LIU Zhiguo CHEN Yong CAO Yanni Nanjing University
,
Nanjing
,
ChinaZHU Zhengsheng Shaanxi Iron and Steel Institute
,
Xi'an
,
China Professor
,
Dept.of Physics
,
Nanjing
,
University
,
Nanjing 210008
,
China
金属学报(英文版)
The microstructural evolution and precipitation hardening of an Elinvar alloy doped with Ti and Al during isothermal aging at 700℃ have been investigated by atom probe field ion microscopy and microhardness measurements.The γ′ precipiates are spherical and coherent with the matrix.The chemical composition of the precipitates are(Ni_(0.53)Fe_(0.47)_3 (Ti_(0.(?))Al_(0.4)). During aging,a Lifshitz-Wagner type dissolution and coarsening reaction of the precipitates has been observed,The hardness of the material varies with the aging time and reaches maxi- mum when the average diameter of the precipitates was about 11 nm.
关键词:
Elinvar alloy
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LIU Yihua Shandong University
,
Jinan
,
ChinaYA NG Linqian Huaqiao University
,
Quanzhou
,
Fujian
,
China LIU Yihua Associate Professor
,
Dept.of Physics
,
Shandong University
,
Jinan 250100
,
China
金属学报(英文版)
The amorphous CoZr soft magnetic films with superior properties were prepared by radio-frequency sputtering under pressure of 0.5Pa Ar.The saturation magnetization of the amorphous CoZr films with relation to the Zr content and temperature was investigated.The amorphous CoZr films composed of different constituents obey the Bloch T~(3/2)-low in a wide range of temperatures.The number of electrons transferred from each Zr atom to 3d energy band of Co calculated by the rigid band model is about 2.27.
关键词:
amorphous alloy
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LIN Guangming HUANG Yuanshi ZHANG Jinxiu Zhongshan University
,
Guangzhou
,
China LIN Guangming
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Associate Professor
,
Dept.of Physics
,
Zhongshan University
,
Guangzhou 510275
,
China
金属学报(英文版)
The snap-acting transition and two way shape memory (TWSM) effect have been obtained in a TWSM spring made of Ni51Ti49 alloy using the constrained effect of stress on driving force of TWSM material.When the snap-acting transition has been realized:M_s= M_f and A_s=A_f;hysteresis is rectangular,the height (TWSM effect) and width (hysteresis) of the rectangle can be readjusted by means of constrained stress.The results of resistance measurments show that,the snap-acting TWSM effect mentioned above was supplied mainly from the transformation of P←→R.The thermodynamic model has also been proposed to ac- count for the snap-acting transformation.
关键词:
transformation thermodynamics
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JI Jingwen WEI Quanjin GENG Dianqi WU Yuqin Northeast University of Technology
,
Shenyang
,
China Professor
,
Dept.of Physics
,
Northeast University of Technology
,
Shenyang 110006
,
China
金属学报(英文版)
The grain boundary internal friction(GBIF)in Fe-P and Fe-P-La alloys containing trace Cu has been studied.It is found that an addition of 0.584—0.722 wt-% La obviously reduces the IF,shifts grain boundary peaks towards higher temperatures,and produces a small addi- tional peak at even higher temperature.The mechanism of GBIF is explained as the movement of defects of atomic size,namely point defects,at gram boundaries and/or their clusters un- der stress.
关键词:
internal friction
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WANG Wencai CHEN Yu Peking University
,
Beijing
,
China Associate Professor
,
Dept.of Physics
,
Peking University Beijing
,
China
金属学报(英文版)
The short-range order structures of Fe_xGe_(1-x) amorphous thin films,(x=8.7,19.1 and 28.5%)have been studied by means of X-ray absorption spectrum.The nearest neighbors around a Ge or an Fe atom are constituted by two coordinate sub-shells with a very short dis- tance,In two films with lower Fe content,structural parameters of the nearest neighbors around a Ge atom are very near to that in amorphous germanium,and the positions of Fe at- oms are randomly substitutional.But when x=28.5%,some great changes occur on the short-range order structure of a-Fe_xGe_(1-x) film:its structure deviates from continuous ran- dora network and tends toward dense random packing of atoms.Meanwhile,there is a strong- er interaction between near neighboring Fe-Ge atoms in a-Fe_xGe_(1-x) films.
关键词:
Fe-Ge amorphous thin film
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