W.Q.Zhang
,
L.Xiao
金属学报(英文版)
A numerical model is established to simulate the concentration field in irregular lamel-lar eutectic of Al-Si system.Both the undercooling and spacing are dependent on thegrowth rate and the temperature gradient,and increasing growth rate causes an in-crease of undercooling but a decrease of lamellar spacing,while increasing temperaturegradient leads to a decrease of lamellar spacing.The computed results are in goodagreement with experimental observations.
关键词:
irregular eutectic
,
null
,
null
,
null
W.Q
,
Zhang
,
L.Xiao
金属学报(英文版)
A numerical model has been established to calculate the primary spacing of cellular or dendritic structure with fluid flow considered。 The computing results show that the primary spacing depends on the growing velocity, the temperature gradient on the interface and fluid flow. There is a critical growing velocity for the cell-dendrite transition, which has a relationship with the temperature gradient: Rσ = (3-4)×10^-9GT. Fluid flow leads to an increase of the primary spacing for dendritic growth but a decrease for cellular growth,resulting in an instability on the interface.
关键词:
primary spacing
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null
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null
