钢厂
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...
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 ...
无取向硅钢铬酸镁绝缘涂层高温固化工艺
为了确保硅钢铬酸盐涂料的环保性,需要严格控制涂料的固化工艺,保证涂料固化过程中涂料中的六价铬充分转化为三价铬。对涂料及原料进行热重分析(TG)及差示扫描量热法分析(DSC)。结果表明,MgO与铬酐混合转化为MgCrO4,使六价铬稳定性增强,其中大部分Cr6+转变为Cr3+发生在620~700℃,在450~500℃高于铬酐发生大量失重,因此必须加入还原剂保证涂料中六价铬被充分还原;超过360℃后树脂会发生分解,因此实际板温不能超过360℃;加入了还原剂的整体涂料的失重温度区间主要在260~320℃,因此涂料固化时钢板的实际温度最佳区间为320~360℃。 Because of the silicon steel chromate coating’s environmental requirements,the paint curing process must be controlled strictly to ensure all Cr( Ⅵ) transforms to Cr( Ⅲ). The TG and DSC analyses of the paint are studied. The reaction of MgO and CrO3 would generate MgCrO4,enhancing the stability of Cr( Ⅵ). The most r( Ⅵ) in MgCrO4 changes to Cr( Ⅲ) at 620-700 ℃,while the CrO3 has a large weight loss at 450-500 ℃. The reductant must be added in the paint to make sure the Cr( Ⅵ) could transform suf...
冷轧电工钢森吉米尔轧机研究进展
森吉米尔二十辊轧机是冷轧电工钢的主要机型,具有整体刚度大,辊径小,轧制道次压下量大,产品精度高等特点,简要介绍了近年来冷轧电工钢森吉米尔二十辊轧机领域进展,在轧机结构、厚度自动控制、板形自动控制等方面的技术及研究。 20-h Sendzmir reversible mill is the main type of cold rolled electrical steel which has the characteristic of high integral stiffness,small roller diameter,high pass reduction and high product quality.In this paper,the recent progress of frame structure,automatic gauge control,automatic flatness control of Sendzmir mill is introduced.
热处理工艺对含Mn高硅钢热轧带的组织及硬度的影响
研究了热处理工艺(退火温度、保温时间、冷却方式)对含Mn的Fe-6.5wt%Si高硅钢热轧带的显微组织及硬度的影响。结果表明,退火温度对Fe-6.5wt%Si合金的组织和显微硬度均有较大影响,随退火温度升高,平均晶粒尺寸和显微硬度均明显增大。小于1 h退火时,晶粒长大缓慢,而长时间(>1 h)退火时,一些次表层晶粒将发生异常长大。水冷组织比空冷组织略细小,但水冷显著降低了显微硬度。Mn含量提高能抑制850℃退火时晶粒的长大,并且促进退火后高硅钢的软化。 The influences of heat treatment process(annealing temperature,heating time,cooling methods) on the microstructure and microhardness of Fe-6.5wt%Si high silicon steel containing manganese for hot rolled strip were studied.The results show that the annealing temperature has a great effect on the microstructure and microhardness of Fe-6.5wt%Si alloy,and as the annealing temperature increases,the average grain sizes and microhardness will significantly increase.When annealing time for less than 1 h...
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 ...
西昌钢钒200t RH生产无取向硅钢的工艺实践
对西昌钢钒炼钢厂200 t BOF(顶底复吹)-RH-CC工艺生产50PRW800无取向硅钢RH精炼过程中主要成份进行了分析。找出了目前工艺中影响钢液质量的主要因素是钢水脱氧处理不彻底,造成加入的部分硅元素烧损。操作工艺改为铝的脱氧即合金化操作一步完成,保证了钢水中氧处于一个较低的范围,从而减少对硅元素的烧损,提高合金收得率。 The factors of BOF-RH-CC process affecting the compositions of liquid steel were systematically investigated and studied of Xichang Steel and Vanadium Company. The main factors affecting the steel cleanliness were picked out. All results showed that the loss of silicon elements resulting from the deoxidization of liquid steel was not completely. It was suggested that the addition of aluminum for deoxidizing and alloying of molten steel was executed as one step in order to lower the oxygen potent...
RH精炼喂CaSi线去除无取向硅钢中的非金属夹杂物
结合工业化生产的无取向硅钢,进行了RH精炼喂CaSi线去除钢中的非金属夹杂物试验研究。针对不同的钙处理条件,分析了CaS夹杂生成热力学,观察了夹杂物的形貌和尺寸分布,确定了夹杂物的类型、数量,探讨了钙处理后钢中夹杂物的变化规律。结果表明,本试验条件下,钙处理可以有效抑制MnS、AlN夹杂物的生成,有效促进钢中微细夹杂物的聚合、上浮、去除,钢质纯净度明显提高。经过合适的钙处理后,钢中的夹杂物以独立存在的CaO为主,同时有少量含CaO、SiO2、MgO的复合夹杂,没有发现CaS夹杂存在。这部分夹杂物的尺寸集中分布在2～20μm,数量约为1.8×105个/mm3。 Experimental study on removal of non-metallic inclusions in non-oriented silicon steel obtained from industrial production by CaSi wire feeding during RH refining process was carried out.The thermodynamics of CaS inclusion formation was analyzed,the morphology and the size distribution of inclusions were observed,and the numbers and types of inclusions were also determined for the steel specimens treated under different calcium treatment conditions.Furthermore,the variation of inclusion characte...
