Zengqi ZHAO Lab.of Physics
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Baotou Research Institute of Rare Earth
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Baotou
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014010
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ChinaFeixia CHEN Dazhi YANG Dept.of Mater.Eng.
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Dalian University of Technology
,
Dalian
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116024
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ChinaEr BAO Dept.of Mater.Eng.
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Yanshan University
,
Qinhuangdao
,
066004
,
China
材料科学技术(英文)
Isothermal aging behaviours of a CuZnAl shape memory alloy have been investigated by means of dilatometry.The length of the specimens during isothermal aging from 190 to 280℃ increases with the aging time at each temperature.The isothermal aging kinetics fits in Avrami equation and the time exponent n decreases with the increase in aging temperature.The apparent activation energy for the isothermal aging process was measured to be 109.0kJ/mol,which is about equal to that of a relaxation internal friction peak at about 200℃ (f≈1 Hz) in the alloy.
关键词:
isothermal aging kinetics
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LI Dongchun TIAN Yongjun CHEN Shizhen YU Dongli HE Julong ** Yanshan University
,
Qinhuangdao
,
066004
,
China+ To whom correspondence should be addressed
材料科学技术(英文)
Nickel,as the carrier through which Fe atoms diffuse,obviously enhances the densification of sintered compact containing short cast iron fibre. When Ni content is above 4.5 wt-% there are some austenites in microstructure at room temperature, discontinuous cementite networks at the interfaces between austenites and pearlites,free graphite pre- cipitated in austenite and pores and Widmannst(?)tten carbide precipitated in austenite. When Ni content is about 12 wt-%,it leads to de- crease in densification ratio and change in fracture morphology of sintered compact from ductile to brittle.
关键词:
short metal fibre
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