%:≤0.005C、1.2~2.2Si、0.2~0.6Mn、≤0.20P、≤0.005S、0.2~0.6Al、0~0.01Ca)中夹杂物的影响。结果表明,钢中Al含量为0.25%和0.35%时,钢中溶解氧均小于1×10-4%,钙处理后都会产生CaS夹杂物,尤其是含0.35%Al的钢水;钙处理可以有效减少钢中的夹杂物数量,尤其是0.5μm以下的微细夹杂物数量;钙处理后夹杂物的种类以AlN、CaS为主,同时还含有少量的氧化物夹杂物以及AlN-CaS复合夹杂物,尺寸主要为1.5~5.0μm。 The effect of 300 t converter-RH refining calcium treatment on inclusions in non-oriented silicon steel sheet (%:≤0.005C,1.2~2.2Si,0.2~0.6Mn,≤0.20P,≤0.005S,0.2~0.6A1,0~0.01Ca) has been studied by electrolysis and scanning electron microscope.Results show that with 0.25%and 0.35%Al content in steel,all the dissolved oxygen in liquid is less than 1×10-4%,and the CaS inclusions are produced after calcium treatment,especial for the liquid containing 0.35%Al;the amount of inclusions in ste...
水氯镁石制备硅钢级氧化镁
以水氯镁石为原料,采用氨法沉镁-煅烧-添加剂的方法制备硅钢级氧化镁。考察了反应温度、反应pH值、陈化时间对中间体氢氧化镁纯度及转化率的影响;研究了煅烧温度和煅烧时间对氧化镁水化率的影响及添加剂的量对氧化镁悬浮性能的影响。控制实验条件为:反应温度55℃,pH值为9.5,陈化时间2h,煅烧温度1050℃,煅烧时间2h,添加剂量为0.8%,制得氧化镁的纯度为98.99%、水化率为2.92%、悬浮性能为3mm/h,达到硅钢级氧化镁的要求。 Using bischofite as raw material,the preparation of magnesium oxide with silico-steel grade was studied.The effects of reaction temperature,reaction pH value and aging time on the intermediate magnesium hydroxide purity and conversion rate were studied.Calcinations temperature,calcinations time relationship to the hydration rate of MgO and amount of additive to the suspension performance of MgO were investigated.The results indicated that the optimum technological conditions were as follows:reac...

