D. W Shi
,
J. Y Huang and Q. W Long(International Centre for Materials Physics
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
ChinaState Key Laboratory for Fatigue and Fracture of Materials
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China )
金属学报(英文版)
We proposed an equation of Langevin type to describe the interface evolution in crystals under nonequilibrium conditions(such as in Cu-Fe or Cu-Co system upon ball miling). The scaling property (H) of this equation is in good agreement with the Monte Carlo simulations decribed by Bellon and Averback. In this equation the volume dchsion and intedece diffusion are all important and this is consistent with some experimental results.
关键词:
scaling
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null
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null
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null
S.J. Zhao
,
Y.C. Wang
,
J.Q. You
,
Q.B. Yang
,
L.G. Zhou and H.Q. Ye (Department of Physics
,
Xiangtan University
,
Xiangtan 411105
,
China)(Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
The Chinese Academy of Sciences
,
Shenyang 110015
,
China)(Department of Materials Science
,
Northeastern University
,
Shenyang 110006
,
China)
金属学报(英文版)
A structural transition in the fcc ∑=5 (120)/[001] high-angle tilt grain-boundary(GB)is investigated by molecular-dynamics simulation. The calculations have been performed at various temperutures and the thermodynamic melting point Tm of the model system is determined by using a many-body potential fitted to copper. A thermal disorder transition in the GB region occurs well below the melting point. Our results indicate that such a transition is a continuous process and there is no evidence of premelting, which is entirely in accord with experiment results and theoretical prediction.Moreover we also observed that melting initiated at the interface and then propagated into the bulk quickly at or above Tm.
关键词:
moleculandynamics
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null
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null
WANG Bowen
,
WU Changheng
,
ZHUANG Yuzhi
,
JIN Ximei
,
LI Jingyuan(Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)(Shenyang Institute of Technology
,
Shenyang 110023
,
China)(Institute of Physics
,
Chinese Academy of Sciences
,
Beijing 100080
,
China)
金属学报(英文版)
The structure and magnetostriction of R(Fe_(1-x)Al_x)_y alloys(R=Dy_(0.65)Tb_(0.25)Pr_(0.1),x≤0.3,y=1.8 and 2) have been investigated using metallography, X-ray diffraction, electron probe micro- analysis(EPMA) and standard strain gauge techniques.It was found that the matrix of R(Fe_(1-x)Al_x)_2 alloys is cubic Laves phase(Dy,Tb,Pr)(Fe,Al)_2 and the second phase is PuNi3-type (Dy,Tb,Pr)(Fe,Al)_3 when x<0.15.The R(Fe_(1-x)Al_x)_(1.8) alloys contain trace of rare earth-rich phase.The magnetostriction of R(Fe_(1-x)Al_x)_y alloys decreases with increasing x in high magnetic fields; however, it exhibits a peak when x = 0.05 in low magnetic fields(H≤ 160 kA / m).The magnetostriction of R(Fe_(1-x)Al_x)_(1.8) alloys is higher than that of R(Fe_(1-x)Al_x)_2 alloys when x<0.15.
关键词:
:rare earth-iron alloy
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null
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null
R.M. Wang
,
C.Z. Li
,
S. W. Zhang and M.G.Yan(1)Institute of Aeronautical Materials
,
Beijing 100095
,
China 2)Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China 3)Beijing Laboratory of Electron Microscopy
,
Chinese Academy of Sciences
,
Beijing 100080
,
China Manuscript received 26 August 1996)
金属学报(英文版)
The microstructures of the grain boundary phases in Fe-Ni-Co-Nb-Ti superalloy have been studied by high resolution electron microscopy (HREM).Besides the Laves phase,three other grain boundary phases have been found and analyzed. The ε phase particles are needle-like with some stacking faults along the(0001) direction. The dominant phase at the grain boundaries is the orthorhombic phase that is also rod-like. High reselution image also confirms the existence of the triclinic phase at the grain boundaries that is irregular and scarce.
关键词:
:high resolution electron microscopy
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null
,
null
LIU Changqing
,
LI Meishuan
,
JIN Zhujing
,
WU Weitao Corrosion Science Laboratory
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
China research assistant
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The cantilever bending test,particularly monitored by an acoustic emission technique, was adopted to measure the tensile and interfacial adhesive strengths of the HCD ion plated fine TiN film on pure Ti substrate.The behaviors of film damaging were found to be characterized by:an internal tensile stress which exceeded its tensile strength for TiN facing upward,and a shearing stress along film substrate interface which exceeded its adhesive strength for TiN facing downward.The measured tensile and adhcsive strengths are 603 and 242 MPa respectively.
关键词:
tensile strength
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null
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null
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null
WANG Huaming Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaZHANG Qing Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
ChinaSHAO Hesheng Beijing Graduate School
,
China University of Mining and Technology
,
Beijing
,
China Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The role of austenite in impact-abrasion process was studied on the basis of the impact-abrasion test results of a newly developed austenite-bainitic ferrite dual-phase abrasion-resistant steel with high strength,high toughness and high strain-hardening ability. It is found that the morphology,distribution and mechanical stability,rather than the volume fraction,of austenite govern the impact abrasion behaviour.Only the appropriate amount of fine and evenly dispersed austenite with adequate mechanical stability in high strength matrices,contribute effectively to the irnpact-abrasion resistance of the materials.While large quantity of coarse austenite with poor mechanical stability,especially when it acted as a continuous matrix of the material,is extremely detrimental to impact-abrasion resistance.
关键词:
austenite
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null
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null
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null
LI Hiaogang
,
MENG Qinghai
,
CHEN Hua
,
CHEN Jinwei
,
YAO Zhiming
,
KE Wei(State Key Laboratory of Corrosion Science
,
Institute of Corrosion and Protection of Metals
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)(Fushun Petroleum Institute
,
Fushun 113001
,
China)
金属学报(英文版)
Hydrogen attack occurred in low carbon steel and steel 25CrMo which had been exposed in hydrogen under 18MPa at 450 and 500℃ for 240,480 and 720 h.The methane bubbles and microcracks grow along grain boundaries.The degree of hydrogen attack increases with increasing exposure time and temperature.Magnetic acoustic emission(MAE) was used to detect the degree of hydrogen attack.The results show that the characteristics of MAE for samples of low carbon steel and steel 15CrMo with hydrogen attack have changed obviously comparing to the samples without hydrogen attack,and the MAE signals was sensitive to the degree of hydrogen attack at the last stage of hydrogen attack.The magnetic detection way,as a new method of nonrestrictive testing of hydrogen attack,can be used to detect the hydrogen attack in practice.
关键词:
:magnetic acoustic emission
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null
,
null
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null
WU Lijun
,
ZHAO Lihua
,
YANG Qiaoqin
,
LI Shaolu
,
LI Xieqian(Materials Research and Test Centre
,
Hunan University
,
Changsha 410082
,
China)(Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)
金属学报(英文版)
The structure of Al-Mn-Zn-Mg alloy powder annealed at 800℃ has been studied by transmisston electron microscopy(TEM).An approximant phase(named as C-phase) to the decagonal phase was found and its crystal structure was determined It belongs to c-center orthorhombic lattice with a=2.35 nm,b=3.27 nm and c=1.22 nm.We stillfound a hexagonal phase with a=0.7) nm and c=0.79 nm,(named as phase) in the annealed alloy powder.The annealed alloy powder is composed of the C-phase,the phase,the decagonal phase and Al solid solution.
关键词:
:quasicrystal
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null
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null
SUN Xiukui CHEN Wenxiu XU Jian FAN Xueshu WEI Wenduo State Key Laboratory of Rapidly Solidified Non-Equilibrium Alloys
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaWU Yukun PENG Yingguo Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
China Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The crystal habit,crystalline structure,surface condition and composition of the ultrafine Al particles prepared by inert gas evaporation method were studied in detail by means of high resolution transmission electron microscope,X-ray diffraction and X-ray photo-electron spectrum.The results indicate that the ultrafine Al particles prepared in high pure inert gas are of clear crystal habits,single crystal in a large majority and fcc crystalline structure with a_0=0.405 nm.It is also found on the surface of the Al particles that there is a layer of amor- phous Al_2O_3 with 2 nm average thickness,which could protect the particles against oxidizing further.Therefore,the ultrafine Al particles prepared by the inert gas evaporation method are very stable in atmosphere.
关键词:
ultrafine Al particle
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null
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null
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null
XIA Yuebo ZHANG Tianyi State Key Laboratory for Fatigue and Fracture of Materials
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaFEI Guangtao ZHOU Xing Laboratory of Internal Friction and Defects in Solids
,
Institute of Solid State Physics
,
Academia Sinica
,
Hefei
,
China Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The variation of cyclic stress,internal friction and ultrasonic attenuation during cyclic deformation and relations among them have been investigated with different slip orientation Al single crystals.The results indicate that the value of cyclic stress σ,internal friction Q~(-1)and ultrasonic attenuation △α depend obviously on the slip orientation.There are large differences in above three parameters for different slip orientation Al crystals.In early stage of fatigue life,σ and △α increase and Q~(-1)decreases with cycles N,and △α reached maxi- mum before σ,while Q~(-1)and σ get the valley and the peak,respectively,at same cycles.
关键词:
crystal orientation
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null
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null
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null
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null
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null
