材料期刊网

Service Performance of Engineering Materials

Andrej Atrens

材料科学技术（英）

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

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

Department of Metallurgy and Materials Engineering of Chongqing University

YAN Guangting Chongqing University , Sichuan , China.

材料科学技术（英）

关键词:

3-{6-[(1R,2R,4S)-2-羟基-1,3,3-三甲基二环[2.2.1]庚烷-2-基]-吡啶-2-基}-2'-特戊酰基-1,1'-(R)-联萘-2,2'-酚合钼(Ⅵ)的合成、单晶结构及应用

马丽 , 何亚兵 , 金日哲 , 卞证 , 高连勋

应用化学 doi:10.3969/j.issn.1000-0518.2009.05.005

化合物3-{6-[(1R,2R,4S)-2-羟基-1,3,3-三甲基二环[2.2.1]庚烷-2-基]-吡啶-2-基}-1,1'-(R)-联萘-2,2'-酚(1)与特戊酰氯反应,得到单个羟基封端的化合物3-{6-[(1R,2R,4S)-2-羟基-1,3,3-三甲基二环[2.2.1]庚烷-2-基]-吡啶-2-基}-2'-特戊酰基-1,1'-(R)-联萘-2,2'-酚(2).化合物2与MoO2(acac)2进行配位得到金属配合物3-{6-[(1R,2R,4S)-2-羟基-1,3,3-三甲基二环[2.2.1]庚烷-2-基]-吡啶-2-基}-2'-特戊酰基-1,1'-(R)-联萘-2,2'-酚合钼(酰)[Mo(Ⅵ)-2],通过核磁共振氢谱、红外光谱和质谱测试技术对其结构进行了表征,用X射线单晶衍射测定了化合物的晶体结构.结果表明,化合物晶体属单斜晶系,空间群为P21,晶胞参数α=1.179 34(10)nm,b=2.304 5(2)nm,c=1.518 88(13)nm,α=90°,β=112.84°,γ=90°,V=3.804 2(6)nm3,Z=4,μ=0.392 mm-1,D=1.298 Mg/m3,F(000)=1 544,R1=0.077 5,wR2=0.193 4,GOF=1.122.在配合物中,钥原子处于六配位的八面体配位环境,配位原子分别来自1个分子水中的O原子、配体分子中1个酚羟基的O,吡啶环中的O,醇羟基中的O形成ONO三齿配合物.配合物Mo(Ⅵ)-2在萘乙烯的不对称环氧化反应中,得到中等活性和较低的对映选择性.

关键词: 吡啶醇基联萘酚 , 钼(Ⅵ)配合物 , 晶体结构 , 不对称催化

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

[R1R3IM]+[BF4]-离子液体中链状纳米金的制备

李中春 , 顾爱军 , 周全法

稀有金属材料与工程

以N-甲基咪唑和溴代正丁烷为起始原料,采用两步法合成了1-丁基-3-甲基咪唑四氟硼酸盐离子液体,并对所合成的离子液体做了红外光谱表征.在1-丁基-3-甲基咪唑四氟硼酸盐离子液体中,利用硼氢化钠还原氯金酸,制备了纳米金.紫外-可见光谱和透射电镜(TEM)试验结果表明,所制备的纳米金以链状为主.离子液体在纳米金制备过程中不仅起到了溶剂作用,还起到了修饰剂的作用.

关键词: 离子液体 , 纳米金 , 制备

(R)-1-(4-苄氧基-3-硝基苯基)-2-溴乙醇制备工艺的改进

张宝华 , 史兰香

应用化学 doi:10.3724/SP.J.1095.2013.30005

以4-苄氧基-3-硝基-α-溴代苯乙酮为原料,在聚苯乙烯磺酰胺化固载的(R)-二苯基脯氨醇形成的(口恶)唑硼烷催化下,经NaBH4/Me3SiCl不对称还原制得了(R,R)-福莫特罗的关键中间体(R)-1-(4-苄氧基-3-硝基苯基)-2-溴乙醇,收率95％,ee值95.4％.手性氨基醇可以方便的分离和回收利用,降低了生产成本.用NaBH4/Me3SiCl为还原剂代替BH3,降低了毒性,提高了安全性.

关键词: (R)-(苄氧基-硝基苯基)-溴乙醇 , NaBH4/Me3SiCl , 不对称还原 , 固载(R)-二苯基脯氨醇

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

CoxR1-xAl2O4(R=Zn,Mg)钴蓝颜料反射性能的研究

闫国杰 , 程继健 , 张金朝 , 春胜利

无机材料学报 doi:10.3321/j.issn:1000-324X.2000.04.015

采用化学共沉淀法成功地制备出适用于彩电显象管内荧光体着色的CoxR1-xAl2O4(R=Zn、Mg，x=0.8~1.0)钴蓝颜料：450nm波长处反射率最大提高18.2%，600nm处反射率最大降低5%.通过对该颜料反射率的影响因素,如掺杂离子类型、掺杂浓度和Co2+离子浓度的探讨，结论如下：Zn2+、Mg2+改变钴蓝颜料反射性能的作用机理为晶格畸变引起Co2+3d轨道电子能级分裂程度的变化；对于掺杂离子Zn2+、Mg2+，x下限值分别约为0.85和0.8.

关键词: CoxR1-xAl2O4颜料 , 反射性能 , 掺杂离子

Evaluation of mechanical properties of structural materials by a spherical indentation based on the representative strain-an improved algorithm at great depth ratio

金属学报(英文版)

At great depth ratio, two methodologies based on the representative strain were improved to extract mechanical properties of metallic engineering structural materials from P-h curve of an indentation response. The improved aspects include: the combination of great ratio h(1)/R=0.1 and h(2)/R=0.4 replaced h(1)/R=0.01 and h(2)/R=0.06 (Cao's method) and h(1)/R=0.1 and h(2)/R=0.3 (Ogasawara's method); three types of metallic engineering structural materials with obviously different elastic modulus were dealt with to get their calculation parameters, respectively; a new parameter reflecting the effect of work-hardening exponent n was introduced to get the dimensionless function which is independent of n and a relationship between W/(h(3)sigma(r)S) and E*/(sigma(r)S) at great depth ratio. By using the results of finite element simulation, the efficiency and accuracy of the improved method have been proved, and it showed that the accuracy of the improved method is much better than the former method.

关键词: Spherical indentation;Representative strain;Metallic engineering;structural material;Mechanical property;Great depth ratio;measuring elastoplastic properties;energy-based method;plastic;properties;conical indentation;metal materials;hardness definitions;bulk materials;extract;tests