Open AccessRapid dendritic growth in highly undercooled ternary Ni-Cu-Co alloy
Author(s) -
Zang Du-Yang,
Wang Hai-peng,
B. Wei
Publication year - 2007
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.56.4804
Subject(s) - supercooling , materials science , microstructure , dendrite (mathematics) , alloy , ternary operation , differential scanning calorimetry , phase (matter) , thermodynamics , recalescence , diffusion , magnetic levitation , metallurgy , eutectic system , chemistry , physics , geometry , mathematics , organic chemistry , quantum mechanics , computer science , magnet , programming language
Rapid dendritic growth in undercooled liquid Ni80Cu10Co10 alloy has been investigated. This liquid ternary alloy was undercooled by a large degree up to 335 K(0.2TL) with electromagnetic levitation method. The rapidly solidified microstructure is revealed to be α-Ni solid solution phase by X-ray diffraction and differential scanning calorimetry. With the increase of undercooling, the microstructure is drastically refined. Its morphology transfers from coarse dendrite into equiaxial grains when undercooling exceeds 110 K. The solute microsegregation is suppressed with the enhancement of solute trapping effect under high undercooling condition. The dendritic growth velocity was measured as a function of undercooling. At extremely large undercoolings, the dendritic growth velocity of α-Ni phase is restrained by the solute diffusion of Cu and Co, and even decreases once undercooling exceeds 284 K.