材料期刊网

RELATIONSHIP BETWEEN PRIMARY MORPHOLOGY AND CRYSTAL STRUCTURE OF CARBIDES GROWING IN SUPERALLOYS

LIU Lin FU Hengzhi SHI Zhengxing Northwestern Polytechnical University , Xi'an , China Dr.LIU Lin Lecturer , Department of Applied Physics , Northwestern Polytechnical University , Xi'an 710072 , China

金属学报(英文版)

The SEM analysis of decply etched specimens of Ni-base superalloys K38 and K19H+Ta in- dicates that both the primary morphologies under normal growth conditions and the final morphologies near equilibrium of MC carbides are octahedral blocks.The classification of MC crystal faces by means of PBC(Periodic Bond Chains)theory confirms that{100}, {110}and{111}are F faces,and that{212}are S faces.The calculations of the attachment energy for each F face show that{111}are most easily appeared.It has also been inferred that one of the MC growth units is a coordination octahedron composed of one metal atom sur- rounded by six carbon atoms.The octahedral growth units can be attached to the growth sur- faces of MC carbides through laver stacking mechanism on the{111}faces.

关键词: carbide , null

STATISTICAL EVALUATION OF CRITICAL INCLUSION FACTOR FOR SECONDARY RECRYSTALLIZATON IN 3%Si STEEL Lecturer,Department of Materials Engineering,Southwestern Jiaotong University,Chengdu 610031,China

LI Shuchen Southwestern Jiaotong University , Chengdu , ChinaCHEN Mengzhe KE Jun University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

On the basis of statistical data of MnS in the conventional 3% Si steel sheeets after various annealing processes,the critical inclusion factor has been evaluated to be 20 mm~(-1).The inhi- bition of MnS to grain growth has been exactly described.

关键词: 3%Si steel , null , null

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,University of Science and Technology Beijing,Beijing 100083,China

QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词: stress corrosion cracking , null , null , null

新型PU-DR19-SiO2纳米复合材料的制备和表征

钟爱民 , 周钰明 , 邱凤仙

功能材料

利用溶胶-凝胶法将硅烷染料、含硅氧烷的非线性聚氨酯与TEOS共水解-缩合首先制备了新型PU-DR19-SiO2纳米复合材料,并用IR、SEM、TEM、UV-vis和DSC-TGA对其结构和性能进行了表征.结果显示:材料中有机相与无机相以共价键相连,没有发生相分离,且其中非线性较好的DR19生色团含量和材料的Tg都较纯NLO/PU有显著增加,可以用来制备性能优良的二阶非线性光学器件.

关键词: 聚氨酯 , 复合材料 , 非线性光学 , DR19 , SiO2

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

DHCR和DR一体化计划调度的体系结构研究及应用

许剑 , 吕志民 , 徐金梧 , 朱志荣 , 王岑

钢铁

针对DHCR和DR(direct hot charging rolling and direct rolling)工艺的特点,提出了一种包括批量计划层、作业调度层和动态调度层的DHCR和DR一体化计划调度三层体系结构.批量计划层包括合同计划优化模块和一体化批量计划优化模块,作业调度层包括作业调度优化模块,动态调度层包括基于规则的动态调度主控模块和实时控制器.分析了各层的结构、功能、特点和若干设计指导思想.按照该体系结构开发了武钢二热轧DHCR生产管理系统,生产计划的75%可实现直装轧制(平均装炉温度在700℃以上),加热炉产能提高了30%,同时减少了计划编制和调度所需要的时间.实际应用结果表明,该体系结构是行之有效的.

关键词: DHCR和DR , 计划调度 , 体系结构

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

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

含氟聚酰亚胺1,3-BPA-6FDA-DR1的合成及其热光性能

邱凤仙 , 杨冬亚 , 曹国荣 , 蒋艳 , 黄金华 , 李萍萍

应用化学 doi:10.3969/j.issn.1000-0518.2007.10.007

用1,3-双(3-氨基苯氧基)苯(1,3-BPA)、4,4'-(六氟异丙基)-苯二酸酐(6FDA)和分散红1(DR1)合成了含氟聚酰亚胺,采用示差扫描量热(DSC)、热失重分析(TGA)和紫外、红外吸收光谱等测试技术对该聚酰亚胺的热稳定性和结构进行了表征. 结果显示,该聚酰亚胺的玻璃化转变温度(Tg)和在5%的质量损失温度分别为238和287 ℃,表明具有较好的热稳定性. 不同浓度的材料在自然光下的热光系数(dn/dT)值为(-2.31～-3.04)×10-4/℃,体积热膨胀系数变化率(dβ/dT)为(2.56～4.32)×10-7/℃;一定浓度的材料在436 nm单波长光照射下的热光系数(dn/dT)值为-3.08×10-4/℃,体热膨胀系数变化率(dβ/dT)为4.72×10-7/℃,表明该聚合物在低驱动功率的新型数字热光开关、光通信器件等领域具有潜在的应用前景.

关键词: 聚亚酰胺 , 热光系数 , 介电常数 , 体积膨胀系数