Liquid Cu_(70)Co_(30) alloy is undercooled up to 363 K(0.22TL)by using glass-fluxing technique.The LKT/BCT dendritic growth theory is modified and made applicable to predict the kinetic characteristics of dendritic gr...Liquid Cu_(70)Co_(30) alloy is undercooled up to 363 K(0.22TL)by using glass-fluxing technique.The LKT/BCT dendritic growth theory is modified and made applicable to predict the kinetic characteristics of dendritic growth in those alloy systems which have extremely curved liquidus and solidus lines.Actual calculations reveal that the dendritic growth of primary α-Co phase in Cu_(70)Co_(30)alloy is constantly controlled by solute diffusion.The growth velocity of α-Co dendrite has a maximum value of 54.5mm/s at an undercooling of 333K.The calculated solubility of Cu in α-Co dendrite decreases with the increase of undercooling,which agrees well with the experimental data.Prior to peritectic transformation,the growth of α-Co dendrite is close to equilibrium solidification.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.59425002Chinese National High Technology Program(No.863-2-4-3-2).
文摘Liquid Cu_(70)Co_(30) alloy is undercooled up to 363 K(0.22TL)by using glass-fluxing technique.The LKT/BCT dendritic growth theory is modified and made applicable to predict the kinetic characteristics of dendritic growth in those alloy systems which have extremely curved liquidus and solidus lines.Actual calculations reveal that the dendritic growth of primary α-Co phase in Cu_(70)Co_(30)alloy is constantly controlled by solute diffusion.The growth velocity of α-Co dendrite has a maximum value of 54.5mm/s at an undercooling of 333K.The calculated solubility of Cu in α-Co dendrite decreases with the increase of undercooling,which agrees well with the experimental data.Prior to peritectic transformation,the growth of α-Co dendrite is close to equilibrium solidification.