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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 25-36页

作者： Jue zhu Longyuan LI Ningtao zhu zhejiang Provincial Engineering Research Center for the Safety of Pressure Vessel and Pipeline Key Laboratory of Impact and Safety Engineering (Ningbo University) Ministry of Education School of Engineering Computing and Mathematics University of Plymouth Xi'an zhanshi Testing & Engineering Co.Ltd.

Carbon nanotubes(CNTs) have garnered great attention in recent years due to their outstanding electrical, thermal, and mechanical properties. The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity. This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect. In this modified Maxwell model, the CNTs-filled polymer composite is modeled as a three-phase composite, consisting of a matrix(polymer), inclusions(CNTs), and a transition zone(tunneling zone). The effective electrical conductivity(EEC) of the composite is calculated based on the volume fractions and electrical conductivities of the matrix, inclusions, and transition zone. The model's validity is confirmed through the use of available test data, which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites. This study offers valuable insights into the design of high-performance conductive polymer nanocomposites, and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.

关键词： Nanoclay

MATRIX INVESTIGATION ON ISAICHEV ORIENTATION RELATIONSHIP

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Acta Metallurgica Sinica(English Letters) 1999年第2期12卷 185-190页

作者： Sheng, z.q. Xiao, H. Nuclear Power Inst of China Chengdu China

By means of TEM technique the orientation relationships of cementite, precipitated from islands of granular bainite during tempering, with ferrite have been observed. By calculating the eigenvalues and eigenvectors of transformation matrix, Isaichev relationship has been analyzed. The results indicate that Isaichev relationship is indeed the sum of Kurdjumov-Sachs relationship and Pitsch relationship, so the viewpoint that the cementite with Isaichev relationship precipitates from austenite, instead of ferrite, was confirmed. Moreover, the matrix calculation shows that three reported orientation relationships among austenite, ferrite and cementite in pearlitic transformation cannot be simultaneously valid. (Edited author abstract) 4 Refs.

关键词： Carbides Crystal orientation Eigenvalues and eigenfunctions Nuclear reactors Pearlitic transformations Phase transitions

FEM SIMULATION OF RESIDUAL STRESSES INDUCED BY LASER SHOCK WITH OVERLAPPING LASER SPOTS

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Acta Metallurgica Sinica(English Letters) 2008年第2期21卷 125-132页

作者： Y.X. Hu z.q. Yao State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong University Shanghai 200240China

The finite element method is presented to attain the numerical simulation of the residual stresses field in the material treated by laser shock processing. The distribution of residual stresses generated by a single laser shock with square and round laser spot is predicted and validated by experimental results. With the Finite Element Method （FEM） model, effects of different overlapping rates and impact sequences on the distribution of residual stresses are simulated. The results indicate that：（1） Overlapping laser shock can increase the compressive residual stresses. However, it is not effective on the growth of plastically affected depth; （2） Overlapping rate should be optimized and selected carefully for the large area treatment. Appropriate overlapping rate is beneficial to obtain a homogeneous residual stress field; （3） The impact sequence has a great effect on the residual stress field. It can greatly attenuate the phenomenon of the “residual stress hole” to obtain a homogeneous residual stress field.

关键词： Laser shock processing Overlapping Residual stress Finite element method

Stamping Robust Design Method and Its Application

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上海交通大学学报 2004年第Z2期38卷 161-165页

作者： z.q. Lin Jian Ai Weigang zhang Shuhui Li School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China Baoshan Iron&Steel Co. ltd Baoshan Shanghai China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China

The application of the robust design to stamping is discussed in the paper. The regression equation of the quality index and its influencing factors can be attained by using method of central composite design. Stamping computer simulation takes the place of real stamping experiments to fulfill the special experimental conditions. The real stamping experiments prove the correctness and the feasibility of the stamping robust design method-central composite design.

关键词： robust design central composite design computer simulation integrated quality index

First-principles Investigation of Bi Segregation at the Solder Interface of Cu/Cu_3Sn(010)

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Journal of Materials Science & Technology 2010年第12期26卷 1057-1062页

作者： X.Y. Pang z.q. Liu S.q. Wang J.K. Shang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign IL 61801 USA

Density functional theory was employed to investigate the bismuth segregation at Cu/Cu3Sn（010） interface. Five initial constructions were introduced by adopting the adhesion energy criterion. Among them, the so-called ＂between-Cu＂ construction in which the interface Cu atoms of Cu slab locate along Cu-Cu bond direction in Cu3Sn slab was found to be the most energy-favored at an adhesion energy of 1.96 J/m^2. Based on this construction, five possible segregation sites were examined, and the most likely segregation site was determined with adhesion energy as low as 1.06 J/m^2, which was almost half of the initial one. Comparing with other sitest adhesion energies, it was concluded that size effect took a large part in embrittlement. The analyses of atomic structure and electronic density revealed that the slabs shifted away from interfaces due to bismuth segregation, and the atoms around Bi atom were Dressed away. This calculated work agreed aualitativelv with reported experimental results.

关键词： First-principles calculation Segregation Bismuth Interface SnBi solder

Tizr-base Bulk Metallic Glass with over 50 mm in Diameter

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Journal of Materials Science & Technology 2010年第6期26卷 481-486页

作者： M. q. Tang H.F. zhang z. W. zhu H.M. Fu A.M. Wang H. Li z.q. Hu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72Wenhua Road Shenyang 110016 China

Low-cost Tizr-base bulk metallic glasses （BMGs）（Ti36.1zr33.2Ni5.8Be24.9）100-xCux （x=5, 7 and g） with a maximum size of over 50 mm in diameter were developed by optimizing the alloy composition. The idea is initiated by selecting a particular microstructure comprising primary β-Ti dendrite and amorphous phase. Afterwards, based on this composition of amorphous phase, a class of Tizr-base bulk metallic glasses was designed step by step to reach the optimum composition range. The glass transition temperature （Tg）, initial crystallization temperature （Tx） and width of supercooled region （AT） of （***33.2Nis.8Be24.9）91Cu9 BMG are 611, 055 and 44 K, respectively. The （Ti36.1zr33.2Ni5.8Be24.9）91Cu9 BMG exhibits low density of 5.541 g·cm-3 and high compressive fracture strength of 1800 MPa, which promises the potential application as structural materials.

关键词： Tizr-base alloy Bulk metallic glass (BMG) Fracture strength

STUDY ON TEMPERATURE FIELD INDUCED IN HIGH FREqUENCY INDUCTION HEATING

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 190-196页

作者： H. Shen z.q. Yao Y.J. Shi J. Hu School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China

A mathematical model was established for the temperature field developed during high frequency induction heating （HFIH） by Maxwell＇s equations. It required solving the coupled equations of the electromagnetic and temperature fields. The numerical simudation was performed using FEMLAB. The comparison of the calculations using the proposed model with experimental results showed a very good correlation. The effects of the heating parameters in high frequency induction such as the distance between the plate and the coil, the applied current, the frequency, and the turns of the coil on the temperature profiles developed in the plate were also discussed using the established model.

关键词： high frequency induction temperature field numerical simudation

NUMERICAL INVESTIGATION OF STRAIGHT-LINE LASER FORMING UNDER THE TEMPERATURE GRADIENT MECHANISM

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 144-150页

作者： Y.J. Shi H. Shen z.q. Yao J. Hu School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China

Laser forraing is a new flexible and dieless forming technique. To achieve the high accuracy forming, the temperature gradient mechanism （TGM） is studied. In the analysis of TGM, the plate bends about x-axis and about y-axis as well. To understand the deformation trend, the numerical simulation of deformation of plate is conducted by choosing different laser powers, laser spot diameters, scanning speeds, lengths, widths and thicknesses. From the results of simulation, it can be seen that the laser spot diameter, the scanning speed, laser power and thickness of plate play dominant roles in the laser forming process. However, the bending angles αx and αy show different trends with the variation of parameters. In addition, in comparison with above four parameters, the effect of length and width of plate on the beading angle may be neglected, but their effects are significant for the bending radius R.

关键词： laser forming temperature gradient mechanism metal plate

Synthesis and Characterization of Fe_(50)Cr_(14)Mo_(14)C_(14)B_6Gd_2 Bulk Amorphous Steel

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Journal of Materials Science & Technology 2010年第9期26卷 783-786页

作者： M. Iqbal J.I. Akhter H.F. zhang z.q. Hu Physics Division Pakistan Institute of Nuclear Science &: Technology P.O. Nilore Islamabad Pakistan Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Bulk amorphous steel having 7 mm thickness was synthesized to evaluate its thermal stability and mechanical *** steel was synthesized by Cu mold casting technique using 1-2N pure *** of the material was done by X-ray diffraction,differential scanning calorimetry and scanning electron *** activation energies were calculated by Kissinger equation and it was found that the steel had better stability against *** properties like Vicker s hardness,nanohardness,elastic modulus and elastic recovery of as-cast and annealed samples were *** was concluded that the present steel had good glass-forming ability（GFA） and mechanical properties.

关键词： Bulk amorphous steels Activation energy Glass-forming ability Mechanical properties