综合采用熔融玻璃净化、铜模喷铸及单辊旋淬技术，对比研究不同过冷度、不同冷速作用下 Cu?Co 不混溶合金的快速凝固行为。通过对凝固发生时的热流方式、形核及生长过程的分析，阐述合金非平衡组织由枝晶到分相结构的转变及其相应尺寸的变化规律。随过冷度增加，不混溶效应的增强导致柱状枝晶向分相结构转变。由于铜模喷铸时发生多点形核，凝固组织呈现为等轴枝晶并随冷速增加而不断细化。当喷铸试棒直径为4 mm时，不混溶效应形成的液滴由于长大不充分最终形成细小粒状分相组织。单辊旋淬薄带由于冷速最高，凝固过程瞬间完成，可有效抑制液相分离的发生，有利于胞状单相固溶体组织的形成。
Rapid solidification of Cu?Co immiscible alloy was investigated by glass-fluxing, spray casting and melt-spinning techniques. Both the transition from dendrite to dispersive structure and corresponding scale evolution were revealed and further elucidated in terms of the heat flow mode, nucleation and growth processes under different solidification conditions. With the increase of undercooling, columnar dendrite is replaced by dispersive structure due to the immiscible effect. In contrast, equiaxed dendrite forms in spray cast alloydue to multiple nucleation events and becomes thinner for the case of higher cooling rate. Ascribed to the enhanced non-equilibrium effect and insufficient period for collision and coagulation processes between separated droplets, fine globular dispersionappears upon the diameter of spray casting reaching 4 mm. As for the melt-spun ribbon withthehighest cooling rate, a single-phase solid solution microstructure with refined grain of cellular morphology can be obtained, which is attributed to the suppression of liquid phase separation by instant solidification.
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