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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... 
2014-06-28 150 5.8

采用双辊薄带连铸工艺试制了2.6 mm厚5.28%Si-1.11%Al高硅钢薄带,对比了1050℃×5 min正火及不正火铸带280℃冷轧至0.5 mm后,再经900~1100℃退火的磁性能。结果表明,高硅钢铸带显微组织为等轴晶组织,正火后铸带边部晶粒长大,中心层晶粒变化较小。成品中析出物主要为较粗大的AlN和AlN+MnS复合析出物,尺寸为0.5~2.5μm。与不正火试样相比,正火试样成品铁损大幅降低,磁感小幅下降;随退火温度的升高,两种工艺下铁损和磁感都是先降低后升高,在1050℃出现最低值。 2.6 mm thickness 5.28% Si-1.11% Al non-oriented high silicon steel was produced by twin roll thin strip casting.Magnetic property of the strip un-normalized and normalized at 1050 ℃×5 min was contrasted after cold rolled to 0.5 mm at 280 ℃ and 900-1100 ℃ final annealing.The results show that microstructure of the strip is equiaxed crystal.The surface grain is coarsened and the center layer grain has little change of the normalized strip.The main precipitates are AlN and MnS+AlN with 0.5-2.5 μm s... 
2013-06-28 150 5.8

采用EBSD检测技术,分析了50W800无取向电工钢在重要生产工序间织构的演变以及织构沿带钢宽度方向上的差异性。结果表明:热轧板织构沿带钢宽度方向上的差异性主要体现在表层织构。带钢边部表层织构主要由旋转立方织构、α纤维织构以及少量的γ纤维织构组成,带钢宽度1/4处的表层织构主要存在高斯织构,带钢宽度1/2处的表层织构主要为(110)面织构以及少量的铜型织构。各处的带钢宽度1/4处和1/2处的织构类型基本一致,都以α纤维织构和旋转立方织构为主。冷轧后,各处的表层织构类型差异较小,均为γ纤维织构和α纤维织构。由板宽边部至中心处织构强度值逐渐降低。退火后,各处织构的组分基本一致,为较强的γ纤维织构和较弱的(100)面织构。各处织构强度值差异较小,变化趋势与冷轧板一致。 The texture of non-oriented electrical steel 50W800 was detected by EBSD technique.The evolution of the texture between important processes and the difference of texture along the width direction of strip were analyzed.The result shows that the difference along the width direction of strip of texture at the surface of hot rolled plate is most obvious.The texture at the surface of strip edge is primarily made of rotating cube texture,αfiber texture and weakγfiber texture.Goss texture is mainly co... 
2014-09-28 150 5.8

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 ... 
2011-09-28 149 5.8

【摘要】 <正>3月15日,随着第5754卷HiB钢下线,武钢...
2011-02-28 149 5.8

【作者】 安斌; ...
2014-09-28 149 5.8

利用场发射电镜及能谱仪研究了取向电工钢薄、厚板坯铸锭中不同区域的析出相差异,确定了MnS、AlN及Fe3C的析出顺序和形貌特征。结果表明AlN以先析出的MnS为形核核心,形成粗大微米级的复合析出相。针状Fe3C既可以在复合析出相表面形成也可以在基体中单独出现,主要受冷却速度的影响。在1250℃保温1~2 h,AlN、Fe3C均可完全回溶,但部分MnS仍不回溶。MnS尺寸随着保温时间延长而增大。导致热轧板中沿轧向分布的粗大MnS,减弱了粒子钉扎力。 Precipitates in thin and thick slabs of electrical silicon steel were investigated by means of field emission SEM and EDS analysis.The precipitation sequence and the morphology of MnS,AlN and Fe3C particles were identified.AlN particles are observed to be nucleated on surface of MnS forming micron-meter-sized complex particles.Acicular Fe3C can precipitate on surface of the complex MnS/AlN particles or directly from matrix depending on cooling rate of the slabs.After holding at 1250 ℃ for 1-2 h,... 
2011-08-28 149 5.8

硅钢工业退火炉温度控制具有强耦合、纯滞后、多扰动等特点,它的控制方法代表着一类非线性系统控制的解决方法。以硅钢工业退火炉温度为控制对象,在双交叉限幅控制的基础上引入了智能学习系统,形成了基于智能学习系统的双交叉限幅控制方法来解决此类非线性系统的控制问题,并通过模块化的编程来实现其功能。结果表明:与传统的PID控制相比,该控制方法的控制精度、抗扰性等控制指标有明显提高,是解决此类非线性控制的一种有效方法。 The temperature control of silicon steel industrial annealing furnace has the features of strong coupling,pure lag,multidisturbance. The control method represents the solution of a class of nonlinear control systems. The control object is the temperature control of silicon steel industrial an-nealing furnace, the intelligent learning system based on Double Across Limit Control is introducedand used to solve control problem of this kind of nonlinear system, and the module programming isused to re... 
2014-05-28 149 5.8

借助于EBSD对比研究了常化退火对高牌号无取向电工钢热轧组织和织构演变的影响,分析了常化退火对热轧板各厚度层织构的演变规律。结果表明,常化退火改善了热轧组织的均匀性,并弱化了热轧变形的γ纤维织构。升高常化退火温度,可增大热轧板的晶粒尺寸,提高{100}和{110}织构组分占有率,有利于提高无取向电工钢成品板的磁性能。 Effects of normalizing annealing on microstructure and texture of high-grade non-oriented electrical steel hot-rolled sheet were investigated by EBSD. Emphasis was put on the effects of normalizing annealing on texture evolution in the sheet thickness. The results show that the hot-rolled microstructure homogeneity is improved and the γ-fiber texture is weakened by normalizing annealing treatment. The grain size of hot-rolled sheet and intensity of the {100} and {110} favorable texture can be in... 
2014-02-28 149 5.8

在15 kg真空感应炉上,用CaO-Al2O3-SiO2-MgO渣系进行脱硫试验,探讨了脱硫渣系碱度、MI、Al2O3、CaF2对脱硫效果的影响。研究结果表明,随脱硫渣系碱度、MI、Al2O3和CaF2含量的增加,脱硫率都呈现先增加后减少的趋势。初始硫含量为0.009 33%~0.010 73%,加入脱硫渣系4 min时间内表观脱硫速率为(0.000 96~0.001 49)%/min,平均脱硫率为81.2%,最高达86.8%。当脱硫渣中w(CaO)=58.15%、w(SiO2)=4.85%、w(Al2O3)=25%、w(MgO)=6%、w(CaF2)=6%,脱硫效果最好,此时钢液中硫为0.001 33%。 Experiments on desulfurization of molten steel using CaO-Al2O3-SiO2-MgO based desulfurization slag was carried out in a 15 kg vacuum induction furnace. The effects of desulfurization slag basicity,MI, Al2O3and CaF2on desulfurization of molten steel were studied. The results show that with the increase of basicity,MI,Al2O3or CaF2in desulfurization slag,the desulfurization rate rises initially and then decreases. In addition,as the initial sulfur content is 0. 009 33% ~ 0. 010 73%,the apparent des... 
2014-02-28 149 5.8

利用DSC、XRD,结合热焓分析对硅钢级氧化镁和二氧化硅的固相反应行为进行了研究。比较了不同二氧化硅原料及混合方法对硅钢级氧化镁反应性的影响,找到了一种更为有效的硅钢级氧化镁反应性的评估方法,克服了传统柠檬酸活性法在比较不同厂家生产的氧化镁的反应性上的局限性。进一步研究了Na2B4O7添加剂、TiO2添加剂对氧化镁和二氧化硅反应行为的影响,结果表明,Na2B4O7添加剂含量的增加对反应有利,而TiO2添加剂对反应有阻碍作用。 The solid-state reaction behavior between silicon-steel grade MgO and SiO2 was investigated by DSC and XRD combined with enthalpimetric analysis.The influence of different kinds of SiO2 and different preparation methods were studied and a specifical measurement that is more reliable was proposed to evaluate reactivity of silicon steel grade MgO.It overcomes the limitation of the traditional citric acid activity(CAA) method,which can not be used to evaluate the reactivity of... 
2014-03-28 149 5.8

为提高无取向硅钢导磁性能,研究了不同剪切方式对无取向硅钢剪切处磁畴结构的影响。利用纳米磁流体观测无取向硅钢剪切后边部磁畴结构。结果表明,硅钢无论在机械剪切还是线切割后的边部磁畴都会发生不同程度的改变:线切割对边部磁畴结构改变较小,边部磁畴分布均匀且连续,在距边缘0~20μm范围内出现磁畴宽度变小现象;机械剪切对磁畴的改变较为严重,剪切处磁畴零乱且不连续,在距边缘20μm处仍难以观察到完整的磁畴结构。 The effects of different shearing modes on magnetic domain structure of cold rolled non-oriented silicon steel are studied in this paper.The magnetic domain of cold rolled non-oriented silicon steel is observed by nanometer magnetic fluid pattern method.The results show that the edge magnetic domain structure will be changed by mechanical shear and wire-electrode cutting,the variation of edge magnetic domain structure wire-electrode cutting edge is very small,the magnetic domain structure is wel... 
2012-04-28 149 5.8

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