材料期刊网

EFFECT OF AUSTENITIZING TEMPERATURE ON STRUCTURE AND MECHANICAL PROPERTIES OF 23NiCo ALLOY

P. Zhong , B. Ling and B. Z. Gu Beijing Institute of Aeronautical Materials , Beijing 100095 , China

金属学报(英文版)

Effectof the austenitizing temperature on the microstructure, strength, and toughness of23 NiCo alloy wasstudied . With increasing theaustenitizingtemperature,the reductionsin strength and hardness are probably caused by the coarsening of M2 Ccarbides. The use of higheraustenitizingtemperatureresultedinimproved impacttoughness duetothe dissolutionof undissolved,( CrFeMo)23 C6 carbides. For austenitizingtemperaturesgreaterthan 950 ℃ resultedinthelossofimpacttoughness. Astheaustenitizingtemperatureisincreasedto1050 ℃impacttoughnesslevelsarereduced on an averageby53 J/cm2 .Examination ofthefrac turesurfaceofimpacttoughnessspecimens viascanningelectron microscopy ( SEM) revealedthataustenitizing at1050 ℃and aged at482℃wasintergranularfracture .It wassuggested thatthisgrain boundary embrittlement wastheresultofthe formation of cementite particlesduring aging.

关键词: secondary hardening , null , null

EFFECT OF AN ELASTIC-PLASTIC SHOCK-WAVE .B. ON THE FATIGUE CRACK-GROWTH RATE OF WELDED-JOINTS

Fatigue & Fracture of Engineering Materials & Structures

Fatigue crack growth behavior in welded joints subjected to elastic-plastic shock waves was investigated using three-point-bend specimens. The results indicate that the fatigue crack growth rate is reduced in the affected region of elastic or plastic waves. The travel of a plastic stress wave reaches 10 to 13 mm depth, but the hardness in this region is not increased although the lattice distortion is high. The crack path morphologies were observed, and reasons for a decrease in crack growth rate are presented.

关键词:

Preparation of Li-B alloy and study of its microstructure and discharge characteristics

Zhijian LIU , Zhiyou LI , Wei DUAN , Xuanhui QU , Baiyun HUANG , Siqi ZHANG

材料科学技术（英文）

A LI-B alloy has been prepared using a pretreated amorphous B powder and pure Li ingot as starting materials by continually slow addition of B powder and intensified stirring in the process of melting. The microstructure and the discharge characteristic of the materials have been investigated. Results show that the problem of temperature control in synthesis would be modified by means of continual addition of B powder, the Li7B6 would be more finery distributed in the metal Li by means of intensified stirring. The discharge characteristic of the Li-B alloy using amorphous B as starting materials is almost the same with that of using crystalline B.

关键词:

阿莫西林对B-Z振荡反应的影响及其振荡指纹图谱

赖红伟 , 曹宏梅 , 董顺福 , 韩丽琴 , 陆钊 , 董树国 , 贾骐羽

应用化学 doi:10.3724/SP.J.1095.2014.30321

研究了阿莫西林对B-Z振荡反应的影响,结果表明,阿莫西林的加入明显地改变了振荡体系的周期和振幅,即对振荡体系产生扰动,且阿莫西林的浓度分别在1.5×10-5～2.4×10-3mol/L和4.7 × 10-5～4.8×10-3 mol/L范围内与振荡周期改变值Δt和振幅改变值ΔA均呈良好的线性关系,相关系数分别为0.9822和0.9846,同时结合FKN机理,初步探讨了阿莫西林扰动B-Z振荡反应的机理.

关键词: 阿莫西林 , 化学振荡 , 指纹图谱 , B-Z振荡

Fluence Dependence of Mean Sputter Depth for Bombarded Pt-Cu and ~(10)B-~(11)B Binary Materials

Liping ZHENG(Shanghai Institute of Nuclear Research , Chinese Academy of Sciences , Shanghai 201800 , China)(To whom correspondence should be addressed)Risheng LI(Laboratory of Atomic Imaging of Solids , Institute of Metal Research , Chinese Academy of Sciences

材料科学技术（英文）

The mean sputter depth depends on the surface composition gradient during ion implantation.For the high fluence ion implantation into a Pt-Cu alloy, the surface composition gradient of Cu is so large that the difference in mean sputter depth between Pt and Cu, is significant. However, for the high fluence ion implantation into 10B-11B isotope mixture, the surface composition gradient of 10B is so small that the difference in mean sputter depth between 10B and 11B is insignificant.

关键词:

FLUENCE DEPENDENCE OF MEAN SPUTTER DEPTH FOR BOMBARDED PT-CU AND B-10-B-11 BINARY MATERIALS

材料科学技术（英文）

The mean sputter depth depends on the surface composition gradient during ion implantation. For the high fluence ion implantation into a Pt-Cu alloy, the surface composition gradient of Cu is so large that the difference in mean sputter depth between Pt and Cu, is significant. However, for the high fluence ion implantation into B-10-B-11 isotope mixture, the surface composition gradient of B-10 is so small that the difference in mean sputter depth between B-10 and B-11 is insignificant.

关键词: monte-carlo simulation;elements

Catalysis on nano-carbon materials: Going where to? Preface

Catalysis Today

This contribution to the special issue of Catalysis Today is dedicated to selected contributions presented at the Carbocat-IV (Carbon for Catalysis) Symposium held in Dalian (China) on November 7-10 (2010). The introduction first shortly overviews the main reasons for the interest on carbon materials for catalysis and the elements of novelty discussed on the contributions of this issue, and then provide a concise outline of the general trends and developments in this field to give a glimpse on the progresses in the field, and on the perspectives of this exciting area of catalysis. (C) 2012 Elsevier B. V. All rights reserved.

关键词: Nano-carbon;Catalysis on carbon;Nanostructured carbon-based materials;Carbon hierarchy;ordered mesoporous carbon;metal-free;nanostructured carbon;activated;carbon;oxidative dehydrogenation;heterogeneous catalysis;sustainable;energy;counter electrode;porous carbons;fuel-cells

Image analysis of periodic rain accelerated corrosion of aeronautical aluminium alloys

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

Periodic rain tests have been carried out for simulating atmospheric corrosion of aeronautical aluminium alloys. A digital image preprocessing and analysis method based on wavelet transformation was used to study the corrosion morphology of aluminium alloys samples, through which an image feature parameter 8 was extracted and discussed. The influences of orthogonal experiment parameters on acceleration were analyzed according to image feature parameter 6 with analysis of variance (ANOVA) method, and the optimal parameters for accelerated corrosion test were also obtained. The result was shown to be consistent with that from weight loss method. (c) 2007 Elsevier B.V. All rights reserved.

关键词: aeronautical aluminium alloys;accelerated corrosion;linage analysis;simulated environment;atmospheric corrosion;electrochemical impedance;pitting corrosion;exposure;steel;zinc

Enhanced remanence and high product energy of Fe3B-based nanocrystalline magnetic materials

Nanostructured Materials

This paper presents new results of an investigation of a commercial rapidly quenched Nd4.5Fe77B18.5 alloy that was studied previously. The enhanced remanence Jr = 13.2 KGs and high product energy (BH)max = 16.2 MGOe are shown to be due to ultrafine grain. The microstructure, consisting of no alpha-Fe that results in optimum magnetic properties, occurs in the amorphous Nd4.5Fe77B18.5 alloy after crystallization. The coexistence of Fe3B, Nd2Fe14B and residual amorphous phase play dominant roles in the achievement of the hard magnetic properties, and hence, the amorphous phase seems to act as an effective magnetic exchange-coupled medium.

关键词: alloys

Interfacial characteristics of molten Bi-43Sn alloy on amorphous and crystalline Fe(78)B(13)Si(9)

Materials Letters

Interfacial characteristics of molten Bi-43Sn alloy on amorphous and crystalline Fe(78)B(13)Si(9) during wetting were investigated at 523 K, 573 K, 623 K and 673 K. It is found that an intertnetallic compound exists at the interface of Bi-43Sn alloy on amorphous FC(78)B(13)Si(9), while no intermediate reaction layer is formed at the interface of Bi-43Sn alloy on crystalline Fe(78)B(13)Si(9). For Bi-43Sn alloy/amorphous Fe(78)B(13)Si(9) system, isothermal aging was performed at 323 K, 373 K and 423 K. The layer growth of the intermetallic compound is mainly controlled by a diffusion-controlled mechanism in the temperature range studied because the values of time exponent (n) is approximately equal to 0.5. (c) 2007 Elsevier B. V. All rights reserved.

关键词: intermetallic compound;amorphous;crystalline;kinetic;diffusion;glass;cu