材料期刊网

SULFIDATION OF Co-15wt%Y ALLOY IN H_2-H_2S MIXTURES AT 600-800℃

NIU Yan , F.GESMUNDO , WU Weitao , ZENG Chaoliu , F.VIANI , (State Key Laboratory for Corrosion and Protection , Institute of Corrosion and Protection of Metals , Chinese Academy of Sciences , Shenyang.110015 , China)(Istituto di Chimica , Facolta'di Ingegneria , Universita'di Genova , Fiera del Mare , Pad.D , 16129 Genova , Italy)Manuscript received 3 July 1995

金属学报(英文版)

The corrosion properties of a Co-15wt% Y alloy were studied in H_2-H_2S mixtures under a sulfur pressure of 10-3 Pa at 600-800℃ and of 10-2 Pa at 800℃ to examine the effect of Y on the resistance of pure cobalt to sulfur attack at high temperatures.The alloy is nearly single-phase.containing mostly the intermetallic compound Co17Y2 plus a little amount of the solid solution of Y in cobalt.At 600-700℃ and at 800℃ under 10-2 Pa of S2 the alloy forms multi-layered scales consisting of an outer region of pure cobalt sulfide,an intermediate region of a mixture of the sulfides of the two metals and finally an innermost layer of a mixture of yttrium sulfide with metal cobalt.At 800℃ under 10-3Pa of S2,below the dissociation pressure of cobalt sulfide, the alloy forms only a single layer composed of a mixture of metallic cobalt with yttrium sulfide.Pure Y produces only the oxysulfide Y2O2S, as a result of the good stability of this compound and of the presence of some impurities in the gas mixtures used The corrosion kinetics is generally rather complex and irregular except al 800℃under 10-3 Pa of S2.The addition of yttrium always reduces the sulfidation rate of cobalt, even though the formation of a continuous protective external layer of yttrium sulfide is never achieved.The internal sulfidation of Y in Co-15% Y is not associated with a depletion of Y in the alloy.This kind of diffusionless internal attack is typical of alloys with a very small solubility of the most reactive component Y in the base metal A.which restricts severely the Y flux from the alloy towards the alloy-scale interface.

关键词: :cobalt-yttrium alloy , null , null

Introduction to atmospheric corrosion research in China

Science and Technology of Advanced Materials

In this paper, we introduce the research on atmospheric corrosion in China. We describe the climate characteristics and the classification of atmospheric corrosivity across the whole country. We also describe the rusting evolution under simulated wet/dry cyclic conditions. (C) 2007 NIMS and Elsevier Ltd. All rights reserved.

关键词: atmospheric corrosion;corrosivity;rusting evolution;weathering steels;rust;mechanism;so2;o-3;no2

Recent Advances of Laser Coating Technology in China

LIANG Yong LI Ruiguo Institute of Metal Research , Academia Sinica , Shenyang 110015 , ChinaInstitute of Corrosion and Protection of Metals , Aademia Sinica , Shenyang , 110015 , China

材料科学技术（英文）

Recent advances in laser coating technology including laser cladding,laser surface alloying and laser vapour deposition in China are reviewed in this paper.

关键词: laser , null , null , null , null

Deformation-induced gamma -> DI-alpha(2) phase transformation occurring in the twin-intersection region of TiAl alloys

Journal of Materials Research

Deformation-induced gamma -> DI-alpha(2) phase transformation was verified to occur in the twin-intersection region of a Ti-45Al-8Nb (at.%) alloy compressed at room temperature. High-resolution image observations of the deformation-induced DI-alpha(2) phase suggested that the orientation relationship between the DI-alpha(2) and gamma phases remained the typical one: (0001)(DI-alpha 2)//{111}(gamma), [11 (2) over bar0](DI-alpha 2)//< 101]gamma. The conversion of stacking sequence from ordered face-centered tetragonal to ordered nonequilibrium hexagonal close-packed structure was accomplished by the movement of a/6 < 11 (2) over bar] Shockley partial dislocations on every other {111}(gamma) plane. Compositional analysis based on energy dispersive spectra revealed that the DI-alpha(2) phase had the same composition as the matrix gamma phase. No compositional diffusion Occurred because the plastic deformation was carried out at room temperature. The strong stress concentration in the intersection region was the major force to induce the gamma -> DI-alpha(2) phase transformation in the process of room-temperature compression.

关键词: titanium aluminides;mechanical-properties;room-temperature;microstructure;intermetallics;microscopy;nb

DI材横向厚差自动控制算法及其应用

徐江华 , 李山青

上海金属

DI材是宝钢的重要产品,主要用于碳酸饮料罐和啤酒罐.DI材沿宽度方向的厚度均匀性要求十分严格.为了减少DI材的横向厚差,开发了横向厚差自动控制系统并应用在某冷连轧机上.该控制系统使用了基于鲁棒性能指标(robustness specification)的横向厚差自动控制算法,从而使厚度0.229 mm以下的DI材的横向厚差被控制在±4μm以内.

关键词: DI材 , 冷轧 , 横向厚差 , 自动控制

高速电镀锡薄钢板(DI材)用气相缓蚀剂的研究

王新葵 , 罗广求 , 李宁

腐蚀与防护 doi:10.3969/j.issn.1005-748X.2005.05.003

采用气相快速甄别实验和电化学方法研究了对高速电镀锡薄钢板(DI材)具有缓蚀作用的四种不同的物质.结果表明:苯甲酸钠、苯甲酸铵、肉桂酸对DI材的阳极过程有明显的抑制作用;单纯的钨酸钠对DI材的缓蚀效果不佳.通过正交试验发现:苯甲酸钠、苯甲酸铵、肉桂酸与钨酸钠的复配使用,表现出很好的协同作用,从而得到了一种新的环保、高效的用于DI材的气相缓蚀剂配方.

关键词: 气相缓蚀剂 , 正交实验 , 协同作用

Development of Cast Superalloys for Gas Turbines in China

CHEN Rongzhang CHEN Wanhua Institute of Aeronautic Materials , Beijing 100095 , China.

材料科学技术（英文）

As in other countries,significant achievements in the research of cast superalloys for many years have also been obtained in China.These results are important contribu- tion to the development of aero and land-based gas tur- bine engines.

关键词: cast superalloy , null

Growth Mechanism of Di®erent Morphologies of ZnO Crystals Prepared by Hydrothermal Method

Hu Wang Juan Xie Kangping Yan Ming Duan

材料科学技术（英文）

Different morphologies of zinc oxide (ZnO), including microrods, hexagonal pyramid-like rods and flower-like rod aggregates, had been synthesized, respectively, on glass substrates by controlling the reaction conditions (such as precursor concentration, reaction time and pH value) of hydrothermal method. The morphologies of the as-obtained ZnO were observed with scanning electron microscopy and transmission electron microscopy.
Also, the crystalline natures of di®erent ZnO crystals were analyzed with X-ray diffraction. The possible growth mechanism of ZnO crystals with di®erent morphologies was discussed.

关键词: Zinc oxide

R&D STATUS ON INTERMETALLICS IN CHINA

CHEN Guoliang(State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 , China)SHI Changxu (Academia Sinica , Beijing 100864 , China)

金属学报(英文版)

This paper briefiy introduces the R&D of intermetallics in China. R&D on intermetallics in a national scale in China began near ten years ago. The investigation in past years focused on the fundamental research and materials development. A significant progress has been made. Various components that made of Ti3Al Ni3Al, TiAl and Fe3Al have been successfully manufactured Some of them have been evaluted. It is expected that some intermetallic alloys will be produced in an industrial scale in the near future.

关键词: :intermetallic alloys , null , null , null

Further development of NdFeB magnet industry in China

Yang LUO

材料科学技术（英文）

Due to continued growth in key markets, a broadening of application base and performance improvements, the market demands of NdFeB magnet increased steadily in 1998, and the global output of sintered NdFeB magnet exceeded 10,000 t, in spite of the economic recession in Asia. In 1998 China produced 3,850 t sintered NdFeB block magnet, with an annual growth rate of +22% over the output in 1997.

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