Kaifeng ZHANG
,
Wenbo HAN
,
Wei WU
,
Guofeng WANG
,
Dezhong WU
材料科学技术（英文）
The research on numerical simulation for combinative process of SPF/DB is carried out in this paper. The contacting problem of sheets is analyzed by using the penalty method. In order to solve the contact problem of different parts of the sheet, a new algorithm for contacting judgment is proposed. According to the relation of the distance vector and the vector of contacting element area, and the condition of contact, it can be judged whether or not a node on the slave surface and the corresponding master surface are in the state of SPF/DB. The Mindlin shell element is employed to simulate SPF/DB process of an asymmetry double-cell cup of Ti-6Al-4V to examine the efficiency of the new algorithm using ARVIP-3D. The results of the numerical simulation are in good agreement with experimental results.
关键词:
Numerical simulation
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null
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null
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Kaifeng ZHANG
,
Deliang YIN
,
Guofeng WANG
,
Wenbo HAN
材料科学技术（英文）
Superplasticity of AZ31 Mg alloy at the temperature range of 250~450℃ and stain rate range of 0.7×10-3~1.4×10-1 s-1 was examined through uniaxial tensile test. Optical microscopy (OM) and scanning electron microscopy (SEM) were employed to investigate the morphology of cavities and surface relief near fracture surface, respectively. It is shown that AZ31 Mg alloy starts to exhibit superplasticity from 300℃. The maximum elongation of 362.5% was obtained at 400℃ and strain rate of 0.7×10-3 s-1. There exist many O-shaped cavities and filaments at the boundaries near fracture surface. The fracture of filaments results in intergranular cavity and the model for the formation of intergranular cavities is proposed. The growth of cavities is plasticity-controlled and the serrated boundaries of intergranular cavities agree with the results of surface relieves.
关键词:
AZ31 magnesium alloy
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null
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null
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Journal of Materials Research
The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.
关键词:
room-temperature
Philosophical Magazine
The error of Equation (15b) in my article [Z.D. Zhang, Phil. Mag. 87 (2007) p.5309] in the application of the Jordan-Wigner transformation does not affect the validity of the putative exact solution, since the solution is not derived directly from that equation. Other objections of Perk's comment [J.H.H. Perk, Phil. Mag. 89 (2009) p.761] are the same as those in Wu et al.'s comments [F.Y. Wu et al., Phil. Mag. 88 (2008) p.3093; p.3103], which do not stand on solid ground and which I have sought to refute in my previous response [Z.D. Zhang, Phil. Mag. 88 (2008) p.3097]. The conjectured solution can be utilized to understand critical phenomena in various systems, whereas the conjectures are open to rigorous proof.
关键词:
3D Ising model;exact solution;conjecture;critical phenomena;ferromagnetism;magnetic phase transition;model;analyticity
中国腐蚀与防护学报
N。1Atmospheric Corrosivlty for Steels………………………………………………… .LIANG Caideng HO[I i。-tat（6）Caustic Stress Corrosion Cr。king of Alloy 800 Part 2.The Effect of Thiosul执e……………………………………… KONG De-sheng YANG Wu ZHAO Guo-zheng HUANG De.ltL。ZHANG Yu。。he CHEN She。g-bac（13）SERS slid E16CttOCh6iniC81 Stlldy Of Illhibit1Oli M6ch＆tllsth Of ThlollY68 Oil ITOll ID H....
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Physics Letters A
In a magnetic system, consistent with Griffiths analyticity requirements one can parameterize the equation of state near criticality by writing H = r(beta delta)h(theta), T = rt(theta) and the magnetization M = r(beta)m(theta), where T is measured from the critical temperature. For the insulating ferromagnet CrBr(3), the experimental data of Ho and Litster [J.T. Ho, J.D. Litster, Phys. Rev. Lett. 22 (1969) 6031 is well fitted by m(theta) as a linear function of theta [P. Schofield, J.D. Litster, J.T Ho, Phys. Rev. Lett. 23 (1969) 1098]. Also Ho and Litster give beta = 0.368, gamma = 1.215 and delta = 4.3. Those critical experiments are very close to the recent 31) king results of Zhang [Z.D. Zhang, Philos. Mag. 87 (2007) 5309], namely beta = 3/8, gamma = 5/4 and delta = 13/3. We therefore predict that m(theta) will be proportional to theta as a fingerprint of the 3D Ising Hamiltonian. (C) 2009 Elsevier B.V. All rights reserved.
关键词:
Critical-point effects;Critical exponents;Ising model;Criticality;Ferromagnet;Magnetic equation of state;critical exponents
