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Chinese Science Bulletin 2002年第1期47卷 85-88页

作者： PAN Xuemin & BIAN Xiufangkey laboratory of Liquid Structure and Heredity of materials, Education Ministry, shandong university, Ji’nan 250061, china key laboratory of Liquid Structure Education Ministry Shandong University Ji'nan 250061 China

Liquid structure of molten pure Cu, Cu-12Al, Cu-12Al-4Ni (mass fraction, %) alloys has been investigated using the X-ray diffraction method. It is found that the main peak of the structure factor of pure Cu is symmetrical. In the front of main peak, the curve takes on a shape of parabola, whereas a distinct pre-peak has been found around a scattering vector magnitude of 18.5 nm-1 in the structure factor of the liquid Cu-12Al alloy. This pre-peak increases its inten-sity with the addition of Ni in the liquid Cu-12Al-4Ni alloy. The appearance of a pre-peak is a mark of the mediate-range order. Based on Daken-Gurry theory and according to mu-tual interaction between unlike atoms, the analysis of corre-lation between different composition and liquid structure was done: the strong interaction exists between Cu and Ni, so Cu-Al can form strong chemical bond which causes compound-forming behavior. Therefore, the medium-range size clusters can form in melt. The presence of the pre-peak corresponds to these

关键词： Cu-12Al-4Ni alloy liquid structure shape memory alloy X-ray diffraction.

Effects of Heat Treatment Temperature and Time on Structure and Static Magnetic Property of W-type Ferrite Hollow Microspheres

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Journal of Wuhan university of Technology(materials Science) 2007年第1期22卷 168-170页

作者：任平 Energy Source and Environmental Engineering Department Shanghai University of Electric Power

Hollow spheres of hexagonal ferrite BaCozFelrO27 were fabricated through a spray pyrolysis technique using co-precipitation ferrite powder precursor as materials, followed by calcinations in an air atmosphere. The phase composition, micro-morphology, and static magnetic property of the particles were measured by XRD, SEM, and VSM. The results indicate that the method for preparation of ferrite hollow microspheres （FHM） results in a broad particles size distribution. The density of FHM decreased from 5.31 g/ cm^3 to 2.31 g/cm^3. When the heating rate was 5℃/min, and temperature was 1 200℃ for 4 hours, pure W-type ferrites were formed. With the heat treatment temperature and time increasing, the crystal structure becomes perfect, the saturation magnetization is increased and the coercive force is decreased.

关键词： microwave absorber ferrite hollow microspheres spray pyrolysis

STUDY OF Ag DIFFUSION INTO Cu SINGLE crystalS BY RUTHERFORD BACKSCATTERING SPECTROMETRY

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 332-334页

作者： R.Wang 1) key laboratory of Beam Technology and materials Modification, Ministry of Education, Beijing 100875, china2) institute of Low Energy Nuclear Physics, Beijing Normal university, Beijing 100875, china3) Beijing Radiation Center, Beijing 100875, china key laboratory of Beam Technology and materials Modification Ministry of Education Beijing 100875China institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China

4.0Me V 7Li++ RBS was used for investigations of thermal diffusion of Ag in Cu single crystals. The annealing of samples was carried out in vacuum in the temperature range from 498K to 613K. The element depth concentration profiles transformed from RBS spectra indicate that the diffusion of Ag into Cu is a typical volume diffusion. The Arrhenius parameters corresponding to the diffusion were obtained.

关键词： Ag diffusion single crystal

Structure correlation of Co_(79.5)Sn_(20.5) eutectic alloy between liquid and solid states

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Science china(Technological Sciences) 2009年第12期52卷 3674-3677页

作者： SUN JianJun 1,2 ,ZHENG HongLiang 1 ,SHI XinYing 1 &TIAN XueLei 1 1key laboratory for Liquid-Solid Structural Evolution and Processing of materials(Ministry of Education),shandong university, jinan 250061,china 2shandong Labour Vocation and Technology College,jinan 250022,china 1. key laboratory for Liquid-Solid Structural Evolution and Processing of materials (Ministry of Education) Shandong University Jinan 250061 China 2. shandong Labour Vocation and Technology College Jinan 250022 China

The liquid structure of Co79.5Sn20.5 eutectic alloy has been investigated by means of X-ray diffraction. The result shows that the liquid structure of Co79.5Sn20.5 alloy displays quite stable from 1350℃ to 1150℃ although the short-range order increases with temperature *** addition,the correlation between the liquid structure and solid structure also has been analyzed by"the nanocrystal model".It is shown that the melt of Co79.5Sn20.5 alloy consists ofβCo3Sn2 clusters andβCo clusters, indicating that the liquid structure and solid structure of Co79.5Sn20.5 eutectic alloy are strikingly similar.

关键词： liquid structure X-ray diffraction nanocrystal model liquid-solid correlation undercooling

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Characterizing modified surface layer of 316L stainless steel treated by high current pulsed electron beam

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Rare Metals 2007年第S1期26卷 61-66页

作者： GROSDIDIER Thierry state key laboratory for materials Modification Dalian University of Technology

High current pulsed electron beam(HCPEB) is now developing as a useful tool for surface modification of *** concentrated electron flux transferring its energy into the surface layer of target material within a short pulse time,coupled thermal and stress processes would lead to the formation of metastalbe microstructure with improved *** the present work,HCPEB treatment of 316L stainless steel(SS) was carried out and the microstructural changes in modified surface layer were characterized with optical microscopy,X-ray diffractometry and electron backscatter diffractometry(EBSD) *** corrosion resistance of modified surface was measured in a 5wt.% salt *** evolution regularity of surface craters and grain refinement effect,as well as the preferred orientation of(111) crystal plane occurring in the HCPEB treatment under different working parameters were discussed along with their influence on corrosion resistance.

关键词： high current pulsed electron beam surface modification 316L stainless steel microstructure corrosion

Effects of Scale Composition on Oxidation Kinetics of Fe-based Superalloy

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Journal of Wuhan university of Technology(materials Science) 2010年第1期25卷 99-103页

作者：王海涛于化顺 key laboratory for Liquid Structure and Heredity of materials of Education Ministry School of Materials Science and EngineeringShandong University

By oxidation weight gain method, four groups of Fe-based superalloys with different content of chromium, aluminium and silicon were tested at 1 200 ℃ for 500 hours. According to the oxidation weight gains, the oxidation kinetic curves were plotted, and the equations were regressed by least square method and non-linear curve fitting. The effects of different scale compositions on the morphology and oxidation kinetic law were studied further by analysis of X-ray diffraction （XRD） and scanning electron microscope （SEM）. It is found that the compounded scale is composed of Cr2O3, Al2O3, SiO2 and FeCr2O4, with compact structure and fine grains, possessing complete oxidation resistance at 1 200 ℃, and the oxidation kinetic curve follows the power function of y=axb （a0, 0b1）. When the compounded scale lacks Al2O3 or SiO2, it becomes weak in oxidation resistance, but the oxidation kinetic curve still follows the power function with bigger parameter b. When Cr2O3 is absent, the kinetic curve shows two parts： the slow adding of oxidation weight gains at the beginning and the ascending line in the end. Such scale loses oxidation resistance completely.

关键词： superalloy iron alloy oxide scale oxidation resistance property

Generation and controlling of the dispersive wave by femtosecond pulses propagating in the normal dispersion regimes of the birefringent photonic crystal fiber

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 643-648页

作者： LI ShuGuang1,2, ZHENG Yi1, YIN GuoBing2, ZHANG Lei2, ZHOU GuiYao2 & HOU LanTian2 1 School of Science, Beijing Jiaotong university, Beijing 100044, china 2 key laboratory of Metastable materials Science and Technology, College of Science, Yanshan university, Qinhuangdao 066004, china 1. School of Science Beijing Jiaotong University Beijing 100044 China2. Key Laboratory of Metastable Materials Science and Technology College of Science Yanshan University Qinhuangdao 066004 China

This paper studies the generation of the dispersive wave (DW) in the normal dispersion regimes of the birefringent photonic crystal fiber (BPCF) fabricated in this work. The remarkable blue-shifted radiation is found to be generated when 30 fs pulses are input in the normal dispersion regime of the BPCF for the first time. The characteristics of the blue-shifted DW strongly depend on the polarization of the input pulse. As a result, two peaks appear in the blue-shifted region of the spectrum when the input pulses polarize along the slow axis of the BPCF. With the increase of the center wavelength of the initial input pulse, the difference between the wavelengths of the two peaks widens. The peak location in the spectrum can be explained by the phase matching condition between the DW and the input pulse. In addition, when the input polarization is set to an angle of 45° with respect to the principal axes of the BPCF, the cross-phase modulation and coherent coupling between two orthogonally polarized modes would result in pulse trapping in the BPCF. Accordingly, the DW shift toward short wavelength is restrained. The DW generation in the normal-dispersion regimes of BPCF can be controlled by the phase matching condition and polarization of the input pulse.

关键词： birefringent photonic crystal fiber normal dispersion dispersive wave pulse trapping

Preparation of Nanosized AlOOH and Its Application in Polymer-inorganic Nanocomposites

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Journal of Wuhan university of Technology(materials Science) 2008年第5期23卷 638-643页

作者：廖海达 state key Lab of Advanced Technology for materials Synthesis and Processing Wuhan University of Technology College of Chemistry and Ecological Engineering Guangxi University for Nationalities key Lab of Nonferrous materials and New Processing Technology (Guangxi university Guilin University of Technology) Ministry of Education

With industrial grade Al（OH）3 as raw materials, the self dispersion nanosized AlOOH crystal powder were prepared by the sol-hydrothermal method. The results of XRD and TEM show that the nanosized AlOOH could automatically disperse to a single-dispersing state in water without surface modification, dispersant, additive and accessional conditions （ultrasonic wave dispersing, ball-mill dispersing）. The application results of the product indicate that the nanosized AlOOH can be composed into a toughened nanocomposites without surface modification. Accordingly, the self dispersion characteristic and mechanism of hydrothermal crystallization and charging composite dispersion of nanosized AIOOH are found, and a new technique of preparing polymer/inorganic nanocomposites is proposed, which is called blending compositing new techniques of sol even dispersing at auasi-homogeneous phase.

关键词： self dispersion nanosized AlOOH peptizing-hydrothermal method nanocomposites

Size and distribution of Te inclusions in detector-grade CdZnTe ingots

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Progress in Natural Science:materials International 2011年第1期21卷 66-72页

作者： Ya-dong XU~(1,2),Wan-qi JIE~1,Yi-hui HE~1,Rong-rong GUO~1,Tao WANG~1,Gang-qiang ZHA~1 1.state key laboratory of Solidification Processing,Northwestern Polytechnical university,Xi'an 710072,china 2.School of materials Science and Engineering,Northwestern Polytechnical university,Xi'an 710072,china [a] state key laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 China [b] School of materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

To observe the Te inclusions distribution along the axial direction of CdZnTe ingots,batches of as-grown detector-grade CdZnTe crystals grown by vertical Bridgman method,were investigated using IR transmission ***,there is not a rigorous regularity for the micron-scale Te inclusions distribution along the axial direction of CdZnTe ingots according to the measurements of the present *** size and distribution variations of Te inclusions are attributed to the growth velocity, furnace temperature situation and morphological changes at the liquid-solid interface during crystal *** mobility lifetime products were discussed in conjunction with Te ***,no strict correlations are identified between the sizes and concentrations of Te inclusions and theγ-ray spectroscopy *** defects in CdZnTe crystals,which are not visible via IR transmission imaging,potentially attribute to CdZnTe detectors performance degrades.

关键词： CdZnTe Te inclusions IR imaging crystallization interface