F.T.Cheng
材料科学技术（英文）
The present communication addresses an interesting problem related to the indeterminacy in hardness of superelastic NiTi reported by Xu et al. The origin of the indeterminacy is attributed to the inadequacy of the conventional Vickers hardness testing measurement which does not record elastic deformation, and thus the indeterminacy may be removed with suitable techniques. Concepts of hardness in relation to deformation are clarified. Recommendations for measuring the hardness of NiTi and other elastic-plastic materials are suggested, together with comments on the advantages and disadvantages of each of these methods.
关键词:
Hardness
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null
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null
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null
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null
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Jingpei XIE
,
Yaomin ZHU
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Xiaoping WANG
材料科学技术（英文）
The M-s temperature, Delta G(gamma-->alpha), Delta G(gamma-->M) and mechanical energy under a non-severe impact loading in a medium manganese steel (Fe-7Mn-1.2C) have been calculated by means of Xu's Fe-X-C model. The relation between the yield strength of austenite and the driving force for martensite transformation has been established. It is proved that the martensite transformation can take place in a medium manganese steel (Fe-7Mn-1.2C alloy) under a non-severe impact loading.
关键词:
李莉
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李庆芬
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郑磊
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徐庭栋
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杜善义
钢铁研究学报
以工业用12Cr1MoV钢为研究对象,通过俄歇电子能谱分析方法(AES),对磷在恒温过程中的非平衡晶界偏聚浓度进行了测定.获得的磷在钢中的非平衡晶界偏聚动力学曲线直接验证了非平衡晶界偏聚动力学理论中的Xu-Song模型.
关键词:
晶界偏聚
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临界时间
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扩散
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钢
Journal of Physics-Condensed Matter
This research purposes to investigate the atomic and electronic structures of the Al/TiC(001) interface with lattice misfit using the ab initio pseudopotential approach. A detailed analysis of the relaxed atomic structure reveals that the atoms over the initial unfavourable sites relax to the favourable sites along the lateral plane. The properties of the semicoherent interface can be taken as averages over the different coherent sites. In addition, the interface atoms in relatively favourable regions are dragged near to the interface, while those in unfavourable regions are pushed away from the interface. Therefore, a large war-ping near the interface is made perpendicular to the lateral plane. The calculated adhesions explain the different wetting results from the viewpoint of structural transition. The subsequent analysis of electronic properties demonstrates that adhesions dominate mainly via the strong Al-C covalent bond.
关键词:
first-principles;1st principles;adhesion;surfaces;misfit;1st-principles;wettability;al
X. Q. Yang
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L. X. Huo
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Y. F. Zhang and J. X. Yan (School of Material Science and Engineering
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Tianjin University
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Tianjin 300072
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China)
金属学报(英文版)
The buckling formation and influence factors during welding thin - plated structures were investigated based on finite element methods, An engineering treatment method for prdicating the buckling distor- tion was proposed in here. It was used the equivalent applied thermal - load to simulate the welding residual stress,therefore the calculation of complex welding distoriton can be transformed into 3D elas- tic structural applied- load analyses, which can reduce the quantities of calculating works effectively. The validation of the method was verified by comparison of the numerical simulation and experimental results. The simulation of buckling distorition for side - walled structrues of paseenger train was per- formed and the calculation was in agreement with measuring results in general. It was shown that the main factors for producing the buckling were the intermittent fillet and ping the during welding the stiffened beams and columns to the panel.The existence of the free edge of panels would reduce the crit- ical buckling stress and enlarge the deflection obviously,but the continuous weld in closed frames didn' t degrade the buckling situation.
关键词:
welding buckling distortion
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陆樟献
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龚雁
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王渊明
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王正才
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陈善飞
功能材料与器件学报
doi:10.3969/j.issn.1007-4252.2012.01.005
基于Xu等人的经典振荡磁偶极子模型和Matsumoto等人给出的双折射驰豫理论,研究了磁致双折射和二向色性对磁性液体薄片的光透射率弛豫特性的影响.理论推导了磁性液体的双折射和二向色性函数的偏振光透射率具体表达式,并进行了数值模拟计算.该问题的研究对磁性液体光学各向异性的深入认识以及相关磁性液体光学器件的应用具有一定的指导意义.
关键词:
物理光学
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双折射驰豫
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二向色性驰豫
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磁性液体
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磁偶极子
Z.L. Ding
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Y.C. Fan
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H.B. Qi
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D.L. Ren
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J.B. Guo and Z.Q. Jiang Shijiazhuang Railway Institute
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Shijiazhuang 050043
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China
金属学报(英文版)
The SiC_p/Al-alloy composite front broke rotors designed for SHANGHAI SANTANA cars were prepared by semi-solid stirring+liquid for ping process. The properties of the composite rotors were examined. The composite brake rotors were subjected to dynamometer tests on a SCHENCK broke testing system, referring to TLll0 standard of VOLKSWAGEN Company. The friction coefficient and thermal response during fade testing and the wear performance of the composite rotors were studied as the function of various parameters, such as braking pressures, initial speeds, initial temperatures, torque and decelerations, and compared with that of conventional cast iron rotors. The results showed that the properties of SiC_p,/Al-alloy composite rotors can achieve the requirements of commercial cast iron rotor.s. The results also suggested that the friction coefficients of composite rotors under different broking conditions are within the deviation band specified by the TLll0 standard, and the temperature rise of the composite rotors at the cud of each fade stop is lower than that of the cast iron rotors. The wear resistance of composite rotors was higher than that of cast iron rotors. The friction and wear mechanism are analyzed.
关键词:
SiC_p/Al-alloy composite
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