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High-purity rare-earth metals: preparation, properties, and application

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广东有色金属学报 2005年第2期15卷 332-335页

作者： Kol chugina N.B. Burkhanov G.S. Chistyakov O.D. Burkhanov Yu.S. baikov institute of metallurgy and materials science Russian Academy of Sciences Moscow Russia

In recent years, the ever-growing interest of investigators to the study of rare-earth metals REM) is observed owing to unique properties of the metals and potential uses in electronics, laser technology, space techno... 详细信息

关键词：稀土金属纯度 REM 显微结构

Using new physics and technology to advance electrostimulated rolling of metals and alloys

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广东有色金属学报 2005年第2期15卷 530-532页

作者： Konstantin M. Kli mov Ivan I . Novikov baikov institute of metallurgy and materials science Russian Academy of Sciences Moscow119991 Russia

Electrostimulated deformation of metals and alloys, using groove or smooth rolling, requires that several important conditions are satisfied. (1) The deformation site must geometrically overlap with the flow of electric current passing through a strip between the rolls; (2) The density of direct or alternating electric current supplied to deformation site must be sufficiently high (of an order of 104-106А/cm^2); (3) An efficient heat removal from the deformation site must be achieved. In general, the temperature of a strip must be within the range of 100-300℃. (4) The electric resistance at the roll-strip interface must be minimized. Our recent studies also indicate that the electrostimulated rolling in the shortcut regime is a further condition for obtaining high quality rolling of metals. In this regime, the rolls are placed in physical contact even in the absence of a strip that ensures an uninterrupted passage of electric current between the rolls.

关键词：金属材料合金物理性能轧制工艺

Palladium-rare-earth metal alloys-advanced materials for hydrogen power engineering

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广东有色金属学报 2005年第2期15卷 409-413页

作者： Burkhanov G.S. Roshan N.R. Kol chugina N.B. Korenovskii N.L. baikov institute of metallurgy and materials science Russian Academy of Sciences Moscow119991 Russia

Hydrogen of no less than 99. 999 % (vol. fraction) purity is a principal power media of hydrogen power engineering. A single method for the preparation of high purity hydrogen consists in its separation from vapour-gas mixtures via the selective diffusion of hydrogen through a palladium membrane. The rate of hydrogen diffusion and the strength and stability during the operation in aggressive gases are important characteristics of palladium membranes. The increase in the strength, plasticity, and hydrogen-permeability of membrane alloys can be reached by alloying palladium with the formation of solid *** formation of wide ranges of palladium-rare-earth metal (REM) solid solutions is an interesting feature of palladium. Earlier, we have shown that the alloying of Pd with REM substantially increases the rate of hydrogen diffusion and markedly increases the strength of palladium on retention of the adequate *** this work, we have studied alloys of the Pd-Y and Pd-Y-Me systems. It was shown that the following conditions should be satisfied to prepare high-quality alloys exhibiting high service properties: (1)the use of high-purity components (whose purity is no less than 99.95%, mass fraction), in particular,high-purity Y prepared by vacuum distillation, and (2) holding the reached purity for the final *** this purpose, we suggested a cycle of manufacturing operations including the preparation of a vacuumtight foil of 50 (m thick as the final *** hydrogen-permeability of the alloys was measured at different temperatures and hydrogen pressures. The instability of operation of binary Pd-Y alloys w alloying the composition with a Ⅷ Group metal. For example, the alloy of the optimum composition Pd-8Y-Me in the annealed state exhibits the following mechanical properties: HV= 75 kg/mm2 , σu = 58 kg/mm2 , and δ= 20%. Its hydrogen-permeability (QH2) measured as a function of the temperature exceeds that of the Pd-23Ag alloy (that is widely used

关键词：稀土金属合金钯机械性能净化处理

Nanomaterials on the basis of electroboosted rolling in grooves and calibres

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广东有色金属学报 2005年第2期15卷 262-264页

作者： Konstantin M. Kli mov baikov institute of metallurgy and materials science russian academy of sciences Moscow119991 russia

The process of electroboosted rolling in grooves and calibres can be utilised as an effective way of obtaining of new materials with structure and properties, close to nanosizes. The features and technological capabilities of electroboosted rolling in grooves and calibres utilised for obtaining unique constructional(structural) and functional materials and hardware products from them. The cross-sectional(transversal) size of internal layers can be at the expense of repeated reduction of a package (packet) from the ordered threads or layers as metallic, and not of metallic materials.

关键词：纳米材料轧制工艺口径电化学热处理工艺

Influence of inhomogeneity of grain-boundary region of nanocristalline materials on elastic properties

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广东有色金属学报 2005年第2期15卷 164-167页

作者： Stepanov Y.N. Alymov M.I. baikov institute of metallurgy and materials sciences RAS Moscow Russia

Experimental data indicate that Young’s modulus of materials decreases with the decreasing of the grain size. Obviously, the primary factor of this decrease is presence of grain-boundary region, which Young’s modulus other than in the bulk of crystallites. There is a set of various expressions for calculation of Young’s modulus of polycrystals, obtained under the assumption, that it is possible to consider a polycrystal as a composite consisting of a crystalline matrix and a intercrystalline layers (grain-boundary region). Calculations showed incorrectness of application of a majority of these expressions and a large error in the calculations for the nanocrystalline materials. By us, on the basis of the same assumptions, is also obtained analytical expression for calculating Young’s modulus of materials with grain size more than 30 nm, which is more exact, than all *** is necessary to consider under the calculation of effective Young’s modulus nanocrystalline materials with grain size of less than 30nm, that grain-boundary region itself is not uniform. It is reliably established, that the triple joints of grain boundaries have a structure and properties, different from the structure and the properties of grain boundaries, which these joints connect. For nanocrystalline materials the volume fraction of the triple joints in the grain-boundary region can reach 50% and even more. Therefore assumption was made, that the nanocrystalline materials should be represented as consisting of three phases (triple joints, grain boundary between the triple joints and crystallite). On the basis of this idea is obtained analytical expression for calculating of Young’s modulus nanocrystalline materials. The analysis shows that Young’s modulus calculated by this analytical expression coordinated with the theory and the experiment.

关键词：弹性体多相性结构性能铸锭工艺钢

Highly effective sorbents obtained by treating agrowaste products in cold plasma

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广东有色金属学报 2005年第2期15卷 553-556页

作者： Abdullin I. Sh Kudinov V. V Kazan State Technological University Kazan 420015 Russia baikov institute of metallurgy and materials science of russia academy of sciences Moscow 19991 Russia

Sorbents are widely used in purification of various liquids and gases, offering a universal means for wastewater and air cleaning. The most promising sorbents are those obtained from agrowaste products such as rice or buckwheat husk. Processing of husk in cold plasma modifies the composition, structure and surface properties of the raw material and raises its porosity, thus substantially improving the sorption properties of the final *** as a raw material for producing sorbents has the following advantageous properties: (1) appropriate chemical composition; (2) low cost; (3) high dispersity, due to which there is no need in any special treatment of the material prior to its exposing to plasma; (4) scaly structure and developed porous surface ensuring a high surface-to-volume ratio. The best properties are displayed by the sorbents obtained in cold plasma under reduced pressures of 53.2 Pa. The raw material traverses the region occupied by the plasma and, as it does so, it gets heated up to a temperature of 250 - 350 ℃. The whole process involves two stages: combustion of the raw material and modification of its properties under the action of the plasma. The combustion proceeds due to the oxygen contained in the starting material. During the combustion, the hydrogen contained in the starting material and some part of the carbon also burn out. The resultant scaly sorbent is accumulated in a cooler. The scales are black; they range in sizes from 1mm to 5 mm. The sorbents obtained are remarkable for their useful properties and outperform most of the traditional sorbents used in modern industry. The starting materials are inexpensive, and their resources are almost unlimited. The sorbents have rather a low production cost (1.8-2.5 $/kg). The sorbents can be used for cleaning hydrosphere from water pollutants on a large scale. The degree of cleaning water surface from oil products with sorbents was a subject of investigation. The highest degree of purification th

关键词：吸附剂冷却液吸附性能空气净化废水处理

Examination and further improving of the manufacture of longitudinal electric-welded pipes

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广东有色金属学报 2005年第2期15卷 518-520页

作者： Barabantsev G Tyulyapin A Kolobov A Barabantsev M Yusupov V Traino A JSC “Severstal”. Cherepovets. Vologda region 162600 Russia A.A. baikov institute of metallurgy and materials science Russian Academy of Sciences Moscow 119991 Russia

Longitudinal electric-welded pipes of small and intermediate size in diameter are widely used in various fields from mechanical engineering to pipelines technology all over the world.

关键词：焊管钢管铸造工艺金属材料机械性能

Single-crystal tungsten-based alloys with molybdenum and rhenium

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广东有色金属学报 2005年第2期15卷 323-328页

作者： Burkhanov G.S. Kuz mishchev V. A. Kadyrbaev A. R. Kirillova V. M. Drapala J . Buinoshkova K. baikov institute of metallurgy and materials science Russian Academy of Sciences Moscow119991 Russia Visoka Skola Banska (Technical University) Ostrava Czech Republic

Single crystals of ternary W-based alloys with 2% Re and less than 7% Mo have been grown for the first time at the baikov institute of metallurgy and materials science RAS. Plasma arc melting allowed us to effectively purify the single crystals from a number of impurities. According to mass spectrometric analysis for 70 elements, the total content of impurities does not exceed 0.063%. It was found that, as the Mo content increases, the size of first-kind subgrains decreases and their mutual misorientation increases. In the W-based alloy with 2.3% Re and 6.7% Mo, no first-kind subgrains are observed, whereas second-kind subgrains are elongated along the growth direction. In this case, their total misorientation is well below that in the other low-alloy single ***-crystal of binary tungsten-based alloys with rhenium were prepared by electron-beam zone melting (1% Re, mass fraction) and plasma arc melting (2%Re,10%Re, 25%Re (mass fraction)). It was found that the low-alloyed (1%-2% Rh (mass fraction)) W-based alloys are characterized by a rather perfect single-crystal structure and misorientations of first- and second-kind subgrains of 20-50′ and 10-40′, respectively. Sections with the coarse-grained structure are observed in ingots of the alloy with 10% and 25% (mass fraction) Rh; in the alloy with 25% Rh, such structure is observed immediately from the seed.A device for measuring the liquidus and solidus temperatures of refractory metallic alloys has been designed. The liquidus temperatures of ternary single crystals (W-Mo-Re) have been *** studied single crystals, owing to their purity and high stability of the structure and properties, are widely used in electronics, electrical engineering, and analytical devices for various purposes.

关键词：钨合金钼铼单晶系理化性能

添加0.3%Sc对Al-Ca-Si共晶合金显微组织、相组成及硬化性能的影响（英文）

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Transactions of Nonferrous Metals Society of China 2017年第4期27卷 741-746页

作者： Nikolay BELOV Evgenia NAUMOVA Torgom AKOPYAN National University of science and Technology MISIS 4 Leninskiy pr. 4 Moscow 119049 Russia institute of russian academy of sciences A. A. Baikov Institute of Metallurgy and Material Science RASLeninskiy pr. 49 Moscow 119991 Russia

研究含0.3%Sc、0-14%Si和0-10%Ca铝基合金的相组成、显微组织和硬化性能。采用实验研究包括扫描电镜、热分析和硬度测试与Thermo-Calc软件模拟相结合的方法对合金的组成进行优化。结果表明,经300~500°C退火处理后合金的硬化效果最好,... 详细信息

研究含0.3%Sc、0-14%Si和0-10%Ca铝基合金的相组成、显微组织和硬化性能。采用实验研究包括扫描电镜、热分析和硬度测试与Thermo-Calc软件模拟相结合的方法对合金的组成进行优化。结果表明,经300~500°C退火处理后合金的硬化效果最好,这是由于Al3Sc纳米颗粒的析出及其进一步粗化。成分在(Al)+Al_4Ca+Al_2Si_2Ca相区的合金呈现明显的硬化效应。三元共晶合金(Al)+Al_4Ca+Al_2Si_2Ca比Al-Si共晶合金的显微组织细得多,这表明实验合金相对于A356系列工业合金具有更高的力学性能。与A356系列合金不同,实验合金不需要淬火处理,因为在其铸件的退火过程中形成了硬化粒子。

关键词： Al-Ca-Si-Sc 系列合金共晶 Al3Sc 纳米颗粒相组成显微组织热处理硬化