钢厂
电工钢中柱状晶对热轧和退火时晶粒取向及组织的影响
利用EBSD技术研究了电工钢中长轴平行于轧向的柱状晶样品在热轧和退火过程中组织和取向的演变规律,并与长轴平行于板法向的样品的已有研究结果进行对比。结果表明,无论柱状晶按何种方向排列,只要表面存在剪切力,热轧后都可形成剪切织构,同时中心形成轧制织构,主要包括旋转立方织构和{112}<1-10>。柱状晶造成的影响主要体现在板中心层,长轴平行于轧向排列的样品热轧时形成的粗大旋转立方晶粒要到脱碳退火后才能完全消除,但破坏了正常的不同取向晶粒间的取向差分布及尺寸均匀性,导致二次再结晶不完全及磁性能降低。 The evolution of microstructure and grain orientation in an electrical steel containing columnar grains with its long axis being parallel to the rolling direction of sheet was studied during hot rolling and annealing by EBSD technique.The results are compared with those of samples containing columnar grains being parallel to normal direction of sheet reported in the reference [3].It was shown that,whether the long axis of columnar grains was arranged in RD or ND,shear textures can be formed in t...
常化温度对TSCR流程制备低碳低硅无取向硅钢组织和性能的影响
在实验室试制了TSCR流程的低碳低硅无取向硅钢,研究了在850～1050℃不同温度常化对冷轧量0.5mm厚钢板再经950℃×7min退火后的组织、织构和磁性能的影响。结果表明:随常化温度的升高,使热轧板晶粒尺寸增大,晶界更清晰,组织均匀性更好;由于第二相AlN和MnS析出物尺寸比较大,使冷轧退火后钢板晶粒也随常化温度升高呈单调增大趋势;γ有利织构和{111}、{112}不利织构与常化温度升高同时增强,但前者增强更多;冷轧板退火后铁损随常化温度升高呈单调下降,磁感呈单调上升趋势。 The low-carbon and low-silicon non-oriented silicon steel was prepared by thin slab casting and rolling(TSCR) in lab.The effect of normalizing at different temperatures in 850-1 050℃on microstructure, texture and magnetic properties of 0.5 mm cold-rolled sheets after annealing at 950℃for 7 min was researched. The results show that with increasing the normalizing temperature,the grain size of hot-rolled sheets increased,the grain boundaries were more clear and the rnicrostructure uniformity was b...
轧制裂纹及热处理工艺对高硅电工钢复合板磁性能的影响
对3层高硅电工钢复合板铸坯进行热轧及温轧变形加工后，采用正火、退火两种热处理方式处理，并观察轧制过程中产生的裂纹，研究不同状态下复合板的磁性能。对不同状态下的试样进行扩散退火处理，研究复合板中裂纹变化及其对磁性能的影响。结果表明：不同热处理工艺下合金内部的裂纹尺寸差异明显，裂纹尺寸对复合板的磁性能影响显著，相对于深裂纹，其他因素的影响较小；温轧变形加工后，复合板内层出现有序组织，但该有序组织在合金存在深裂纹的前提下并不能从本质上提高合金的磁性能；扩散退火工艺可以消除复合板内部的浅裂纹及微裂纹，但不能消除尺寸较大的裂纹，故而不能显著提高存在深裂纹的复合板的磁性能。 After hot rolling and warm rolling deformation processing of casting billet for three-layer high silicon electrical steel composite plate, it was normalized and annealed for heat treatment. Then, the cracks produced during the rolling process were observed, and the magnetic properties of composite plate in different states were also investigated. Furthermore, the samples in different states were subjected to diffusion annealing treatment, and the changes of crack in composite plate and their eff...
无取向硅钢热轧边裂的形成原因
利用加热炉模拟、动态再结晶以及热模拟等试验方法以及扫描电镜、金相显微镜等分析观察手段对无取向硅钢边裂的成因进行了探讨。结果表明,长时间加热使得板坯边部晶粒异常长大,晶界氧化并脱碳,轧制过程中边部温度过低,动态再结晶过程变弱,使得板坯边部延伸性能变差,是导致硅钢边裂的主要原因。建议通过适当降低铸坯加热温度、缩短保温时间、提高终轧温度来改善硅钢边裂缺陷。 The behaviors of high temperature oxidation,dynamic recrystallization,and hot ductility,microstructure evolution were investigated on the non-oriented electrical steel sheets to discuss the formation of edge crack.The key causes of cracking was found to be the coarse as-cast microstructure,grain boundary oxidation and decarburization in reheating furnace,as well as reduced temperature at strip edge region during hot rolling process resulting in reduced hot ductility and lack of enough dynamic re...
低硅钢冶炼过程硅质量分数控制
抑制回硅是低硅品种钢冶炼的重点和难点,南钢中厚板卷厂通过转炉出钢弱脱氧操作,精炼炉弱脱氧升温,脱氧、脱硫造渣,连铸严格的保护浇注及吹氩塞棒、吹氩浸入式上水口的应用等一系列工艺优化和操作的改进,使整个冶炼过程钢水回硅量稳定控制在200×10-6以内,钢水终点成分完全满足低硅钢要求。 Control of increasing silicon is the emphasis and difficulty in low silicon varieties steel smelting.The Nisco Wide Plate/Coil Plant can control the silicon content in molten steel keeping within 200×10-6 through whole steelmaking process by using oxygen residual operation in converter tapping,oxygen residual and increasing temperature,deoxidation,desulfurization,slag refining,protection cast,blowing argon by plugged nozzle,blowing argon by submerged entry nozzle in continuous casting,and other ...
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...
常化退火处理对无取向硅钢组织和织构的影响
采用光学显微镜和X射线衍射仪研究了常化退火处理对无取向硅钢热轧板和成品退火板显微组织和织构的影响。结果表明:常化退火处理消除了热轧板中的变形组织,促使变形晶粒完成再结晶;常化退火处理使高斯织构和立方织构易通过再结晶在变形带内形核和长大,可显著降低成品退火板的{111}和{112}不利织构组分的占有率,提高{100}和{110}有利织构组分的占有率,从而有利于提高无取向硅钢成品板的磁性能。 The effect of normalizing annealing treatment on microstructure and texture of non-oriented silicon steel hot rolled plates and final products were investigated by means of optical microscope and X-ray diffractometer analysis.The results show that the deformed microstructure of the hot rolled plates transformed into recrystallized grain after normalizing annealing treatment.The grains of Goss texture and cubic texture crystallographic orientation were formed and grown by recrystallization in the...
退火温度对双辊连铸无取向硅钢组织的影响
利用光学显微镜、TEM和EBSD研究了退火温度对双辊连铸无取向硅钢再结晶组织的影响。结果表明,900℃退火后组织分布不均匀,有大量带状组织,平均晶粒尺寸29.5μm。提高退火温度,晶粒尺寸增大,组织均匀化程度增加,1050℃退火时,带状组织基本消失,平均晶粒尺寸42.2μm。 Effect of annealing temperature on recrystallization microstructure of non-oriented electrical steel produced by twin-roll casting process was investigated using OM,TEM and EBSD.The results show that the recrystallization microstructure is uneven because of many banded grains existing,average grain size is 29.5 μm.With annealing temperature increasing,the recrystallization grain size increases,microstructure becomes more homogeneous.When 1050 ℃ annealing,the banded structure almost disappear and...
