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采用3m小型落管实现了Ag—28．1（质量分数，％下同）Cu共晶合金的微重力快速凝固，在高纯He和Ar的混合气氛中获得的合金小球直径在80—1000mm范围内．随着小球直径的减小，晶粒及层片共晶得到细化，凝固组织由层片共晶向不规则共品转变．TMK快速共晶生长理论的计算结果显示，Ag—28．1Cu层片共晶的最大生长速度、最小层片间距和最大过冷度分别为0．291m／s，0．017μm和193K．
Micro-gravimetric solidification of Cu-eutectic alloy Ag-28.1 (mass fraction,% same below) with 3m small drop tube was achieved. The diameter of the alloy spheres obtained in the mixed atmosphere of high purity He and Ar ranged from 80-1000mm Range. With the decrease of the diameter of the pellet, the eutectic of the grains and the lamellae are refined, and the solidified structure is transformed from the eutectic of the lamella to the irregular co-product. The calculated results of TMK rapid eutectic growth theory show that the maximum growth rate, the minimum interlamellar spacing and the maximum undercooling of Ag-28.1Cu layer are 0.291m / s, 0.017μm and 193K, respectively.