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粘结超磁致伸缩Tb-Dy-Fe合金磁致伸缩性能的研究

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中国稀土学报 2003年第6期21卷 729-732页

作者：王博文李淑英闫荣格曹淑英翁玲河北工业大学磁技术与磁材料研究中心天津工业大学理学院天津300160

采用粘结方法制备了Tb1-xDyxFe2.状合金样品,经筛选确定了粘结材料的制备工艺,测试了粘结棒状合金样品的静态、动态磁致伸缩系数和磁机械耦合系数k33。结果表明,所制备的粘结棒状样品具有较高的磁致伸缩性能,且动态磁致伸缩参数d33和... 详细信息

采用粘结方法制备了Tb1-xDyxFe2.状合金样品,经筛选确定了粘结材料的制备工艺,测试了粘结棒状合金样品的静态、动态磁致伸缩系数和磁机械耦合系数k33。结果表明,所制备的粘结棒状样品具有较高的磁致伸缩性能,且动态磁致伸缩参数d33和磁机械耦合系数k33高于国外所报道的结果。

关键词：金属材料磁性材料磁致伸缩性能粘结 Terfenol-D 稀土元素 Tb-Dy-Fe合金粘结磁体制备工艺

Unusual Behaviour of Dislocation Velocity Exponent in Dislocation Multiplication Model

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Journal of materials Science & Technology 1998年第3期14卷 215-218页

作者： Xaowei WANG(international Centre for materials {2., Institute of Metal Research, chinese academy of sciences,shenyang 110015, china) international Centre for materials {2. Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The chaotic behaviour of dislocation multiplication process was investigated. The change of Lyapunov exponent which is used to determine the stability of quasi-periodic and chaotic behavior as well as that of equilibrium points, and periodic solution was reported by using an iteration model of dislocation multiplication. An unusual behavior of Lyapunov exponent and Feigenbaum exponent which respond to the geometric convergence of orbit from bifurcation to chaos was shown by dislocation velocity exponent m and there is a distinction on the tendency of convergence for the dislocation multiplication model when it was compared with logistic map. It is reasonable for the difference to be analyzed from the materials viewpoint. (Edited author abstract) 9 Refs.

关键词： Unusual Behaviour of Dislocation Velocity Exponent in Dislocation Multiplication Model

Role of Edge and Screw Dislocations in Deformation of Metals

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Journal of materials Science & Technology 1995年第2期11卷 133-136页

作者： Chiwei LUNG(international Centre for materials {2., Institute of Metal Research,chinese academy of sciences, shenyang, 110015, china) Inst of Metal Research Shenyang China

It was widely accepted that the screw dislocation is responsible for the strong temperature dependence of the yield stresses observed in bcc metals. In this paper, we show the role of edge dislocations in the deformation of metals and point out that in some cases, its main contribution to the plastic flow behaviour cannot be ignored.

关键词： Crystal structure

Multirange Fractals in materials: Applications to Fracture and Mechanical Alloying under Ball Milling

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Journal of materials Science & Technology 1997年第4期13卷 255-259页

作者： Chiwei LUNG(international Centre for materials {2., Institute of Metal Research,chinese academy of sciences, shenyang 110015, china) international Centre for materials {2. Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A new model of multirange fractals is proposed to explain the experimental results observed on the fractal dimensions of the fractured surfaces in materials. A new explanation to the Williford's multifractal curve on the relationship of fractal dimension with fracture properties in materials has been given. It shows the importance of fractorizing out the effect of fractal structure from other physical causes and separating the appropriate range of scale from multirange fractals. Mechanical alloying process under ball milling as a non-equilibrium dynamical system has been also analyzed.

关键词： Ball Applications to Fracture and Mechanical Alloying under Ball Milling Multirange Fractals in materials

Effects of Positron Diffusion and Its Application in Composite System

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Journal of materials Science & Technology 2000年第3期16卷 311-314页

作者： Jian JIANG, Xinzhang ZHOU and ChiWei LUNG (international center for {2. physics, Institute of Metal Research, chinese academy of sciences, shenyang 110015, china) international center for {2. physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The effects of positron diffusion on the measured S parameter have been investigated by a point-source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the samples of a homogeneous semi-infinite medium and a film of definite thickness. Then the results are used to analyze the S parameters in several composite systems and interface models.

关键词： Effects of Positron Diffusion and Its Application in Composite System

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 Chuang1,2. Key Lab of materials Modification (Ministry of Education), School of materials Science and Engineering, Dalian University of Technology, Dalian 11602.,{2. 2.international center for materials physics, chinese academy of sciences, shenyang 110016,{2. Dalian University of Technology Key Lab of Materials Modification (Ministry of Education) School of Materials Science and Engineering Dalian China (GRID:grid.30055.33) (ISNI:***) Dalian University of Technology Key Lab of Materials Modification (Ministry of Education) School of Materials Science and Engineering Dalian China (GRID:grid.30055.33) (ISNI:***) chinese academy of {2. International Center for Materials Physics Shenyang China (GRID:grid.9227.e) (ISNI:***)

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)1.2.B]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

Dislocation Velocity Exponent and the Strain Rate

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Journal of materials Science & Technology 2001年第3期17卷 363-366页

作者： Hongyan LIU and Xiaowei WANG international center for Material {2., Institute of Metal Research, chinese academy of sciences, shenyang 110016, china E-mail: liu@*** Intl. Cent. for Mat. Phys. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The process of dislocation multiplication has been described hv chaos theory, trying to reveal the connection between the microstructures on the mesoscopic scale and the mechanical properties of material on the macroscopic scale. The relationship between the dislocation velocity exponent and the maximum of strain rate is given. The results obtained from logistic equation with exponent and the dislocation multiplication dynamic equation are compared. A scale law in one-dimension-map model with exponent is shown when the exponents of equations are changed.

关键词： Dislocation Velocity Exponent and the Strain Rate

Universality and Specificity of Fractal Dimension of Fractured Surfaces in materials

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Journal of materials Science & Technology 2000年第1期16卷 1-4页

作者： Chiwei LUNG and Shenggang WANG (international Centre for materials {2., Institute of Metal Research, chinese academy of sciences, shenyang 110015, china) international Centre for materials {2. Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

After calculation on the fracture angles under various conditions of specific surface energies with different symmetry operations of rotation, the complicated behavior of dependence of fractal dimension on the structure of crystal is shown. It is found that the crack propagates along the weakest crystal plane no matter what the direction of the maximum stress is if the anisotropy is sufficiently strong; and then, the fractal dimension of the fractured surfaces might be determined by the approximate fractal structure already existed in the material. Specificity of the fractal dimension of fractured surfaces would be easy to appear in this case. Reversely, the crack propagates along the direction of the maximum stress no matter what direction of the weakest crystal plane is if the anisotropy is sufficiently weak. Universality of the fractal dimension of fractured surfaces would be possible to appear in this case. In many real materials, universality and specificity of the materials are associated. The fractal dimension measured may more or less be influenced by the structure of materials and it shows its universality through the specificity of materials.

关键词： Universality and Specificity of Fractal Dimension of Fractured Surfaces in materials

Effects of Distribution of Induced Defects on Positron Diffusion

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Journal of materials Science & Technology 2000年第1期16卷 73-75页

作者： Xinzhang ZHOU, Jian JIANG and Chiwei LUNG (international center for {2. physics, Institute of Metal Research, chinese academy of sciences, shenyang 110015, china) international center for {2. physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The effects of distribution of induced defects on the positron diffusion was studied by using the point-source diffusion model and 6 function method.

关键词： Effects of Distribution of Induced Defects on Positron Diffusion