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81.
X.G.Zhou X.M.Zhao Y.B.Xu D.Wu 《金属学报(英文版)》2004,17(5):754-760
On the basis of phase transformation kinetics, the transformation of γ→α,P,B have been investigated through considering the effect of deformation. The calculation methods of volume fraction have also been given. Comparing with common method, the simulated results are in more agreement with experiment results. 相似文献
82.
T. Yang B.H. LiDepartment of Materials Physics University of Science Technology Beijing Beijing ChinaK. Kang T. SuzukiInformation Storage Materials Laboratory Toyota Technological Institute Nagoya - Japan 《金属学报(英文版)》2003,16(4):261-265
(FePt/Ag)n nano-multilayers were deposited on MgO (100) single crystal with laser ablation and then subjected to annealing. FePt L1o grains with (001) texture and thus a large perpendicular magnetic anisotropy constant Ku of the order of 106 J/m3 were formed. A thick Ag layer is found to be favorable for decreasing the dispersion of the easy axis for magnetization. The measurement of time decay of magnetization gave rise to a small activation volume of the order of 10-25m3, showing the promising of being the recording medium for future high density perpendicular recording. 相似文献
83.
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85.
Dongming Hu Radovan Kovacevic 《International Journal of Machine Tools and Manufacture》2003,43(1):419
Laser-Based Additive Manufacturing (LBAM) is a promising manufacturing technology that can be widely applied to part preparation, surface modification, and Solid Freeform Fabrication (SFF). A large number of parameters govern the LBAM process. These parameters are sensitive to the environmental variations, and they also influence each other. This paper introduces the research work in RCAM on improving the performance of the LBAM process. Metal powder delivery real-time sensing and control is studied to achieve a controllable powder delivery for fabrication of functionally graded material. A closed-loop control system based on infrared image sensing is built for control of the heat input and size of the molten pool in the LBAM process. The closed-loop control results show a great improvement in the geometrical accuracy of the built features. A three-dimensional finite element model is also established to explore the thermal behavior of the molten pool in the closed-loop controlled LBAM process. 相似文献
86.
The main aim of this work was to study the effects of particle size, particle volume fraction, and matrix strength on the
long fatigue crack growth resistance of two different grades of Al alloys (Al2124-T1 and Al6061-T1) reinforced with SiC particles.
Basically, it was found that an increase in particle volume fraction and particle size increases the fatigue crack growth
resistance at near threshold and Paris regimen, with matrix strength having a smaller effect. Near final failure, the stronger
and more brittle composites are affected more by static modes of failure as the applied maximum stress intensity factor (K
max) approaches mode I plane strain fracture toughness (K
IC). 相似文献
87.
Pil-Ryung Cha Ho-Seok Nam Dae-Yeong Jeon Jong-Kyu Yoon 《Metals and Materials International》2002,8(1):119-127
This study presents a simple and robust algorithm for the optimal design of the system with coupled complex transport phenomena:
the transport phenomena comprise fluid flow, heat and mass transfer. The (1+1)-Evolution Strategy method is adopted as the optimization method. In order to analyze the transport phenomena in the complex geometry generated
during the optimization procedure, thefinite volume method with a boundary fitted curvilinear coordinate system is used. To confirm the validity of the present method, the optimal
design for the inner shape of the simplified two-dimensionalSubmerged Entry Nozzle in the continuous slab caster is conducted. It is shown that the resulting design of the nozzle is consistent with the purpose
and constraints of the design. 相似文献
88.
89.
多元酚——甲醛树脂中游离酚,游离醛含量的测定 总被引:6,自引:0,他引:6
多元酚--甲醛树脂是本院开发的热固粘接剂新产品,本文给出了这一产品技术指标中游离酚、游离醛含量的测定方法,并对方法进行了讨论。 相似文献
90.