钢水氧含量的预报与控制

通过测量湘钢炼钢厂80吨转炉终点钢水氧含量,回归得出转炉终点钢水氧含量主要取决于终点碳含量、钢水温度、终点锰含量和终渣氧化性,由此得出脱氧合金化时,脱氧量方程与脱氧剂加入量。     

Influence of Conductivity of Slag on Decarburization Reaction

By altering the electrochemical properties of slag, the decarburization reaction of Fe3+-based slag withFe-C droplet was studied. The results showed that a lot of free electrons and holes exist in the slag containing transition metal oxides (such as TiO2 and Fe2O3). So electronic conduction in the slag increases. Finally, it led to the increment of the decarburization reaction rate between slag and Fe-C droplet, and mass fraction of carbon remaining indroplet decreases to a lower level.     

转炉炼钢渣中Cu_2O与NiO的还原实验研究

结合某钢厂顶底复吹转炉冶炼含有铜、镍等成分耐候钢的生产过程,在实验室对铁碳熔体和纯铁液还原炼钢渣中铜、镍等氧化物进行研究。结果表明,在初始条件相同的情况下,1 300℃下铁碳熔体分别还原渣中Cu2O和NiO时,Cu2O比NiO更易还原,还原速度更快。1 600℃时在实验研究的碱度范围内,含有25%FeO的转炉终点渣中Cu2O、NiO能被纯铁液在10~20 min内还原完毕,尤其前10 min内w[Cu]、w[Ni]增长迅速。在相同碱度下,渣中Cu2O、NiO同时还原的速率基本相同;随着渣碱度的增大,Cu2O、NiO还原的速率及终还原率均有所降低。     

转炉溅渣护炉炉渣物性研究

针对转炉后吹和正常吹炼终渣FeO变化较大的特点 ,对炉渣的成分、熔化性温度和岩相结构进行研究 .研究结果为转炉溅渣护炉终渣成分的调整提供了一些依据     

冶金炉渣电子理论的研究

在宏观冶金热力学的基础上,将具有微观电子化学势内涵的氧分压引入冶金工艺原理中,进行了冶金炉渣电子理论的研究,得出炉渣组元i的活度计算公式及冶金过程中铁液内的元素i氧化还原的热力学判据——氧化还原势。     

LD-BAr-CC工艺生产低碳铝镇静钢纯净度研究

研究武汉钢铁股份有限公司炼钢总厂四分厂LD-BAr-CC工艺条件下生产的低碳铝镇静钢的纯净度,分析各工艺阶段钢中显微夹杂、大型夹杂以及全氧、氮含量的变化情况。结果表明,在该厂现行工艺条件下,采用吹氩工艺可明显降低钢中夹杂物含量和全氧含量,全氧含量从精炼前的109.30×10-6降至30.75×10-6。各工序中钢的显微夹杂物主要为Al2O3和SiO2,这是脱氧产物和钢液二次氧化产物在钢中的残留物;大型夹杂物主要是Al2O3、SiO2以及硅铝酸盐等复合夹杂,与浮渣的卷入有很大关系。     

马钢电弧炉弹簧钢60 Si2 MnA氧含量技术可行性研究

针对马钢100t电弧炉EAF→LF→RH生产弹簧钢60Si2Mn A的冶炼生产工艺流程,采取系统的取样、综合分析弹簧钢冶炼过程中全氧变化规律及影响因素,结果表明:在电弧炉-LF精炼-RH真空处理中,全氧含量基本是逐渐降低的;通过精炼全程底吹氩气,采用顶渣操作和高碱度(R=3.5)精炼渣,来降低渣中氧化物的含量及活度,均有利于降低弹簧钢中的全氧含量;钢水中氧含量最终可以控制在10ppm以内;     

Photogenerated carrier transfer mechanism and photocatalysis properties of TiO2 sensitized by Zn（ Ⅱ ） phthalocyanine

The Zn(Ⅱ) phthalocyanine sensitized TiO2(ZnPc-TiO2) nanoparticles were prepared by hydrothermal method via impregnation with ZnPc.The as-prepared photocatalysts were characterized by X-ray diffractometry(XRD) and diffuse reflectance spectroscopy(DRS),and the surface photovoltage spectroscopy(SPS) and photocatalytic degradation of rhodamine B(RhB) were studied under illuminating.The experimental results indicate that TiO2 sensitized by ZnPc extends its absorption band into the visible region effectively,and ...     

Theoretical calculation and experimental study of influence of oxygen vacancy on the electronic structure and hemocompatibility of rutile TiO2

In this work, the relationship between electronic structure and hemocompatibility of oxygen deficient rutile TiO_2?x was studied by both theoretical calculation and experimental study. Based on the local density functional theory, first-principals method was performed to calculate the electronic structure of rutile TiO₂ with different oxygen vacancy concentration. In the range of less than 10% of (or equal) physically realistic O vacancy concentration, the band gap of rutile TiO₂ increases with increasing O vacancy concentration, leading the TiO₂ changes from a p-type to an n-type semiconductor. The valance band of TiO₂ is predominated by O 2p orbital, while the conduction band is occupied by Ti 3d orbital for different O vacancy concentration. The O vacancy results in the occupation of electrons at the bottom of conduction band of TiO₂, and the donor density increases with increasing O vacancy concentration. When materials come in contact with blood, the n-type semiconductor feature of oxygen deficient TiO_2?x with the bottom of conduction band occupied by electrons would prevent charge transfer from fibrinogen into the surface of materials, thus inhibiting the aggregation and activation of platelets, therefore improving the hemocompatibility of rutile TiO_2-x .

     

钢液脱铜的渣系研究

开发一种FeS基的脱铜渣,能有效进行钢水脱铜,脱铜率可高达71．6％。实验结果表明用FeS渣系进行钢水脱铜时,脱铜率随钢水原始铜含量和渣中FeS含量的增加而增加;钢水中碳含量对脱铜影响较大,碳含量越高脱铜率越高;温度影响FeS渣系钢水脱铜的效率,温度越高脱铜率越低。     

熔钢与Na2O-Li2O-SiO2-B2O3熔渣间的界面作用研究

通过测定1803～1873K温度范围内3种熔钢与Na2O-Li2O-SiO2～B2O3熔渣间的界面张力值，研究了其间的相互作用。结果表明，在此温度范围内，随着熔钢中氧、硫含量的增加，界面张力值大幅降低，渣金间的相互作用加强，界面张力值随着渣中SiO。含量的增加而减小，随着Na2O和Li2O含量的增加而增加。     

Theoretical calculation and experimental study of influence of oxygen vacancy on the electronic structure and hemocompatibility of rutile TiO2

In this work, the relationship between electronic structure and hemocompatibility of oxygen deficient rutile TiO_2−x was studied by both theoretical calculation and experimental study. Based on the local density functional theory, first-principals method was performed to calculate the electronic structure of rutile TiO₂ with different oxygen vacancy concentration. In the range of less than 10% of (or equal) physically realistic O vacancy concentration, the band gap of rutile TiO₂ increases with increasing O vacancy concentration, leading the TiO₂ changes from a p-type to an n-type semiconductor. The valance band of TiO₂ is predominated by O 2p orbital, while the conduction band is occupied by Ti 3d orbital for different O vacancy concentration. The O vacancy results in the occupation of electrons at the bottom of conduction band of TiO₂, and the donor density increases with increasing O vacancy concentration. When materials come in contact with blood, the n-type semiconductor feature of oxygen deficient TiO_2−x with the bottom of conduction band occupied by electrons would prevent charge transfer from fibrinogen into the surface of materials, thus inhibiting the aggregation and activation of platelets, therefore improving the hemocompatibility of rutile TiO_2-x . Supported by the National Basic Research Program of China (Grant No. 2005CB623904), National High-Tech Research Program of China (Grant No. 2006AA02A139) and National Natural Science Foundation of China (Grant No. 20603027)     

Optimum Slag Basicity for Deoxidation DuringSecondary Refining Process

According to the coexistence theory of slag structures, the calculating model of the oxidizing capabilityfor CaO-MgO-FeO-Al2O3-SiO2 refining slag system has been deduced. Based on this model, the concept and thecalculating method of the optimum slag basicity are put forward. The results have proved that at this basicity,steel with lower oxygen content can be obtained and non-metallic indigenous globular inclusions can be avoidedmore effectively than at other basicity.     

密闭直流电弧炉钛渣生产还原剂碳因素分析

密闭直流电弧炉冶炼钛渣所用原料主要为钛铁矿和无烟煤,利用无烟煤中的碳高温冶炼还原.钛渣冶炼过程中,控制直流电弧炉入炉物料中无烟煤用量与钛铁矿用量的比例,使生产过程在密闭直流电孤炉输入功率保持一定、钛铁矿成分相对稳定的条件下,以获得良好的钛渣产品品质.无烟煤比例过大,产品钛渣中TiO2的含量下降,同时会增大熔渣的还原度,渣中低价氧化物的量增多,导致熔渣黏度和电耗增加.如果无烟煤比例偏小,达不到需要的还原度,碳最大可能的消耗在FeO的还原上,直接影响产品品质.当无烟煤比例达到一定程度,继续提高该比例,抑制了FeO的还原反应,杂质还原后富集进入渣相,使钛渣中TiO2受到稀释而贫化,不能提高钛渣的品位.在功率一定的条件下,入炉物料中无烟煤比例成为影响钛渣品位高低的关键因素.以云南某密闭直流电弧炉熔炼周期的生产数据得到其冶炼中无烟煤配碳比为12.403％.     

Application of Al-free deoxidizer in rail steel manufacture

Because there are a lot of influences of alumina inclusions on the performance of rail steel, it is reasonable to adopt the deoxidizatinn method with Al-free deoxidizer. According to the characteristics of Al-free deoxidization process, the control of alu-minum content, the denxidization with ladle furnace(LF) slag, the deoxidization process under vacuum by carbon, and the inclusions modification technology by calcium treatment were studied. All of them were applied to practical production. The results indicate that the adoption of Al-free deoxidization process leads to the total oxygen content in the steel below 20 ppm, which meets the re-quirement of clean rail steel.     

莱钢120吨转炉冶炼超低硫钢工艺优化

结合脱硫反应热力学和动力学理论,对莱钢120t转炉冶炼过程及操作制度进行了分析研究,通过控制转炉回硫对深脱硫工艺流程进行了优化。结果表明:(1)通过控制转炉回硫,可将LF炉中钢水硫质量分数控制在0.005%以下,脱硫率可达80%以上,终点硫质量分数最低可达到0.001%,并且能够稳定生产硫质量分数小于0.005%的低硫钢种;(2)顶渣SiO2质量分数可控制在8%以下;(3)终点(FeO+MnO)质量分数和可降低到1%左右,碱度可控制在5～6之间。     

添加锰粉对铝碳耐火材料抗侵蚀性的影响

石墨和结合碳的氧化是铝碳耐火材料在使用中损坏的重要原因之一．研究了锰粉在铝碳耐火材料中抗渣蚀性的作用，与仅添加Si或Al的试样相比，添加Mn的试样抗侵蚀性较低，复合添加Si和Mn的试样的抗侵蚀性均有提高．     

自蔓延高温反应合成NiCuZn铁氧体粉料的研究

以碳粉作为SHS反应的燃料合成(Ni0.2Cu0.2Zn0.6O)1.02(Fe2O3)0.98铁氧体粉料,通过XRD、SEM和VSM等检测手段,研究了C粉含量和氧气压力对NiCuZn铁氧体烧结样品的物相、形貌及磁性能的关系.研究表明,当氧气压力为0.2 MPa时,C质量分数为5%时,可获得铁氧体化较完全的铁氧体料粉,其饱和磁化强度为45.5 Am2/kg;随着C含量增加,产物中有ZnO相的出现,饱和磁化强度降低.当C质量分数为15%时,随着氧气压力的增大,铁氧体尖晶石相的衍射峰逐渐变锐,晶形转变趋于完整.     

含钛渣短流程直接制备钛及其合金

利用固体透氧膜（SOM ）法直接由含钛渣还原制备金属钛及其合金。将粉态含钛渣压片制成阴极,以YSZ管内碳粉饱和的铜液为阳极,以1100℃电解温度、3．5 V槽电压在CaCl2熔盐中电解,研究成型压力及电解时间对电解产物的影响,分析电解过程中的杂质行为。结果表明,随电解时间的延长,电解产物中的钛、铁含量不断增大,产物颗粒形貌趋于匀细疏松;对于铁钛渣,电解6h可获得钛铁合金;对于高钛渣,成型压力为3MPa时,电解4h可除去氧,电解6h可获得纯金属钛;较小成型压力下的多孔阴极有利于杂质元素的去除。     

封口型单壁碳纳米管电子结构的密度泛函研究

采用密度泛函(DFT)的B3LYP基组和非平衡格林函数方法对封口型单壁碳纳米管及在碳纳米管外接Au电极的纳米器件的量子结构、密利根电荷分布、电子传输和态密度等特性进行了理论研究.结果发现HOMO (Highest Occupied Molecular Orbital)和LUMO(Lowest Unoccupied Molecular Orbital)间的能隙Eg=0.973 8 eV,呈现半导体特征;态密度与电子输运谱具有很好的对应关系;电子输运主要集中在能量E＜O.O eV的区域.