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INVESTIGATION OF BEHAVIOUR OF B IN Ni_3Al ALLOYS BY POSITRON ANNIHILATION TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 1993年第2期6卷 125-128页

作者： DENG Wen XIONG Liangyue LONG Qiwei international centre for materials physics Institute of Metal Research,Academia Sinica,shenyang,chinaWANG Shuhe GUO Jianting Institute of Metal Research,Academia Sinica,shenyang,china Institute of Metal Research,Academia Sinica,shenyang 110015,china Inst of Metal Research Acad Sinica Shenyang China

The behuviour of B atoms added to mono-and poly-crystalline Ni_3AI alloys has been investi- gated hy positron annihilation technique(PA T).If the additive of B was less than 1.37 at-%, some of B atoms solid-solutioned interstitially into matrix and distorted the lattice,thus the lifetime (τ) of positron (e^+) Or matrix dilated:the others of them segregated on vacancy-like defects and formed "filling effect",thus the mean lifetime (τ)and S parameters *** B added was increased up to 2.22 at-%,more defects having larger free volume were induced by horide eutectic occurred along grain boundaries and grain interior,thus the τ in vacancy-like defects.τ and S parameters increased remarkably.

关键词： Ni_3Al positron annihilation B additive defect

Ni-based Ni-Fe-B-Si-Ta bulk metallic glasses

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 440-444页

作者： ZHU ChunLei1, WANG Qing1, ZHAO YaJun1, WANG YingMin1, QIANG JianBing1 & DONG Chuang1,21 Key Lab of materials Modification (Ministry of Education), School of materials Science and Engineering, Dalian University of Technology, Dalian 116024, china 2 international Center for materials physics, chinese academy of sciences, shenyang 110016, china 1. Key Lab of materials Modification (Ministry of Education) School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China2. International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

The glass-forming ability and properties of Ni-based Ni-Fe-B-Si-Ta bulk metallic glasses are explored in this work. The alloy compositions are determined by using a combination of the cluster line approach, the multi-alloying strategy and the substitutions of similar elements. Bulk metallic glasses with diameters of 3 mm take shape at compositions formulated under the clus- ter-plus-glue-atom model [M9B]B~[(Ni1-xFex)7.71(Si0.66Ta0.34)1.29B]B0.94=(Ni1-xFex)70.5B17.7Si7.8Ta4, x=0.35–0.45, where the bracketed part is the cluster and the unbracketed part is the glue atoms. These alloys exhibit good magnetic properties. The maximum Is is found in the (Ni0.55Fe0.45)70.5B17.7Si7.8Ta4 alloy which reaches 0.51 T, with its Hc as low as 8.5 A/m. Interestingly, these alloys display dual glass transitions at (Ni0.65Fe0.35)70.5B17.7Si7.8Ta4, (Ni0.60Fe0.4)70.5B17.7Si7.8Ta4 and (Ni0.55Fe0.45)70.5B17.7- Si7.8Ta4 as unveiled by Temperature-Modulated Differential Scanning Calorimetry.

关键词： bulk metallic glasses cluster Ni-Fe-based alloys Modulated Differential Scanning Calorimetry

Biomimetic Design and Test of Composite materials

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Journal of materials Science & Technology 1993年第1期9卷 9-19页

作者： Benlian ZHOU international centre for materials physics,Institute of Metal Research,Academia Sinica,shenyang,110015,china

A series of superior properties will make composites the most important structural materials in the next *** they are difficult to design owing to the complexity of structure and processing. Biomaterials had been naturally selected and evolved for millions of years,a great variety of their ra- tional composite structures could be taken as our reference in the biomimetic design of composite *** are many difficult problems in the current study on composite materials such as: brittleness of continuous fibers and difficulties in interface design;easy pull-out of short fibers from matrix causing failure in reinforcing;being less easy in selecting the aspect ratio of whiskers and dif- ficulties in finding the way of toughening composites of ceramic matrices as well as the way of heal- ing inner *** describing the distinct composite features,the functional adaptability and self-healing ability of biomaterials,several examples o.f biomimetic design of composite materials have been listed in this paper:the optimum design of composites simulating bamboo structure;the fine structure of bamboo fibers;the dumb-bell model simulating animal bone;the model on the pull-out of fiber with fractal-tree structure and some tentative works on the healing of inner damage in composite materials The methodology of biomimetic design and its future have been given at the ast part of this paper.

关键词： composite material biomimetic fiber

Enhanced Bamboo Reinforced Aluminum Laminates

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Journal of materials Science & Technology 1994年第5期10卷 355-358页

作者： Shihong LI Shaoyun FU and Benlian ZHOU (Int. centre for Mater. Phys., Institute of Metal Research, chinese academy of Science, shenyang, 110015, china)Qiyun ZENG and Xianrong BAO (Institute of Applied Ecology, chinese academy of sciences, shenyang, 11 Inst of Metal Research Shenyang China

A new technique has been developed for flattening circular natural bamboo culm to plate form for remarkably enhancing its mechanical properties, The enhanced bamboo, cheaper than Al, is then used to reinforce an aluminum alloy for civilian applications. The properties of the composite are greatly enhanced compared to those of the Al alloy. The Al protects bamboo from bioerosion and improves hygroscopicity

关键词： Laminated composites

Laser-induced Chemical VaporDeposited Nanosized Silicon Nitridewith Double Optical Beams

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chinese Journal of Lasers 1996年第1期B5卷 67-71页

作者： WANG Weixiang (Institute of Quantum Electronices, South china Normal Unicersity, Guangzhou 510631, china international centre for materials physics, Academia Sinica, shenyang, 110015, china)LIU Songhao(Institute of Quantum Electronices, South china Normal South china Normal Univ Guangzhou China

It was studied that how the CO2laser lines affect the characteristics of silicon nitride powders synthesized by laser-induced chemical vapor deposition （LICVD）. A new method was proposed for nanosized silicon nitride synthesis, and it is called double optical beam LICVD. The stoichiometric silicon nitride nanopowders with high purity were produced by using this new method. The ratio of N/Si of the powder is as high as 1. 321 which is very close to the ideal value of 1. 333.

关键词： laser-induced chemical vapor deposition nanosized silicon nitride

Solitary Magnon Localization in Antiferromagnet RbFeBr_3

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Journal of materials Science & Technology 1994年第3期10卷 225-228页

作者： Wuming LIU and Benlian ZHOU(international centre for materials physics, Institute of Metal Research, Academia Sinica, shenyang, 110015, china)Liming GUO(Dept. of Mathematics, Institute of Yunnan Nationality, Xunming, 650031, china) Inst of Metal Research Academia Sinica Shenyang China

Introducing the Dyson-Maleev transformation. the coherent state ansatz and the time-dependent variation principle, we obtain two partial different equations of motion from Hamiltonian. Employing the method of multiple scales. we reduce these equations into the envelope function equations and force the amplitude function to satisfy a nonlinear Schrodinger equation. Using the inverse- scat-tering transformation, we obtain the single soliton solution and discuss the solitary magnon localization in antiferromagnet RbFeBr3

关键词： Rev Solitary Magnon Localization in Antiferromagnet RbFeBr3

A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation

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Journal of materials Science & Technology 1999年第5期15卷 435-438页

作者： Qiang LI and Yongbo XU(State Key Laboratory for Fatigue and Fracture of materials, Institute of Metal Research, chinese academy of sciences,shenyang 110015, china) To whom correspondence should be addressed Present address: Analysis Cener, School of Mater State Key Laboratory for Fatigue and Fracture of materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China Analysis Cener School of Materials Tianjin University Tianjin 300072 China international Center of materials physics Chinese Academy of Sciences Shenyang 110015 China Laboratory for Non-linear Mechanics of Continuous Media Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Recrystallized grains, less than 200 nm in diameter were observed in heavily shear zones of a high strength low alloy steel and a Ni-based alloy, and Also grain refinement, less than 3 μm in diameter was made in high purity aluminum by ECAE at ambient temperature. The experimental results showed that high strain rate and large deformation could induce dynamic *** on dislocation dynamics and grain orientation change enhanced by plastic deformation,a model for the recrystallization process is developed. The model is used to explain the ultra fine grains which are formed at a temperature still much lower than that for the conventional recrystallization

关键词： Figure A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation

Microstructure characterization of high-energy product Nd-Fe-B thin film

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Progress in Natural Science:materials international 2010年第01期20卷 76-80页

作者： Fang XU~1,Fang YANG~2,Xian-ping DONG~1,Lan-ting ZHANG~1,Wei LIU~2,Zhi-dong ZHANG~2 1.School of materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,china 2.shenyang National Laboratory for materials Science,Institute of Metal Research and international centre for materials physics,chinese academy of sciences,shenyang 110016,china [a] School of materials Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China [b] shenyang National Laboratory for materials Science Institute of Metal Research and International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

A Si/Mo（50 nm）/Nd-Fe-B（400 nm）/Mo（50 nm）film with relatively high-energy product（BH）max=247 kJ/m3)was prepared on a Si substrate heated at 650℃.The microstructure of the film was investigated by X-ray diffractometry（XRD）and high-resolution transmission electron microscopy（HRTEM）.The Nd-Fe-B thin film shows a notable out-of-plane c-axis *** （110）orientated Mo grains is proved to promote the growth of c-axis oriented texture of the Nd2Fe14B grains,which is favorable to achieve a high ***-scale spherical Nd-O phases composed of randomly orientated polycrystalline grains and a sharp grain boundary without grain boundary phase between two Nd2Fe14B grains are *** coercivity highly depends on a certain amount of Nd-O phase and interface morphology.

关键词： Nd-Fe-B thin films microstructure Nd-O phase magnetic properties

High-pressure synthesis and properties of CeO_2-ZrO_2 solid solution

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chinese Science Bulletin 2001年第10期46卷 801-806页

作者： XU Dapeng, WANG Quanyong, LU Zhe, LIU Zhiguo, ZHANG Gongmu & SU Wenhui1. Department of physics, Jilin University, Changchun 130023 china 2. international Center for materials physics, chinese academy of sciences, shenyang 110015, china 3. Center for Condensed Matter and Radiation physics, china Center of Advanced Science and Technology (World Laboratory), Beijing 100080, china Department of physics Jilin University Changchun China international Center for materials physics Chinese Academy of Sciences Shenyang China Center for Condensed Matter and Radiation physics China Center of Advanced Science and Technology (World Laboratory) Beijing China

Using nanoparticles of CeO2 and ZrO2 prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2 solid solution (c-Ce0.5Z0.5O2) has been synthesized under 3.1 GPa at 1073 K for the first time. The structure of the c-Ce0.5Zr0.5O2 has not been changed before and after annealing at 773 K for 1 h. Only an unknown EPR signal (g =1.990) has been observed in the c-Ce0.5Zr0.5O2 and not varied after annealing at 773 K for 1 h, which exhibited that there exists no Ce3+ in the c-Ce0.5Zr0.5O2 and the Ce4+ has not been reduced into Ce3+ after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (a =1.2×10-5 S/cm at 823 K, σ=2.1 ×10-3 S/cm at 1123 K) is the same as that of CeO2, but smaller than that of Y2O3-stabilized ZrO2. A marked curvature at T = 823 K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 823 K is lower than that above 823 K, and the reason has been discussed.

关键词： CeO2-ZrO2 nanocrystalline high-pressure and -temperature solid-state reaction solid solution.