X.L.Yang1)
,
X.Sun2)
,
C.W. Wang 2)
,
D.Q. Geng2)and C.M. Liu 2) 1)Schoolof Mechanical Engineering and Automation
,
Northeastern University
,
Shenyang 110006
,
China 2)Schoolof Material & Metallurgy
,
Northeastern University
,
Shenyang 110006
,
China
金属学报(英文版)
Thispaperintroducesa valve which useshape memory alloys( SMA) fortemperaturecon trol, which makes useof deformation of SMAcaused by variation oftemperaturetocontrolmechanical parts. Thevalvecan beswitched on or off automatically and hasthe advantages ofsimplestructureand reliable performance.Itcan beusedin adverse workingconditionsor conditions with lower requirementson controlling precision ofthetemperatures. Consequent ly,it hasextensive application prospects.
关键词:
shape memory alloy
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null
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C. M. Liu1)
,
K. Abiko2) and M. Tanino2) 1) Schoolof Materials and Metallurgy
,
Northeastern University
,
Shenyang 110006
,
China 2) Institute for Materials Research
,
Tohoku University
,
Sendai980
,
Japan
金属学报(英文版)
Effectoftheintergranularsegregationof Sonthehot ductilityof high purityiron wasquan titativelyinvestigated using high purityiron specimenscontaining < 2 ,5,10 ,20 and 60massppm Sby scanning AES,tensiletests under high vacuum and SEMof the fracturedsurface. The main resultsareasfollows: high purityironcontaininglessthan 2 massppm Sexhibitsanexcellenthotductility,thatis,reductionofareatofracturelargerthan95 % ,at alltesttemperaturesbetween673 and 1173 K. Dissolved Sof5 massppm causesanevident hot ductility dropof high purityiron at873~973 K.Increasingthedissolved Scontentfur ther decreases hot ductility and widensthetemperaturerange ofembrittlement. Theembrit tledspecimensfailinintergranular mode. Theamountoftheequilibrium intergranularseg regation of Sincreases withincreasingtheconcentration of dissolved Sand with decreasingthe annealingtemperature. Ssegregates much moreon cavitysurfacesthan atgrain boundaries.
关键词:
high purityiron
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null
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null
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null
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null
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C. M. Liu1)
,
K. Abiko2) and M. Tanino2) 1) Schoolof Materials and Metallurgy
,
Northeastern University
,
Shenyang 110006
,
China 2) Institute for Materials Research
,
Tohoku University
,
Sendai980 8579
,
Japan
金属学报(英文版)
Theeffectof phosphorusonthehotductility andthesegregation ofsulfuratgrain boundariesin high purityironcontaining 0 002 % sulfur werequantitativelyinvestigated bytensiletestat973 K, SEMobservation of fracture surface and scanning Auger electron spectroscopy.Theexperimental resultscan besum marized as follows:(1) addition of phosphorustothe iron remarkablysuppressestheintergranular fractureinduced bythesegregation of sulfur at973 Kandincreasesthe hot ductility;(2) phosphorusstrikingly decreasesthesegregation ofsulfur atgrain boundaries, whichisresponsibleforthesuppressionoftheintergranularfrac tureat973 K;(3) theremarkably decreasedsegregation ofsulfur atgrain boundariesbytheaddition of phosphoruscan beexplained bythesitecompetitioneffectandtherepulsiveinter action at grain boundariesbetweensulfuratomsand phosphorusatoms;(4) sulfurstrikinglysegregatestothevoid surfacesformed on grain boundaries, while phosphorushaslittlesegre gationtothevoid surfaces.
关键词:
high purity iron
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null
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null
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null
Y.N.Wang1)
,
B.L.Wu2)
,
L.Zuo1) and Z.D.Linag1) 1) Department of Materials Science & Engineering
,
Northeastern University
,
Shenyang 110006
,
China 2) Shenyang Institute of Aeronautical Engineering
,
Shenyang 110034
,
China
金属学报(英文版)
Heating rate playsanimportantroleon recrystallizationtextureofcold deformed metals.Inthispaper,thelaser heatingtechnique wasusedtotheultrarapidlyannealingon acold rolledCu 30 mass% Zn alloy. The experimental resultsshow thatthe texture development differs from those observed in the case of conventional annealing. When primary recrystallization completes,the grainsizeisvery fineandthegrain orientation distributionisalmostrandom . Withthecontinuousgrain growing,the dispersioncharacterofthegrainorientationsstillre mains. The possible mechanismson theevolution of ultrarapid recryctallization texture were discussed.
关键词:
Cu 30 mass% Zn alloy
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null
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S.M. Hao
,
X.J. Hao
,
G. Zhao and H.X. Li Schoolof Materials and Metallurgy
,
Northeastern University
,
Shenyang 110006
,
China
金属学报(英文版)
Theinteraction ofspinodaldecomposition and recrystallization process,andthecharacteristic ofrecrystallizationin Cu Ni Fe alloy aged atdifferenttemperaturesaftersolution treatmentandcold rolling have been studied by structural analysis and Vickers hardnesstest. It has shownthat the recrystallization of spinodal Cu Ni Fe alloy might be divided into 2 types:spinodal decomposition, recovery and recrystallization oftwo phase microstructuretook placein the deformed alloy aged below thespinodaltemperature; whilerecrystallization ofsingle phase microstructureand growth offullyrecrystallized grainstook placeinthedeformed al loy aged abovethespinodaltemperature .The deformed alloyaged below thespinodaltemper aturerecrystallizedin cellular morphology.
关键词:
spinodaldecomposition
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