钢厂
表面机械研磨/异步轧制无取向硅钢薄带的渗硅行为
对w(Si)=3%无取向硅钢进行表面机械研磨处理(SMAT)和异步轧制(CSR),获得表面纳米结构,再进行550~650℃、4 h固体粉末渗硅处理,用透射电镜(TEM)、扫描电镜(SEM)和X射线衍射仪(XRD)研究表层组织演变。结果表明:经过SMAT后,w(Si)=3%无取向硅钢表面形成了等轴状、取向呈随机分布的、晶粒尺寸为10 nm的纳米晶组织;异步轧制后,表面纳米晶组织保持不变;550~650℃、4 h渗硅处理后,SMAT+CSR样品表面形成化合物层,其厚度随着温度的升高由17μm增加到52μm;化合物层由Fe3Si和FeSi相组成. Nanostructured surface layer was fabricated on a 3%(mass fraction) non-grain oriented silicon steel by means of surface mechanical attrition treatment(SMAT) and cross-shear rolling(CSR),and then a solid powder siliconizing treatment was carried out for the SMAT+CSR sample at 550~650 ℃ for 4 h.The microstructural evolution was examined by using transmission electron microscopy(TEM),scanning electron microscopy(SEM) and X-ray diffraction(XRD).Experimental results show that: equiaxed nanocrystallin...
无铬无取向硅钢涂层烧结固化工艺
为进行磷酸盐系无铬无取向硅钢涂层烧结固化工艺研究,首先对磷酸盐系无铬无取向硅钢涂层进行热重-差示扫描量热(TG-DSC)分析;然后在不同烧结固化温度条件下,测定涂层板温随时间变化曲线;最终获得涂层烧结固化温度与时间(T-t)工艺曲线。通过中性盐雾试验、动电位极化、交流阻抗、涂层附着力以及扫描电子显微镜(SEM)和能谱(EDS)分析验证。结果表明,根据涂层烧结固化温度与时间(T-t)工艺曲线制备的涂层结构致密、性能优异,证明该工艺曲线具有合理性与正确性。 In order to study the curing process of chromium-free non-oriented silicon steel coatings,phosphatic chromium-free non-oriented silicon steel insulating coating was prepared and TG-DSC analysis of the coating was conducted,then the change of the actual temperature of the coated non-oriented silicon steel sheet with time at different curing temperatures was studied. Based on the experiments,the processing curves of curing temperature vs. curing time( T-t) for the chromium-free non-oriented silico...
二次冷轧法与三次冷轧法制备取向硅钢薄带的织构转变规律
本文以热轧常化板为初始材料,采用二次冷轧法与三次冷轧法制备了0.1 mm厚的取向硅钢薄带,测定相应的磁性能,并通过EBSD取向成像技术检测了二次冷轧法与三次冷轧法各工艺过程中织构与组织演变规律。结果表明,采用最终冷轧压下率适中的三次冷轧法,能在冷轧至0.1 mm时保存较多的高斯晶核,使得高温退火后的磁性能明显优于二次冷轧法。最终冷轧压下率通过影响脱碳退火后样品中的{111}<112>织构组分及Goss晶粒数量对最终二次再结晶产生重要影响。 Grain-oriented silicon steel sheets with a thickness of 0. 1 mm were produced from hot-rolled and normalized sheets by two-step-rolling and three-step-rolling methods. Their magnetic properties were measured,and the textures were detected by EBSD technique. The results show that the three-step-rolling method,which has a moderate reduction rate of final cold rolling,can maintain more { 110} < 001 >nucleus,and thus obtaining better magnetic properties compared with the two-step-method. The f...
锌浴中钛对含硅钢Fe-Zn反应的抑制作用
选用Q235和Q345钢,在纯锌浴和含钛量分别为0.05%、0.10%、0.15%、0.20%(质量分数)的合金浴中浸镀0.5、1、3、5、8 min。利用扫描电子显微镜和能谱仪研究了钛对热浸镀锌组织和生长动力学的影响,并提出钛对含硅钢铁锌反应抑制作用的机理。结果表明:钛的加入缩短了Γ的孕育期,促进了合金层中δ的生长和ζ的消失,δ的生长依然受扩散控制,呈抛物线生长规律;Zn-0.05%Ti锌浴可以很好的抑制高硅钢的硅反应性;含硅钢热浸镀锌钛合金浴时,在锌浴中会形成锌铁钛三元T相,该相能吸收ζ晶界处富集的硅,从而抑制了铁锌反应。 Both Q235 and Q345 steels were immersed for 0.5 to 8 min in Zn bath with different amount of Ti,ranging from 0 to 0.20 mass%,for galvanization.The effect of Ti in Zn bath on microstructure and growth kinetics of hot-dip galvanizing coatings on the two steels were investigated by means of SEM and EDS analysis.Base on the experiment,the mechanism of Ti additions in controlling Fe-Zn reaction was proposed.The results show that addition of Ti in the zinc bath decreases the incubation time of Γ phase...
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...
硅钢铸坯再加热过程中夹杂物的析出行为
研究了硅钢铸坯再加热过程中夹杂物的析出行为。采用非水溶液电解提取+扫描电镜观察方法,观察了试样的显微组织,统计了夹杂物的尺寸、种类、数量、分布。结果表明,均热温度为1 523 K时,水淬试样的夹杂物尺寸绝大部分小于0.5μm,0.5~5.0μm的夹杂物数量很少,没有发现5.0μm以上的夹杂物。此外,均热时间为10、30、60、90、120、240 min时,对应试样中0.05~0.2μm的夹杂物数量分别为4.04×104、4.73×104、3.70×104、3.33×104、3.10×104、1.56×104个/mm3。绝大部分夹杂物以MnS、AlN、CuxS类为主,并以三类夹杂物中的两类复合或三类复合居多。三类复合夹杂物总量占每组试样夹杂物总量的90%或以上。随均热时间延长,典型的夹杂物组成会发生如下变化:MnS+AlN+CuxS MnS+AlN AlN。与此同时,MnS、AlN、CuxS三者复合比例从45.2%(均热10 min)降为9.7%(均热240 min)。 The methods of electrolysis extraction from nonaqueous solution and scanning electron microscope were adopted to study the precipitation behavior of non-metallic inclusions in Si steel slabs during reheating processes.The morphologies,chemical compositions,quantity and size distribution of non-metallic inclusions in these steel samples were analyzed.Results show that,when the soaking temperature is 1 523 K,almost all of the non-metallic inclusions are smaller than 0.5 μm,few are in the range of ...
无取向硅钢晶粒长大过程中应力对织构和晶界变化的影响
采用EBSD技术研究了有、无拉应力作用下无取向硅钢在晶粒长大过程中织构转变及晶界变化的规律。结果表明:在晶粒生长期间,无应力作用下的硅钢中,{111}〈112〉,{111}〈110〉织构组分强化,而{100}〈001〉织构组分弱化;与无拉应力作用下的情况相比,施加5MPa的拉应力时,{111}〈112〉,{111}〈110〉织构组分强化的速率下降,{100}〈001〉织构组分变化不明显。对于在晶粒生长期间持续变化的{111}〈112〉,{111}〈110〉和{100}〈001〉织构组分而言,虽然有、无拉应力作用下硅钢的{111}〈112〉和{111}〈110〉织构组分的高取向差角度晶界频率均下降,而{100}〈001〉织构组分的高取向差角度晶界频率则上升,但当有拉应力作用后,{111}〈112〉和{111}〈110〉织构组分的高取向差角度晶界频率下降的速率变小,{100}〈001〉织构组分的高取向差角度晶界频率上升的速率稍有变小。通过对无取向硅钢在晶粒长大过程中织构转变及晶界变化规律的研究,分析了合金原子在晶界的偏聚行为。 The rules of texture and grain boundary transformation in the nonoriented silicon steel under applied stress or without applied stress during grain growth were investigated by EBSD.The results show that the {111}〈112〉 and {111}〈110〉 components in the nonoriented silicon steel without stress are strengthened during grain growth whereas {100}〈001〉 component is weakened,but the growth rate of {111}〈112〉 and {111}〈110〉 component decreases,while the area fraction of {100}〈001〉 component doesn’t chang...
取向硅钢用特种氧化镁的应用研究
采用XRD、SEM和激光粒度仪等手段,观察并研究了不同特性氧化镁在硅钢表面形成硅酸镁底层形貌特点,并结合热力学和差热-失重分析了MgO-SiO2的反应机理。研究结果表明:粒度小,活性值高的特种氧化镁在高温退火过程中与基体表面氧化物生成的硅酸镁底层,界面中硅酸镁底层嵌入基体较多,表面致密,颗粒细小,有利于形成附着性能优良的硅酸镁底层。 Surface microstructure of Mg2SiO4 coatings formed on the surface of oriented silicon steel coated with different kinds of MgO was investigated by XRD and SEM.The reaction mechanism between MgO and SiO2 was analyzed by TG-DSC and thermodynamic calculation.Results revealed that when the MgO with finer microstructure size and higher activity is employed,a dense Mg2SiO4 layer with finer microstructure and good binding to the steel substrate can be obtained.The results are very helpful for the prepar...
承钢无取向电工钢CGW800的研发
承钢采用铁水预处理(脱硫)→转炉提钒→转炉冶炼→RH精炼→连铸→轧制工艺,成功研发了无取向电工钢CGW800。试制的CGW800钢碳含量≤0.006 0%、氮含量<0.004 0%,热轧后的金相组织为铁素体和少量渗碳体,晶粒度5.5级,获得了较粗大、均匀的晶粒,钢板的成分和力学性能达到了标准要求。 In Cheng Steel,the CGW800 non- oriented electrical steel is successfully developed with process of hot metal pre- treating,vanadium extracting with converter,smelting with converter,RH refining,continuous casting and rolling. In the steel,the carbon content is not higher than 0. 006 0%,nitrogen less than0. 004 0%,the metallographic structure after hot rolling is ferrite and a little amount of cementite,grain size is 5. 5 degree,relative large and even grain got. The composition and mechanical pr...
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...
温度及扩散时间对CVD法制备高硅钢的影响
采用CVD法制备6.5%Si高硅钢,介绍了具体的制备工艺过程,研究了温度对渗硅速率和试样质量减轻的影响,同时分析了扩散时间对高硅钢中硅分布的影响。结果表明:在CVD反应过程中,反应温度高于1050℃将大大提高渗硅速率,但当温度大于1200℃后,渗硅速率趋于稳定;渗硅后,试样会减轻、减薄,随着温度升高,试样质量减轻的速率逐渐增大,在1200℃左右趋于稳定;扩散时间越长,硅分布越均匀,结合制备效率进行考虑,满足Δw表-中/b≤5的时间为适宜的扩散时间。 6.5%Si high silicon steel was manufactured by using CVD method and the process was introduced,the influence of temperature on the siliconizing rate and quality reducing rate,diffusion time on silicon distribution were investigated.Results as follows: the siliconizing rate will increase quickly when the temperature is higher than 1050 ℃,but the siliconizing rate will become steadily as the temperature up to 1200 ℃;The quality reducing rate will increase with the elevating of temperature and the r...
含铜无取向电工钢中析出相及其析出机理
研究了含铜低碳低硅无取向电工钢中的析出相及其析出机理.由能谱(EDS)及选区电子衍射(SAED)分析可知,铁素体基体上存在的大量弥散分布的等轴状析出相为类B2结构的铜.这些铜析出相的析出机理可以是一般析出、位错析出、台阶机理相间析出和弓出机理相间析出:一般析出在550、650和750℃三个等温温度均可发生;位错析出只发生在较低的等温温度(550℃),此时析出相呈特殊的平行短列状;台阶机理相间析出也可在上述三个等温温度下发生,但650℃等温时最有利于台阶机理相间析出,此时析出相平直列状分布;弓出机理相间析出只发生在较高的等温温度(750℃),析出相弯曲列状分布. Precipitates in low-carbon low-silicon non-oriented electrical steel containing Cu were studied and the precipitation mechanism was analyzed by means of energy dispersive spectrometry(EDS) and selected area electron diffraction(SAED).It is found that the equiaxed precipitates of Cu with B2-like structure distribute dispersively in the non-oriented electrical steel.The precipitation mechanism involves general precipitation,dislocation precipitation,interphase precipitations formed by the ledge me...

