我国电容器级钽丝发展与展望

回顾了我国电容器级钽丝发展历程，描述了我国钽丝发展现状和技术发展历程及其在世界钽工业发展中所处的地位和竞争能力，阐明了我国钽丝加工技术领域中所存在的问题和面临的形势。从国家行业整体发展角度考虑，提出了对国内钽丝行业进行重组整合和积极开发具有自主知识产权技术的可持续发展的战略构想。     

钽铌资源及中国钽铌工业的发展

详细综述了国内外钽铌资源的储量、特点、品位和分布及世界钽铌产品的结构、消耗数量及应用领域.着重介绍了我国钽铌在采矿、选矿、冶金和钽铌金属加工方面的技术进步和创新.最后作者对我国钽铌事业的发展提出了建设性的意见.     

2007年钽铌工业发展评述

评述了2007年中国钽铌工业的运行状况.在世界钽铌产品总需求持续增长的带动下,中国钽铌工业继续保持良好的增长势头,工业生产总值达到22.79亿元,销售收入达到23.37亿元,分别比上年增长了27.9%和28.8%.2007年是中国钽铌工业快速发展的一年,矿产量和冶炼品产量增加,高端钽铌产品的加工和出口快速增长.最后分析了中国钽铌工业发展中存在的突出问题,并提出了促进行业发展的措施.     

我国电容器级钽丝的发展

回顾了我国电容器级钽丝发展历程,评述了我国电容器级钽丝发展现状、技术发展历程以及在世界钽工业发展中所处的地位,分析了我国钽丝加工技术领域存在的问题,就我国钽丝行业发展提出通过政府协调、政策引导和市场机制的综合运用,实现钽丝行业的有效整合,构筑技术创新和人才竞争机制,密切关注钽丝市场的需求动态,加大技术研发投入,强化自主知识产权的保护意识,使我国钽丝行业健康、有序地持续发展.     

2006年中国钽铌工业发展述评

评述了2006年中国钽铌工业的运行状况.在世界钽铌产品总需求持续增长的带动下,中国钽铌工业也呈现出良好的增长势头,总产值达到17.82亿元,销售收入达到18.15亿元,与2005年相比分别增长了23.58%和20%.中国电容器用钽粉和钽丝的质量已接近国际先进水平,产量已分别占世界产量的21%和56%以上,出口总量达到总产量的90%以上.最后分析了中国钽铌工业发展中存在的突出问题,并提出了促进行业发展的措施.     

西安优耐特容器制造有限公司

正西安优耐特容器制造有限公司位于国家级西安经济技术开发区径渭工业园,是一家专业从事稀有金属装备研发、设计、制造、销售、服务为一体的高新技术企业,是西部金属材料股份有限公司(西部材料,股票代码"002149")的控股子公司,其前身为西北有色金属研究院爆炸与焊接研究所。公司依托西北有色金属研究院稀有金属材料研究和西部材料公司在钽、铌、锆、钛、镍及其合金材料的研究、加工优势,先后为国内外客户提供1000余台套稀有金属重点设备,其中:钽、铌设备制造技术处于世界领先水平;钛、锆、镍及其合金设备制造技术国内一流。产品广泛应用于航空、航天、国防、石油、化工、冶金、化纤等行业,并出口欧美及东南亚等地区。     

对我国钽铌企业积极分享境外资源的分析

介绍了国外钽铌原料供应种类和特征,分析了我国钽铌资源的特点及近几年来供需状况,评述了我国企业积极开发境外钽铌资源的意义、方式及风险.指出在当前环境下,由于发达国家加强了对发展中国家资源的控制力度,加大了我国钽铌企业开发境外矿产资源的难度.尽管这样我国钽铌企业也应该积极开发境外资源,建立稳定的原料供应基地,赢得更大的市场与发展空间,同时还可获取资源开发的高额利润.这是企业可持续发展的必由之举.     

钽、铌资源的分布与原料的供需状况

对钽、铌资源的分布及特征进行了论述,对目前规模以上的钽矿山和铌矿山进行了介绍和论述,在此基础上对近年来世界钽和铌原料的需求与供应种类、供应数量等状况进行了阐述.     

国家钽铌特种金属材料工程技术研究中心在宁夏成立

经国家科技部批准，国家钽铌铍稀有色金属材料领域和我区工业领域第一家国家级工程技术研究中心——国家钽铌特种金属材料工程技术研究中心在宁夏东方有色金属集团正式成立。该中心将主要围绕特种金属资源综合利用技术、特种金属材料及合金的冶金与加工技术，重点突破特种金属材料的冶炼与加工关键技术，进行工程化研究开发和成果转化，     

我国第一个钽铌铍企事业单位辉煌的36年—宁夏有色金属冶炼厂及西北稀有金属材料研究的发展历程

宁夏有色金属冶炼厂及西北稀有金属材料研究院 (以下简称厂院 ) ,是我国第一个钽、铌、铍企事业单位。 30多年来 ,厂院经历了第一次创业 ,实现了钽、铌、铍产业化 ,填补了我国钽铌电子功能材料 ,国防军工用高性能铍材等空白 ;第二次创业 ,不断推进技术进步 ,形成规模生产 ,走向世界市场 ,建立现代企业制度 ,成立宁夏东方钽业股份有限公司 ,跻身世界钽业三强 ,实现了由小到大 ,由军到民 ,由内到外 ,由弱到强的转变 ,促进了中国钽、铌、铍工业的腾飞。厂院创业之初 ,有职工 2 0 0余人 ,固定资产约 5 0 0万元 ,产品只有氟钽酸钾、氧化铌、钽粉…     

电容器用钽铌粉的研究进展

概括介绍了电容器用钽铌粉的研究进展,介绍了钽粉的3种钠还原制备方法的化学反应机理并进行了比较,同时还介绍了铌粉的制备方法,包括铝热还原法、电解还原法、蒸气还原法、钠还原法和金属热还原法;阐述了钽铌粉中杂质的测定方法以及有关钽铌粉的其它研究进展.     

Reactions of V<Subscript>2</Subscript>O<Subscript>5</Subscript>, Nb<Subscript>2</Subscript>O<Subscript>5</Subscript>, and Ta<Subscript>2</Subscript>O<Subscript>5</Subscript> with AlN

Reactions of vanadium, niobium, and tantalum pentoxides with aluminum nitride have been studied using X-ray diffraction. At temperatures from 1000 to 1600°C, we have identified various V, Nb, and Ta nitrides. The composition of the niobium and tantalum nitrides depends on the reaction temperature. The tendency toward nitride formation becomes stronger in the order V₂O₅ < Ta₂O₅ < Nb₂O₅.     

Elaboration of mixed tantalum and niobium carbides from tantalite mineral (Fe,Mn)(Ta1−x Nbx)2O6

This paper presents an original method of synthesis of mixed tantalum and niobium carbides from an oxalic precursor elaborated from the tantalite mineral (Fe,Mn)(Ta_1–x Nb _x )₂O₆. The process of elaboration consists initially in melting the ore with potassium pyrosulphate, then performing a lixiviation with a concentrated hydrochloric acid solution. During the latter reaction, iron and manganese oxides are converted into water-soluble chlorides while the fused mass containing potassium, niobium and tantalum is not dissolved. Traces of chlorides are eliminated by filtration with boiling aqueous solution. Then, the solid is dissolved slowly in hot concentrated sulphuric acid solution. Adding ammonium hydroxide up to a pH of 8 completes the precipitation of niobium and tantalum hydroxides. The precipitate (Ta_1–x Nb _x )(OH)₅ is washed and submitted to a reaction of complexation with oxalate ions in an aqueous environment. This reaction involves the formation of a water-soluble oxalic complex containing tantalum and niobium. The excess of water is eliminated by evaporation at 333 K. The tantalum and niobium carbides are obtained by submitting the oxalic complex of chemical formula (NH₄)₃(Ta_1–x Nb _x )O(C₂O₄)_3· nH₂O to a gas-solid reaction in a methane-hydrogen atmosphere at 1273 K. The oxalic precursor and their resultant mixed carbides are characterized by atomic absorption and Infra-Red spectroscopies, thermogravimetric-differential thermal analysis coupled, laser granulometry, X-ray diffraction and transmission electronic microscopy.     

Sondermetalle und ihre Anwendung im Chemieapparatebau

Refractory Metals and their Application in the Chemical Process Industry Special metals, such as titanium, zirconium and tantalum, are being used increasingly for chemical plant. The exceptional resistance of special metals to many corrosive chemicals - they show it even at high temperatures and pressures - arises not from natural immunity but from the formation of a protective oxide passive layer on the metal surface. Special metals are well suited for welding. Their reactions with gases of the atmosphere must be taken into account though. Welding is therefore possible only under inert gas or a high vacuum. Similarly, alloying with iron-based materials during welding must be avoided under all circumstances. It should be taken into consideration that the melting point of tantalum, for example, is about twice as high as that of steel. Tantalum and niobium are machined with high-speed cutting steels; the cutting speed and cutting angle are similar to those used for stainless steels. In detail, the outstanding properties of special metals in chemical plant are as follows:

• — the stability of titanium under oxidizing conditions
• — the stability of zirconium under reducing and alkaline conditions
• — the resistance of molybdenum to hydrofluoric acid and fluoride
• — the stability of tantalum under oxidizing and reducing conditions.

In pure mineral acids the passive behaviour generally improves in the order titanium - zirconium - tantalum. Except where molybdenum is concerned, the medium should not contain fluoride. The material with the widest range of applications is tantalum. The addition of niobium as an alloying element leads to favourably priced but similarly resistant materials whose prospects of becoming established in the chemical industry and playing a part similar in importance to that of tantalum itself are good.     

南平钽铌矿环境γ辐射监测

钽铌矿开发是伴生放射性矿资源开发利用项目,放射性污染防治是钽铌矿开发的环境保护重点。对南平钽铌矿采选一期工程(600t/d)监测表明,钽铌矿的开发后放射性主要集中在钽铌精矿中,而矿区周围环境γ辐射水平与开发前比较无明显变化。     

Oxygen adsorption on the (110) face of tantalum,niobium, molybdenum and tungsten single crystals

Preliminary surface studies using work function techniques are reported for the (110) face of the refractory metals tantalum, niobium, molybdenum and tungsten, both in the clean state and during the introduction of pure oxygen gas at room temperature. The conclusions of Haas et al from LEED measurements on the same group are substantiated. The surface potential changes as a function of exposure for tantalum and niobium are very similar but quite different from molybdenum and tungsten which are also similar. The latter show a two phase adsorption, both of which are electronegative, the former an initial electronegative phase followed by a pressure dependent electropositive phase. Solution of oxygen into the bulk probably takes place for tantalum and niobium to give rise to the electropositive state. Differences in atomic size are small for all four metals and thus the observed groupings are probably a consequence of chemical effects and similarities existing between members of groups VB and VIB.     

直流电弧发射光谱法测定铌及铌合金中钽含量

采用直流电弧光谱仪对铌及铌合金中钽元素进行检测。通过试验确定满足分析条件的缓冲剂、样品与缓冲剂的配比及钽元素谱线并检测其精密度、准确度及检出限。结果表明,选择Li2CO3与碳粉1∶6混合作为缓冲剂,缓冲剂与样品比例为1∶2,钽元素的谱线为271.013 nm;加标回收率为94%~109%,测定值的相对标准偏差(测10次)均小于10%。     

Mechanical properties of Nb2O5 and Ta2O5 prepared by different procedures

We have studied the mechanical properties of niobium pentoxide and tantalum pentoxide ceramics prepared by a conventional ceramic processing technique and by exposure to high-intensity light (HIL). The results demonstrate that, after HIL exposure in an optical furnace, the niobium pentoxide and tantalum pentoxide ceramics possess enhanced microhardness and improved mechanical properties (strength, fracture toughness, and brittle microstrength) owing to the formation of fractal micro- and nanostructures. With increasing exposure intensity, the strength of the Nb₂O₅ and Ta₂O₅ ceramics increases.     

Criteria for Selecting Substrates for Nb<Subscript>3</Subscript>Sn Electrodeposition

We studied the effect of substrate material on the microstructure and properties of Nb₃Sn coatings produced by electrochemical coreduction of Nb and Sn ions in the cathodic zone in molten salts. The results demonstrate that continuous superconducting Nb₃Sn coatings can be produced on molybdenum, tantalum, niobium, copper, nickel, Invar and the 60% Ni + 22% Mo + 12% Fe alloy. The coatings grown on molybdenum, tantalum, and niobium have the highest purity. To ensure good superconducting properties of electrodeposited coatings, preference should be given, all other factors being the same, to substrate materials with thermal expansion coefficients close to or smaller than that of Nb₃Sn.     

Attenuation of ultrasonic waves in V, Nb and Ta at low temperatures

Variation of ultrasonic attenuation and velocities with temperature have been evaluated in the temperature range 5-50 K due to electron-phonon interaction mechanism in transition metals vanadium, niobium and tantalum for longitudinal and shear waves. For this evaluation, we have also computed the second order elastic constants using Morse potential. Behaviour of acoustical phonons in these bcc metals is different from other normal metals, intermetallics, semimetallics and alloys. Some characteristic features of these materials connected to ultrasonic parameters are discussed.