钨、钼、钒氧化物直接合金化生产M2高速钢

论述了采用白钨矿、氧化钼和五氧化二钒代替钨铁、钼铁和钒铁冶炼W6Mo5Cr4V2 (M2 )高速工具钢的理论依据和可行性 ,介绍了冶炼工艺技术条件 ,产品性能测试和效益分析等方面的内容。实验表明 ,在中频感应炉上采用白钨矿、氧化钼和五氧化二钒直接还原合金化生产M2高速钢的新工艺顺行 ,产品化学成分合格。合金元素回收率高 ,其中 ηw97.0 8%、ηMo96 .5 1%、ηv93.79%。M2钢质量优良 ,HRC高达 6 2 .2 ,冲击韧性αk>4 9kJ cm2 ,夹杂评为 0 .5级 ,显微组织均匀、致密。而且具有显著的经济效益和社会效益 ,新工艺可以在生产中推广应用。     

钒渣直接合金化

钒渣直接合金化工艺的基本方法是将转炉或雾化炉吹炼出的钒渣(含V_2O_515—20％)经过破碎,混入一定量的还原剂(如硅铁、铝等)再加入其它添加剂(如萤石等)制成混合料,在出钢时顺钢流加到钢包内,用电炉生产时还可将钒渣直接加到炉内,完成钒合金化的要求。使用该工艺可省去冶炼钒铁合金的生产工艺,简化流程,节省大量电耗和原材料消耗,还可较大幅度降低钒钢生产成本。据统计,转、平炉钢包内     

高钙钒渣直接冶炼钒铁的试验

我国是一个富钒国家,蕴藏着极为丰富的钒钛磁铁矿资源。钒作为合金元素加入钢中能使钢的强度提高,钢的晶粒细化,消除钢的过热倾向,并可改善钢的赤热硬性、耐磨及焊接性能,所以钒是使钢合金化的最重要的元素之一。钒作为合金元素常以钒铁形式加入钢中。 目前国内外现有的钒铁生产一般都是采用湿法提纯——火法冶炼这一工艺流程。这种工艺流程可以生产出含钒高、含杂质低的钒铁,但存在着化工原料消耗大、工艺复杂、流程     

待发表文章摘要预报

转炉冶炼过程中合金成分控制模型龚　伟 ,姜周华 ,郑　万 ,陈念铀通过对转炉冶炼过程脱氧和合金化过程的分析 ,采用参考炉次法处理合金元素收得率参数 ,并采用多元线性规划方法对合金化操作进行最优化计算 ,得到工程实用的脱氧和合金化控制模型·通过该模型的应用 ,可以保证按照各钢种成分要求实现准确、经济地进行转炉出钢时脱氧和合金化操作 ,使钢水成分达到要求范围 ,实现钢水的窄成分控制·冷连轧动态变规格在线过程控制原理与应用王军生 ,矫志杰王军生 ,赵启林王军生 ,刘相华根据国内某 1 2 2 0冷连轧机组生产实际情况采用逆流直接求解…     

含氮风吹氮合金化

氮在阀门钢、部分不锈钢中是重要的合金元素，在这些含氮钢的冶炼过程中利用氮气作合金剂对钢液进行合金化，可明显降低冶炼成本，是含氮钢冶炼的一项新技术。在理论分析计算含氮钢吹氮气增氮的热力学和动力学条件的基础上，试验研究了10kg感应炉内阀门钢、不锈钢、高锰钢粗钢液顶吹氮合金化的效果，结果表明：对阀门钢、不锈钢等，向钢液顶吹氮27－40min，可使钢液中氮含量增至其规格成分范围内，但要采取措施防止氮在钢液浇注、凝固等过程中逸出。     

用铌渣在电炉中冶炼含铌低合金钢

我国包头铁水提铌所得铌渣,以往是先在电炉中炼制成低级铌锰铁,然后用做冶炼含铌低合金钢的合金化添加剂。为了经济合理地回收利用包头铁水提铌铌渣,并降低含铌低合金钢添加铌元素的成本,本项工作用铌渣代替铌铁在电炉中冶炼含铌低合金钢。北京钢铁学院首先进行了铌渣直接合金化的热力学研究和实验室工艺试验。在此基础上,由包头东风钢铁厂提供含Nb_2O_5 4～7％的铌渣,在石家庄钢铁厂5吨电孤炉中(出钢量12吨)按16MnNb钢种冶炼9炉,总计114吨钢。工业试验结果表明,钢中铌的实际收得率稳定在70～82％。试验钢锭全部轧成φ14圆钢,经检验,机械性能符合GB1591—79     

直接应用氧化钼块作合金剂冶炼合金钢

北京钢厂、北京第二通用机械厂、北京铁合金厂和北京钢铁研究院在电炉和平炉上,进行了直接应用氧化钼块作合金剂冶炼合金结构钢的试验,取得良好效果。试验是在公称容量为0.5吨,3吨的电炉和35吨的平炉上进行的。冶炼了5CrMnMo、12CrMoA、15CrMo、12Cr_2MoWVB 和35SiMn_2MoV 等合金结构钢共224吨,其中电炉冶炼7炉,平炉冶炼4炉。他们通过试验认为,凡是需要用钼铁生产合金钢的部门,均可采用氧化钼块来代替,以减少     

酸浸法提钒新工艺的研究

研究了用稀硫酸直接浸出—萃取—反萃—氨水沉钒—煅烧的提钒工艺。结果表明,采用稀硫酸直接浸出,原矿渣中总钒的一次浸取率可达95%以上;用萃取-反萃方式净化和浓缩浸出液,同时使用萃取促进剂处理酸浸液,使萃取效率比传统方法有明显提高,萃取级数大大减少;沉钒步骤摒弃了传统的铵盐沉钒工艺,使用氨水直接沉钒,提高了产品的纯度。钒的总回收率达86%以上,比传统提钒工艺效率提高了20%以上,同时由于避免了焙烧从而解决了传统提钒过程中因焙烧等产生的HCl、Cl₂等污染问题。     

钒含量对PD3钢碳化钒析出的影响

为了弄清钒在珠光体组织转变中的作用和沉淀析出的规律,通过电化学萃取分析结合透射电子显微镜观察研究了钒含量对PD3钢中碳化钒析出行为的影响。研究结果表明：PD3钢的铁素体和渗碳体中固溶钒的饱和溶解度分别为0．09％和0．23％左右;当钢中钒含量低于0．21％时,钒主要以固溶形式存在,只有极少量的碳化钒质点无序析出;当钢中钒含量增加,超过饱和溶解度后,多余的钒则主要以碳化钒的形式析出;当钢中钒含量高于0．21％,达到0．33％时,碳化钒将以无序状态和“相关沉淀”两种方式大量析出。     

半钢增碳脱硫试验研究

用电石粉作增碳剂 ,AD粉作脱硫剂 ,对高钛渣冶炼半钢进行了增碳脱硫试验研究 ,结果表明 :半钢在 1 5 5 0℃增碳处理 ,含碳量由 2 .0 2 8%增至 3.0 39% ;在 1 5 30℃脱硫处理 ,含硫量由 0 .2 61 %减至 0 .0 1 9% ;半钢经增碳脱硫处理后可用作炼钢生铁和铸造生产生铁 ,并有较好的经济效益。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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