材料期刊网

Corrosion of Y, Fe and Fe-15Y in H_2-H_2S Mixture under 10~(-3) Pa S_2 at 600～800℃

Yan NIU , Weitao WU and Chaoliu ZENG (State Key Lab. for Corrosion and Protection , Institute of Corrosion and Protection of Metals , Chinese Academy of Sciences , Shenyang 110015 , China)F. Gesmundo and F. Viani (Instituto di Chimica , Facolta di Ingegneria , Un

材料科学技术（英文）

The corrosion of an Fe-based alloy containing 15 wt pct Y in H2-H2S mixtures under 10-3 Pa S2 was studied at 600~800℃ in an attempt to find materials with improved sulphidation resistance with respect to pure Fe. The presence of Y has been shown to be beneflcial, but not sufficient to the level expected. In fact, the alloy is able to form at all tested temperatures an external FeS layer, beneath which a zone containing a mixture of the two sulphides is also present. Thus,Fe can still diffuse through this region to form the outer FeS layer with non-negligible rate. The corrosion rate of Fe is considerably reduced by the Y addition. but the alloy corrodes still much more rapidly than Y. The sulphidation kinetics is generally rather irregular for both the pure metals, while the corrosion rate of the alloy decreases with time and tends to become parabolic after an initial period of 12~17 h. The sulphidation behaviour of the alloys is discussed by taking into account the presence of an intermetallic compound Fe17Y2 and the limited solubility of Y in Fe

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膨胀型阻燃剂聚丙烯阻燃复合材料的研究

戴培邦

绝缘材料 doi:10.3969/j.issn.1009-9239.2008.06.005

采用乳液共混法制备了三聚氰胺/多聚磷酸铵/季戊四醇磷酸酯改性膨胀型阻燃剂(Mo-IFR),用双螺杆挤出机将Mo-IFR和未改性的三聚氰胺/多聚磷酸铵/季戊四醇磷酸酯膨胀型阻燃剂(Un-IFR)分别与聚丙烯(PP)共混制备了PP/Mo-IFR和PP/Un-IFR阻燃复合材料,研究了PP/Un-IFR与PP/Mo-IFR的力学性能、结晶性能和断面形貌.结果表明,随着阻燃剂用量的增加,PP/Mo-IFR与PP/Un-IFR的缺口冲击强度和拉伸强度下降,弯曲强度提高;但是,PP/Mo-IFR缺口冲击强度和拉伸强度的下降幅度比PP/Un-IFR的缺口冲击强度和拉伸强度的下降幅度要小得多,而PP/Mo-IFR的弯曲强度提高的幅度比PP/Un-IFR的弯曲强度提高的幅度大.PP/Un-IFR的冲击断面显示是脆性断裂,而PP/Mo-IFR的冲击断面显示是韧性断裂.X射线衍射显示Mo-IFR加入PP中,对PP的结晶性能没有显著的影响,IFR与PP的相容性良好.

关键词: 聚丙烯 , 膨胀型阻燃剂 , 力学性能 , 结晶

On the ferrite refinement during the dynamic strain-induced transformation: A cellular automaton modeling

Scripta Materialia

Two-dimensional cellular automaton modeling has been performed to investigate the mechanism of ferrite refinement during the dynamic strain-induced transformation (DSIT) from austenite (gamma) to ferrite (alpha) in a low-carbon steel. The simulated results indicate that the refinement of ferrite grains derived from the DSIT could be interpreted in context of "un-saturated" nucleation and limited growth. (c) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

关键词: dynamic strain-induced transformation;refined ferrite grains;low-carbon steel;cellular automaton model;ultrafine ferrite;carbon-steel;cooling rate;austenite;kinetics;growth

SUPERPLASTIC DEFORMATION BEHAVIOR OF SUPERHARD Al ALLOY LC4

JIANG Xinggang WU Qingling CUI Jianzhong MA Longxiang Northeast University of Technology , Shenyang , China

金属学报(英文版)

The superplasticity of high strength superhard A1 alloy LC4 was improved to a great extent by modified thermomechanical treatment.Its maximum elongation may be up to 2100% un- der deformation at initial strain rate of 8.33×10~(-4) S~(-1) at 510℃.Observations of the microstructure changes revealed that with the increase of the deformation,the grain grows and the alloy exhibits strain hardening.The excellent elongation of the alloy seems due to the in- crease of grain stability under deformation.

关键词: superplasticity , null , null , null

APPLICATION OF LEAD AS WATER SEALING MATERIAL IN UNDERGROUD MINE

J. Y. Xu1) and T. A. Diany2)1) Central Engineering & Research Institute for Non - Ferrous Metallurgical Industries , Beijing 100088 , China2) Chambishi Copper Mine , Za mbia

金属学报(英文版)

The application of lead as tem porary w ater - sealing m aterial for the stan dpipes in under ground mine is reported . It is considered that lead is a good w ater - sealing m aterial in un derground mine , especially for irregular opening with high - pressure rushing w ater . Leadseal is cheap , easy to use and less har m ful to w orkers an d environ m ent and m ay have widerapplication .

关键词: w ater sealing m aterial , null , null

INTERNAL FRICTION OF GRAIN BOUNDARIES IN Fe-P AND Fe-P-La ALLOYS CONTAINING TRACE Cu

JI Jingwen WEI Quanjin GENG Dianqi WU Yuqin Northeast University of Technology , Shenyang , China Professor , Dept.of Physics , Northeast University of Technology , Shenyang 110006 , China

金属学报(英文版)

The grain boundary internal friction(GBIF)in Fe-P and Fe-P-La alloys containing trace Cu has been studied.It is found that an addition of 0.584—0.722 wt-% La obviously reduces the IF,shifts grain boundary peaks towards higher temperatures,and produces a small addi- tional peak at even higher temperature.The mechanism of GBIF is explained as the movement of defects of atomic size,namely point defects,at gram boundaries and/or their clusters un- der stress.

关键词: internal friction , null , null , null , null

EFFECT OF RESIDUAL STRESS ON THE MARTENSITIC TRANSFORMATION OF SPUTTER-DEPOSITED SMA THIN FILMS

L. Wang , D. Xu , B.C. Cai

金属学报(英文版)

TiNi thin films were sputter-deposited on circular single-crystal silicon substrates un-der various sputtering parameters. The crystal structure and residual stress of the as-deposited films were determined by X-ray diffraction and substrate-curvature method.The phenomenon of stress-suppressed martensitic transformation was observed. It isconsidered that the residual stresses in SMA thin films based on circular substratesact as balanced biaxial tensile stresses. The status of equilibrant delays the align-ment of self-accommodated variants and the volume shrinkage during the martensitictransformation.

关键词: martensitic transformation , null , null

Preparation of AI-Ca Master Alloy by Electrolysis of Chloride-Fluoride Melts

QIU Zhuxian SU Quanqing ** Dept.of Nonferrous Metals , Northeast University of Technology , Shenyang , 110O06 , China+ To whom correspondence should be addressed

材料科学技术（英文）

Al-Ca master alloy was prepared in a labora- tory electrolysis cell.The operating parameters used were:temperature range 680-720℃,cathodic cur- rent density 0.76-1.10 A/cm~2,bath composition in wt-% 75-85 CaCl_2+2-5 KCl+2-5 CaF_2.Un- der optimal conditions the current efficiency reached 70-80% and the Ca-content 10-14 wt-%.

关键词: AI-Ca master alloy , null

INFLUENCE OF ZIRCONIUM ON MICROSTRUCTURE AND DAMPING CAPACITY OF ZA27 ALLOY

J.C. Wang , Z.M. Zhang , Y.L. Lu , G.S. Song and G.C. Yang (State Key Laboratory of Solidification Processing , Northwestern Polytechnical University , Xi'an 710072 , China)

金属学报(英文版)

To improve the damping capacities of metals and alloys, the microstructures and damping capacities of ZA27 alloy modified by Zr were studied, and the damping capacities at room tempemture were measured by using cantilever beam techniques. The experiment results show that Zr can refine the Al-rich primary phase and improve the damping Capacities saliently. Compared with the un-modified one, the damping capacity of ZA27 alloy modified by 0.3wt%Zr received 90 percent increment. The high damping capacities are attributed primarily to grain ablement and the increasing of phase interfaces.

关键词: ZA27 alloy , null , null , null

SYNTHESIS AND SOLID STATE SINTERING OF W-Ni-Fe NANO-COMPOSITE POWDERS

X.H.Qu , J.L. Fan , Y.M. Li and B. Y Huang(The State Key Laboratory for Powder Metallurgy , Central South University of Technology , Changsha410083 , China)

金属学报(英文版)

The mixture of 90%W 7wt%Ni and 3wt%Fe elemental powders was milled in a planetary high-enerpy ball mill. The evolution of the structure during milling and the sintering behavior Of the milled powders were tested. The results showed that by mechanical alloying W(Ni, Fe) supersatumted solid solution with nano-meter size formed, which can enhance the sintering process. Ftilly dense alloy from the milled powders was obtained through solid state sintering. The tensile strength of the obtained alloy is over 900MPa which is comparuble to that of the alloy sintered by traditional liquid-phase sintering from un-milled powders of the same composition.

关键词: mechanical alloying , null , null , null