KEIZO HASHIMOTO(Advanced Technologies Research Laboratories Nippon Steel Corp.1618 Ida Nakahara-ku Kawasaki 211 JAPAN)
金属学报(英文版)
Gamma titanium aluminide (γ-TiAl)intermetallic compounds are spotlighted as lightweight heat-resistant materials, and have been investigated extensively to aiming commercial use.Fundamental approaches in which phase diagrams of Ti -Al -Cr and TiAl -Nb have been studied based on the experimental data and calculations , have been performed in the national project For industrial approach, ingot process and direct casting process have been developed to provide sheet form of TiAl. By these approaches, γ-TiAl base ,intermetallic compounds show a great possibility to apply in the variety of fields .However, a more detailed understanding of phase equilibrium in Ti-Al -X and the relationship between the mechanical properties and microstructure will be necessary
关键词:
: TITANIUM ALUMINIDE
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CAI Jiuju
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LU Zhongwu
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YUE Qiang
钢铁研究学报(英文版)
The industrial system should learn from the natural ecosystem. The resource utilization efficiency should be increased and the environmental load should be decreased, depending on the materials recycled in the system. The classification of industrial materials from the viewpoint of largescale recycling was stated. Recycling of materials, on three different levels, was introduced in the industrial system. The metal flow diagram in the life cycle of products, in the case of no materials recycled, materials partially recycled, and materials completely recycled, was given. The natural resource conservation and the waste emission reduction were analyzed under the condition of materials completely recycled. The expressions for the relation between resource efficiency and material recycling rate, and the relation between ecoefficiency and material recycling rate were derived, and the curves describing the relationship between them were protracted. The diagram of iron flow in the life cycle of iron and steel products in China, in 2001, was given, and the iron resource efficiency, material recycling rate, and iron ecoefficiency were analyzed. The variation of iron resource efficiency with the material recycling rate was analyzed for two different production ratios.
关键词:
recycling;industrial material;product life cycle;resource efficiency;ecoefficiency;material recycling rate
FU Jian-xun
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LI Jing-she
钢铁研究学报(英文版)
The broadening of slab was investigated on the basis of several industrial manufactures of continuous casting. The results show that slab broadening commonly exists in the process of continuous casting. It is found that there are few reports on it until now. In order to find out the reasons of slab broadening, we checked the effect of change of mold size, excepting technological parameters, conditions of soft reduction, and contraction of roll gap on slab broadening. Our examinations exclude the possibility of change of mold size, excepting technological parameters to be the causes of broadening of slab. The broadening of slab probably results from the static pressure of molten steel and the force from driving rolls. At the same time, online observations on three kinds of steel in the process of continuous casting reveal that the average objective ratio of slab broadening ranges from 1.27 % to 3.00 %, and even arrives at 4.4 %. In addition, the width of mold and formulas of calculating the broadening of slab was deduced.
关键词:
continuous casting;slab;broadening;industrial investigation
Acta Physico-Chimica Sinica
The effect of thiourea(TU) on the corrosion behavior of bulk nanocrystallized and coarse grain industrial pure iron in.1 mol . L-1 HCl at room temperature was investigated, by means of electrochemical impedance spectroscopy (EIS). Bulk nanocrystallized industrial pure iron is less prone to get corrosive than its coarse grain counterpart in blank 1 mol . L-1 HCl at room temperature from the EIS fitting results. On the basis of the variation of impedance behaviors of bulk nanocrystallized and coarse grain industrial pure iron in the inhibitor-containing 1 mol . L-1 HCl solutions with the immersion time, an relationship between immersion time and Nyquist plot was established, for very short immersion time, namely, 5 min, an inductive loop appeared at different concentrations in the Nyquist plots of coarse industrial pure iron rod, but it did not appear in those of nanocrystallized industrial pure iron. A critical concentration of thiourea with the largest R,,(charge transfer resistance) in the complex impedance plane appeared for both samples.
关键词:
bulk nanocrystallized industrial pure iron;thiourea;inhibition;electrochemical;impedance spectroscopy (EIS);hydrochloridic solution;mild-steel;electrochemical techniques;derivatives;acid
Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science
The rusting evolution of MnCuP weathering steel in a simulated industrial atmosphere as a function of corrosion duration was investigated by corrosion weight gain, scanning electron microscopy, X-ray diffraction, and electrochemical methods. The results indicate that the corrosion kinetics is related closely to the rust composition and electrochemical properties. The corrosion rate is higher during the first corrosion stage, and it is lower during the second corrosion stage. During the first corrosion stage, the rust layer is in low density, discontinuous, and loose, with a lower relative abundance of alpha-FeOOH. During the second corrosion stage, a compact and protective inner rust layer forms with a higher relative abundance of alpha-FeOOH, contributing to enhanced rust layer resistance. The rust initially enhances and then stabilizes the cathodic process, but the anodic process tends to be inhibited by the protective rust layer. Electrochemical impedance spectroscopy tests indicate that it is more scientific to evaluate the rust layer protective ability by charge transfer resistance.
关键词:
environments;mechanism
WU Tong
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CHENG Su-sen
钢铁研究学报(英文版)
Copper staves have been equipped on nearly all of BF (blast furnaces) with volume over than 1000 m3 in China since their introduction from abroad about more than 10 years ago. Because of short application and lack of experience, phenomena of thickened or naked of copper stave happen occasionally which influence production severely. So it is important to study the model of forming-accretion on BF copper stave and realize real-time monitoring of forming-accretion on different copper staves. Therefore, mathematic model of calculating accretion thickness by heat flow of BF is proposed, and the calculated results indicate that accretion thickness could be kept at a reasonable range of around 50 mm by controlling heat flux around 22.0 kW/m2. The monitoring program based on the model was applied to a certain BF in China successfully, and it is found that slip of BF near the inner wall is one of most important reasons that cause fluctuation of accretion thickness. During the period of scheduled maintenance of the certain BF, the thickness of accretion measured through the static pressure holes is in good accordance with the value calculated by the monitoring program, so the results calculated by the monitoring program can be used to guide industrial production.
关键词:
blast furnace
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copper stave
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forming-accretion
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monitor
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industrial application
Materials and Corrosion-Werkstoffe Und Korrosion
In order to investigate the galvanic anodic protection (GAP) of ferrous metals (such as 410, 304 and 316 stainless steels) in acid solutions by doped polyaniline (PANi), separate doped PANi powder-pressed electrodes with different surface areas (the area ratio of the PANi electrode to stainless steel is between 1:1 and 1:2) have been prepared. These were coupled with ferrous metal in the following solutions: 5 M sulphuric acid, 5 M phosphoric acid and industrial phosphoric acid (containing 5 M phosphoric acid and 0.05% chloride ion) to construct a galvanic cell, in which PANi is cathode while ferrous metal is anode. The results indicate that a PANi electrode with sufficient area can provide corrosion protection to stainless steel in these acidic solutions. A pilot scale coupling experiment was carried out. The results indicate that PANi is a promising material as an electrode for the anodic protection of ferrous metals in acidic solutions in industrial situations.
关键词:
conducting polymer-coatings;corrosion protection;stainless-steel;spectroscopy;passivation;performance;mechanism;behavior;primers;films
