TY - JOUR
T1 - Core-shell microstructure formed in the ternary Fe-Co-Cu peritectic alloy droplet
AU - Dai, Fuping
AU - Wei, Bingbo
PY - 2009/4
Y1 - 2009/4
N2 - The metastable liquid phase separation occurs in the ternary Cu 50Fe37.5Co12.5 peritectic alloy droplets during free fall. The separated alloy melt rapidly solidifies and evolves core-shell microstructure composed of L1(Cu) and L2(Fe,Co) phases. Based on the determination of the phase transition temperature, the core-shell microstructure evolution, the interfacial energy, the temperature gradient and the Marangoni migration are analyzed. The interfacial energy of the separated liquid phase increases with the decrease of the temperature. The temperature gradient changes from large to small along the radius direction from inside to outside in the alloy droplet. The Marangoni force (F M) acting on the micro-droplet of L2(Fe,Co) phase increases with the increase of the size of the L2(Fe,Co) phase, and decreases with the increase of undercooling. Driven by F M, the micro-droplet of L 2(Fe,Co) phase migrates from outside to inside in the alloy droplet, collides and coagulates each other during migration, and then forms different types of core-shell microstructures.
AB - The metastable liquid phase separation occurs in the ternary Cu 50Fe37.5Co12.5 peritectic alloy droplets during free fall. The separated alloy melt rapidly solidifies and evolves core-shell microstructure composed of L1(Cu) and L2(Fe,Co) phases. Based on the determination of the phase transition temperature, the core-shell microstructure evolution, the interfacial energy, the temperature gradient and the Marangoni migration are analyzed. The interfacial energy of the separated liquid phase increases with the decrease of the temperature. The temperature gradient changes from large to small along the radius direction from inside to outside in the alloy droplet. The Marangoni force (F M) acting on the micro-droplet of L2(Fe,Co) phase increases with the increase of the size of the L2(Fe,Co) phase, and decreases with the increase of undercooling. Driven by F M, the micro-droplet of L 2(Fe,Co) phase migrates from outside to inside in the alloy droplet, collides and coagulates each other during migration, and then forms different types of core-shell microstructures.
KW - Core-shell microstructure
KW - Liquid phase separation
KW - Reduced gravity
KW - Ternary peritectic
UR - http://www.scopus.com/inward/record.url?scp=64549124813&partnerID=8YFLogxK
U2 - 10.1007/s11434-009-0103-9
DO - 10.1007/s11434-009-0103-9
M3 - 文章
AN - SCOPUS:64549124813
SN - 1001-6538
VL - 54
SP - 1287
EP - 1294
JO - Chinese Science Bulletin
JF - Chinese Science Bulletin
IS - 8
ER -