材料期刊网

Abrasive Wear Characteristics of Carbon and Low Alloy Steels for Better Performance of Farm Implements

M.Kumar and R. C Gupta(Centre of Advanced Study , Dept. of Metallurgical Engineering , Institute of Technology , Banaras Hindu University , Vaanasi -221 005 , India)

材料科学技术（英文）

The low stress abrasion behaviours of heat treated mild, medium carbon and high C - low Cr steels, which are generally used in making farm implements, have been investigated. The simple heat treatment greatly improves the hardness, tensile strength and abrasion resistance of medium carbon and high C - low Cr steels. The results indicate that the material removal during abrasion is controlled by a number of factors, such as hardness, chemical composition, microstructure and heat treatment conditions. The conclusion is that the heat treated high C - low Cr steel and mild steel carburized by using coaltar pitch provide the best hardness and abrasion resistance and thus appear to be the most suitable materials for making agricultural tools.

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用DEPT135测定Resol的组成及微细结构参数

杨金瑞 , 余尚先 , 顾江楠

高分子材料科学与工程

通过对resol(羟甲基酚化合物和低分子量羟甲基酚树脂)DEPT135图谱的分析讨论,得到一系列计算resol微细结构参数的经验公式.根据DEPT135图谱可判断是否发生缩聚反应,根据经验公式可计算酚单体各个活性点参与反应百分率或酚羟基导入率、不同类型缩聚所占百分率及低分子量羟甲基酚树脂的平均核体数.

关键词: 羟甲基酚化合物 , 羟甲基酚树脂 , DEPT135 , 结构参数

Service Performance of Engineering Materials

Andrej Atrens

材料科学技术（英文）

Corrosion research by Atrens and co-workers has made significant contributions to the understanding of the service performance of engineering materials. This includes: (1) elucidated corrosion mechanisms of Mg alloys, stainless steels and Cu alloys, (2) developed an improved understanding of passivity in stainless steels and binary alloys such as Fe-Cr, Ni-Cr, Co-Cr, Fe-Ti, and Fe-Si, (3) developed an improved understanding of the melt spinning of Cu alloys, and (4) elucidated mechanisms of environment assisted fracture (EAF) of steels and Zr alloys. This paper summarises contributions in the following: (1) intergranular stress corrosion cracking of pipeline steels, (2) atmospheric corrosion and patination of Cu, (3) corrosion of Mg alloys, and (4) transgranular stress corrosion cracking of rock bolts.

关键词: Stress corrosion cracking , null , null

ELECTROCHEMICAL MEASUREMENTS OF COMPONENT ACTIVITIES IN METALLURGICAL SLAGS

O. Volkova , P.R.Scheller , D.Janke

金属学报(英文版)

The up-to-date status of FeO, CaO, SiO2, P2O05,Ti2O3 and Cr2O3 activity measurements in metallurgical slags using electrochemical sensors is outlined. A description of theoretical concepts and practical sensors is presented including their determining features.

关键词: electrochemical measurement , null , null

Thermo electrochemistry and its application to metallurgical research

Zheng FANG , Quanru ZHANG , Hengzhong ZHANG , Yuan FANG

材料科学技术（英文）

The thermoelectrochemistry (TEC), a novel cross discipline, is presented, including the basic equations for a cell and a half-cell reaction, the treatment of experimental data and its application to electro-generative leaching of mineral and to measuring thermodynamic and kinetic data of an electrode reaction. The TEC technology will play an important part in the research on the metallurgical process under various fields.

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Biomimicry of bamboo bast fiber with engineering composite materials

Materials Science & Engineering C-Biomimetic Materials Sensors and Systems

Bamboo, one of the strongest natural structural composite materials, has many distinguishing features. It has been found that its reinforcement unit, hollow, multilayered and spirally-wound bast fiber, plays an extremely important role in its mechanical behavior. In the present work, on the basis of the study on bamboo bast fiber and wood tracheid, a biomimetic model of the reinforcing element, composed of two layers of helically wound fiber, was suggested. To detect the structural characteristics of such a microstructure, four types of macro fiber specimens made of engineering composites were employed: axially aligned solid and hollow cylinders, and single- and double-helical hollow cylinders. These specimens were subjected to several possible loadings, and the experimental results reveal that only the double-helical structural unit possesses the optimum comprehensive mechanical properties. An interlaminar transition zone model imitating bamboo bast fiber was proposed and was verified by engineering composite materials. In our work, the transition zone can increase the interlaminar shear strength of the composite materials by about 15%. These biomimetic structural models can be applied in the design and manufacture of engineering composite materials.

关键词: bamboo;bast fiber;biomimetics;engineering composites

Strengthening Materials by Engineering Coherent Internal Boundaries at the Nanoscale

Science

Strengthening materials traditionally involves the controlled creation of internal defects and boundaries so as to obstruct dislocation motion. Such strategies invariably compromise ductility, the ability of the material to deform, stretch, or change shape permanently without breaking. Here, we outline an approach to optimize strength and ductility by identifying three essential structural characteristics for boundaries: coherency with surrounding matrix, thermal and mechanical stability, and smallest feature size finer than 100 nanometers. We assess current understanding of strengthening and propose a methodology for engineering coherent, nanoscale internal boundaries, specifically those involving nanoscale twin boundaries. Additionally, we discuss perspectives on strengthening and preserving ductility, along with potential applications for improving failure tolerance, electrical conductivity, and resistance to electromigration.

关键词: strain-rate sensitivity;stacking-fault energy;nano-scale twins;cu-al;alloys;nanocrystalline metals;mechanical-properties;activation;volume;copper;deformation;behavior

Crystal facet engineering of semiconductor photocatalysts: motivations, advances and unique properties

Chemical Communications

Crystal facet engineering of semiconductors has become an important strategy for fine-tuning the physicochemical properties and thus optimizing the reactivity and selectivity of photocatalysts. In this review, we present the basic strategies for crystal facet engineering of photocatalysts and describe the recent advances in synthesizing faceted photocatalysts, in particular TiO(2) crystals. The unique properties of faceted photocatalysts are discussed in relation to anisotropic corrosion, interaction dependence of adsorbates, photocatalytic selectivity, photo-reduction and oxidation sites, and photocatalytic reaction order. Ideas for future research on crystal facet engineering for improving the performance of photocatalysts are also proposed.

关键词: shape-controlled synthesis;exposed 001 facets;rutile tio2 nanorods;visible-light photocatalysis;solvent-solute interactions;anatase;titanium(iv) oxide;low-temperature synthesis;ordered solid-phases;platinum nanocrystals;hydrogen-production

Jet Behavior and Metallurgical Performance of Innovated DoubleParameter Oxygen Lance in BOF

YUAN Zhangfu , YANG Xiao , LU Zhixing , HUANG Jiangning , PAN Yifang , MA Enxiang

钢铁研究学报(英文版)

A doubleparameter oxygen lance used in a 300 t converter was designed to improve the metallurgical performance. A smallscale measurement of the jet behavior was done using a computer controlled scanning system. The experimental data on the velocity distribution at the jet centerline, the contour map of the jet velocity, the deviation of the jet centerline, and the velocity distribution of the axial section were compiled. According to the results of the smallscale measurement, the doubleparameter lance was also employed for a BOF experiment. The metallurgy indexes show that the metallurgical performance was highly promoted by use of the doubleparameter lance.

关键词: oxygen lance;jet behavior;BOF;metallurgical performance

Study on compression behavior of porous magnesium used as bone tissue engineering scaffolds

Biomedical Materials

In this work, porous magnesium (Mg) with a three-dimensional open-cellular structure, potentially employed as bone tissue engineering scaffolds, was fabricated by the mechanical perforation method. The influences of porosity, pore size and pore arrangement on compressive behavior and the anisotropy of new porous Mg were analyzed theoretically using orthogonal arrays and the finite element method (FEM). The results showed that the parameters of porosity, pore size and pore arrangement had different effects on the compressive properties. The compressive strength could be improved by optimizing these parameters. The anisotropy of porous Mg was also verified in this study. The theoretical results showed good agreement with the experimental ones before the strain reaches 0.038.

关键词: unidirectional solidification;pore-size;hydroxyapatite;replacement;cartilage;porosity;matrix