钢厂
硅钢常化炉段工艺特征及问题分析
连续酸洗退火机组(CPAL)对于当前生产高磁感取向硅钢和高牌号无取向硅钢是必不可少的一个环节。常化炉是常化酸洗机组关键的组成部分。本文对国内自主建造的两条退火酸洗机组的工艺流程,特别是常化炉段进行了对比分析。总结出了常化炉的工艺及组成特点,对生产过程中暴露的问题进行了仔细的分析并提出了改进的意见,对于以后新建常化炉具有一定的提示作用。 The continous pickling annealing line(CPAL) is an essential step in producing high magnetic induction grain-oriented silicon steel and high grade non-oriented silicon steel.The normalizing furnace is a very important part of the CAPL.In this paper,the process flows of two CAPL with independent manufacture in our country have been compared,especially the part of normalizing furnaces.The characteristics of process and component are summarized and problems of the normalizing furnace during the prod...
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 ...
硅钢CSP工程辊底式均热炉技术特点
介绍了硅钢CSP工程辊底式均热炉的技术特性,详细阐述了辊底式均热炉工艺特点。根据硅钢均热要求,通过采取不同烧嘴布置方法和燃烧控制技术,选用耐火纤维模块和绝热材料等相关技术措施,满足了出钢温度要求。 The technical specialty for roller hearth furnace of silicon steel CSP Plant was introduced,and the technology characteristics of the roller hearth furnace were illuminated in detail.According to the reheating require of the silicon steel,different burner arrangement and combustion control methods were applied,and technology measures such as selecting refractory fiber module and insulation material and so on were taken,the temperature requirement of silicon steel was met.
硅钢高温氧化铁皮的显微结构表征
利用电子探针面分析、状态分析及电子背散射衍射相分析技术研究硅钢高温氧化铁皮的显微结构。电子探针面分析可以直观的看出元素的分布状态,初步判断氧化铁皮的结构,而状态分析可以准确表征常规氧化铁皮中铁元素的状态,对于合金元素富集区域则通过电子背散射衍射相分析技术来标定。结果表明,高温氧化铁皮的结构主要有4层,即最外层为厚度约为10μm的Fe2O3相,次外层为Fe3O4相,中间层为FeO相上分布有颗粒状的Fe3O4相,最内层为FeO相和Si元素富集的Fe2SiO4相。其中Fe2SiO4层的分布特征与加热温度密切相关:1 100℃时,Fe2SiO4相呈颗粒状,弥散分布在FeO层;1 200℃时,Fe2SiO4相呈液态,侵入基体和疏松的FeO层,且沿着FeO晶界呈网状分布。 The microstructure of high temperature oxide scale on silicon steel was characterized by electron probe microanalyzer(EPMA)mapping analysis,state analysis and electron backscatter diffraction(EBSD)phase analysis.The element distribution and the initial structure of the oxide scale could be detected by EPMA mapping analysis apparently.And the state of iron in the conventional oxide scales could be determined by state analysis.Meanwhile,the alloy-rich region could be identified by EBSD phase analy...
卷取工艺对新型冷轧无取向电工钢热轧带组织的影响
利用OM、SEM、TEM等实验方法研究了卷取工艺对一种新型含铜无取向电工钢晶粒度和析出相的影响。结果表明,该电工钢热轧带卷取后的晶粒尺寸为18～24μm,在卷取过程中,热轧带中有一定数量的第二相析出,经EDS能谱及选区电子衍射分析,这些析出相主要为AlN。随着卷取工艺的变化,该电工钢的晶粒度大小变化不明显,析出相的类型、尺寸大小不发生改变,体积分数发生一定的改变。 The effects of coiling process on grain size and precipitates of a new copper-bearing non-oriented electrical steel were investigated by OM,TEM and other experimental method.The results show that the grain size of hot-rolled bands after coiling is 18～24 μm.The second phases precipitate during coiling process.They are mainly AlN by EDS spectra and selected area electron diffraction.With the change of coiling process,the grain size of the electrical steel does not change significantly;the type and...
低温取向硅钢热轧态组织及织构的研究
利用热模拟试验机、光学显微镜和X射线衍射仪对Fe-3.2%Si低温取向硅钢热轧工艺参数对组织及织构的影响进行了研究。结果表明,Fe-3.2%Si硅钢在1110℃粗轧、880℃终轧,轧后以10℃/s的速度冷却到550℃卷取,然后空冷到室温,热轧硅钢板沿板厚方向的显微组织不均匀性显著,对后续发展完善的二次再结晶有重要作用。无论是热轧板,常化板还是冷轧板,它们的织构集中分布在γ取向线上,γ取向线的织构除取向密度不同外,织构种类是一致的,这说明γ取向线上织构是有继承性的。从热轧到常化,织构取向密度显著减小,经二次冷轧后,织构密度又显著升高,可见,轧制变形有助于织构的形成并使织构强度升高。 The influence of hot-rolled process parameters on the microstructure and texture of Fe-3.2%Si low temperature hot rolled grain-oriented silicon steel were researched by hot simulation experiment machine,light microscope and X-ray diffractometer.The results show that,Fe-3.2%Si silicon steel is rolled by the technology with a temperature of rough rolling of1110℃,finish rolling of 880℃,coiling with the speed of 10℃ /s,and then cooled to room temperature with air.The microstructure of hot-rolled sil...
低牌号无取向电工钢磁时效行为分析
选取了三种50W 800无取向电工钢,分析了化学成分、晶粒尺寸、织构、以及200℃时效处理48 h前后的磁性能和第二相粒子析出状态的变化。结果表明,钢板中第二相粒子的分布密度对钢板铁损有最重要的影响。降低钢中C、N元素含量,或改进钢板热加工参数以降低成品钢板中第二相粒子形成元素的过饱和度均有利于明显降低钢板磁时效过程中的铁损增幅。钢板中对磁性能有利的织构也有利于降低钢板铁损的时效幅度。 The evolution of chemical composition,grain size,texture,as well as magnetic property after aging treatment at 200 ℃ for 48 h and distribution of second phase particles precipitation in three selected 50W800 non-oriented electrical steels were analyzed.The results show that the distribution density of second phase particles has great influence on core loss.Reducing C and N content,or improving hot-working parameters to reduce the supersaturation of elements forming second phase particles in prod...
无取向硅钢中的夹杂物析出在线观察
借助高温激光共聚焦显微镜,在线观察了不同Mn含量的无取向硅钢中夹杂物的尺寸、类型、数量变化。结果表明,Mn含量(质量分数)为0.77%、0.32%时,试样中的夹杂物数量分别约为1000万个/mm3、1600万个/mm3。Mn含量较高的钢种,会优先析出球形、椭球形MnS夹杂物,其析出数量较少,尺寸相对较大,可以有效抑制AlN、CuxS夹杂物析出;Mn含量较低的钢种,会在试样再加热后冷却过程中,先析出相当数量MnS夹杂物,并作为AlN夹杂物析出核心,形成MnS+AlN复合夹杂物。这种复合夹杂物数量较多,尺寸也较大。 Based on the high temperature confocal microscope, the chage of size, type, and quantity of inclusions in non-oriented silicon steels with different Mn content were observed by in-situ SEM. Results show that the inclusion quantities are 10 million per mm3 and 16 million per mm3,while the mass fractions of Mn are 0.77% and 0.32%, respectively. In the silicon steel with higher Mn content, the spherical and ellipsoidal MnS inclusion will precipitate first, which can retard the precipitation of AlN ...
