QIN Zuoxiang
,
ZHANG Yansheng
,
ZHU Naiping Department of Materials Engineering
,
Dalian Railway Institute
,
Dalian
,
116022
,
China.Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China.
材料科学技术(英文)
The oxygen relief/absorption,superconduc— tivity and structure of(Bi_(1-x)Pb_x)_2Sr_2Ca_2— Cu_3O_y compounds have been studied by TGA, electrical resistance measurement and X-ray diffraction.The amount of oxygen which can be re- leased and superconductivity of the compounds are correlative to Pb content.The release of oxygen in- creases when x less than 0.2 and decreases when x exceeds 0.2 with increasing x.The appropriate con- tent of Pb for superconductivity is in the range of 0.1
关键词:
oxygen relief/absorption
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null
,
null
,
null
GONG Hai
,
ZHANG Xiumu Department of Materials
,
Dalian Railway Institute
,
Dalian
,
116022 China.Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China.
材料科学技术(英文)
The morphology and substructure of mixed martensites in ferrous alloys have been examined by using optical and transmission electron microscope. The results indicated that the main formation se- quence of martensitic morphology was butterfly→ plate→lath,with decreasing forming temperatures when the plastic accommodation takes place in the parent phase,which is affected by the transforma- tion strain fiélds.It was shown that the martensite morphology is not only decided by the forming temperature alone,but also by the dislocation struc- ture in austenite before the transformation.
关键词:
martensite morphology
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null
,
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Z.M. Ding1)
,
Y. Lei2) and L.J. Lao1) 1)Department of Materials Engineering
,
Dalian Railway Institute
,
China 2)Department of Materials Science & Engineering
,
Dalian University of Technology
,
China
金属学报(英文版)
Theacicular austeniteformation process duringintercritical annealing atslow heating speedof0 5 ℃/ min isinvestigated using TEMin the sample of 30 CrMnSiA. The resultsshow thatinthe preliminarystage, austenitesnucleateintheform ofshortneedle atshort rod like cementites, which hasthesame orientation and precipitates along the boundary of original martensitelathes. Asthetemperatureincreasingslowly, the austenites grow up and connect witheach other alongtheboundaryoftheoriginallathesso astoform acicular austenite. At last,the fully grown austenite connectsin the direction verticalto the boundary of lathes, leavingthe remnant ferrites appear in the shape of rhombus, the original austenite grainshaperecovers and the feature of thethick lath remains. The superledgeinterface has been found and someaustenitegrowsintoferritein theshapeoflath.
关键词:
austenitictransformation
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null
,
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