材料期刊网

EFFECT OF MAGNETIC FIELD ON MARTENSITIC TRANSFORMATION IN Fe-21Ni-4Mn ALLOY

SUN Enxi Dalian Railway College , Dalian , ChinaYANG Dazhi Dalian University of Technology , Dalian , ChinaXU Zuyao (T.Y.Hsu) Shanghai Jiaotong University , Shanghai , ChinaYANG Fuming ZHAO Ruwen Institute of Physics , Academia Sinica , Beijing , China YANG Dazhi , Professor , Dalian University of Technology , Dalian 116024 , China

金属学报(英文版)

The pulsed magnetic field induced martensitic transformation with isothermal and athermal kinetics in Fe-2Ni-4Mn(wt-%)alloy has been studied by means of magnetization measurements,optical microscopy and thermodymical analyses.It is shown that there exits a critical magnetic intensity for induing martensitic transformation at a given temperature above Ms.The critical magnetic field increases linearly with increasing ΔT= T-M_S.The magnetic field strongly promotes the athermal martensitic transforamtion and restrains the isothermal one.The entropy change ΔS for athermal transformation at Ms is 4.13 J/mol· K.The effect of magnetic field on martensitic transformation in Fe-21Ni-4Mn alloy is main- ly due to Zeeman effect.Lath,plate and butterfly martensities were observed under magnetic field.

关键词: magnetic field-induced martensitic transformation , null , null

Reheating Austenitizing Temperature of Spring Steel 60Si2MnA for Railway

CUI Juan , LIU Yazheng , PAN Hui , GAO Lifeng

钢铁研究学报(英文版)

The microsturctural transformation of austenite grain, pearlite interlamellar spacing, and lamellar cementite thickness of spring steel 60Si2MnA for railway were studied in the hotrolled and reheated states. Furthermore, the effect of microstructural characterization on its final mechanical properties was discussed. The results showed that as far as 60Si2MnA, the pearlite interlamellar spacing determined the hardness, whereas, the austenite grain determined the toughness. Compared with microstructure and mechanical properties in the hotrolled state, after reheating treatment at 950 ℃, its average grain sizes are apparently fine and the pearlite interlamellar spacing and lamellar cementite thickness coarsen to some extent, but both hardness and impact toughness increase to HRC 48 and 85 J, respectively. In the course of making spring, the optimum reheating austenitizing temperature for the 60Si2MnA steel is 950 ℃.

关键词: austenitizing temperature;austenite grain;pearlite interlamellar spacing;hardness;toughness

钛等金属的SUN-Z-R复合技术

吴全兴

钛工业进展 doi:10.3969/j.issn.1009-9964.2001.02.008

关键词:

Experiment and Simulation of Metal Flow in Multi-stage Forming Process of Railway Wheel

Xiao-hui SHEN , Wei CHEN , Jun YAN , Lei ZHANG , Jing ZHANG

钢铁研究

关键词:

Reheating Austenitizing Temperature of Spring Steel 60Si2MnA for Railway

钢铁研究学报(英文版)

关键词:

Austenite Grain Size Evolution in Railway Wheel During Multi-Stage Forging Processes

钢铁研究学报(英文版)

关键词:

WELDING BETWEEN HIGH MANGANESE STEEL AND HIGH CARBON STEEL

M. H. Guo , D. C. Shao , Z. G Dong and J. C Yang National Key Laboratory Advanced Welding Production Technology , Harbin institute of Technology , Harbin 150001 , China

金属学报(英文版)

Manuscript received 30 July 1999 Abstract The shielded metal arc welding (SMAW) of a manganese steel part as a crossing of railway track to a carbon steel part as the rails of the railroad is the welding of dissimilar steel. It are was known that it is not possible to the the rail of railroad directly to the cross- ing of railway track made from a steel containing about 14% of manganese (wt. ) because of so many differences between the two kinds of steels such as composition, microstructure,mechanical properties and weldability.A method was used to solve the problem by presetting an intermediate layer on each side of the joint and other special procedures were used.The result of test indicated that a good weld joint was obtained.

关键词: high manganese steel , null , null , null

Influence of Inclusion on Crack Initiation in Wheel Rim

MI Guofa , NAN Hongyan , LIU Yanlei , ZHANG Bin , ZHANG Hong , SONG Guoxiang

钢铁研究学报(英文版)

Speed increase and heavy-haul of the railway freight car are the effective measures to raise the transport ability of railway, and they have been the new trend for railway freight car development. The increase of speed and axle load will lead to the increase of wheel-rail contact stress, which will make a great change of stress distribution in the whole wheel rim. Goodier equation was employed to analyze the stress state around inclusion and cavity. In the operation of wheel-rail contact stress, stress concentration occurred in the pole of Al2O3 spherical inclusion, while it appeared on the equator of cavity. The critical inclusion sizes of 25t axle load freight car wheel at different velocities, a certain distance away from the tread, were calculated by Murakami equation. By contrast the inclusion state in cast-steel wheel and rolled-steel wheel, the inclusion character in cast-steel wheel determined that it has much more excellent crack resistance than that of rolled-steel wheel. In the meantime, in order to reduce the probability of rim crack, some suggestions were put forward.

关键词: heavy-haul;contact stress;critical inclusion size;rim crack

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

CFRP双剪单钉连接接头强度分析

崔海涛 , 温卫东

宇航材料工艺 doi:10.3969/j.issn.1007-2330.2004.04.011

双剪连接接头是复合材料结构连接设计的主要环节.针对T300/KH304复合材料层合板的双剪连接形式,分析了单钉连接情况下的接头强度,并采用Yamada-Sun准则预测了该层合板结构双剪连接接头的破坏载荷.结果表明:该接头的破坏模式主要呈现为挤压破坏;Yamada-Sun准则可以较好地预测该结构的破坏载荷;所预测的接头的破坏载荷及破坏模式,试验结果与数值分析结果比较一致.

关键词: 复合材料层合板 , 双剪连接接头 , 强度分析 , 有限元法