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在自制的单晶连铸设备上， 通过各工艺参数合理匹配， 成功地制备出了表面光洁、直径８ｍ ｍ 、长８ ～１０ ｍ 的铜单晶铸棒。通过理论分析和实验验证发现铜单晶连铸时固液界面位于铸型内， 并呈凸出形状。铸型温度、连铸速度和冷却距离对固液界面的位置有很大的影响， 其各工艺参数合理匹配， 可使固液界面位置位于离铸型出口端２ ～３ ｍ ｍ ； 并且当连铸速度大于４０ ｍ ｍ／ｍｉｎ 时， 固液界面的形状由凸变凹。当铸型温度逐渐降低（ 低于铜熔点温度） 时， 铸棒表面由粗糙变为拉伤， 甚至出现严重的拉裂； 而随着连铸速度的增加， 形成铸棒表面拉伤（ 低温时） 和条纹状沟槽（ 高温时） 。铸棒内的杂晶是由于铸型温度低于铜的熔点（１０８３ ℃） 和连铸速度增加所致。当连铸速度大于４０ ｍ ｍ／ｍｉｎ 时， 形成定向凝固的柱状晶铸棒
In the homemade single crystal continuous casting equipment, the copper single crystal cast rods with smooth surface, diameter of 8m m and length of 8 ~ 10m were successfully prepared through reasonable matching of process parameters. Through theoretical analysis and experimental verification, it is found that the solid-liquid interface of copper single crystal continuous casting is located in the mold and has a convex shape. The temperature of mold, casting speed and cooling distance have a great influence on the location of solid-liquid interface. The reasonable matching of process parameters makes the position of solid-liquid interface lie 2 ~ 3 m m away from the exit of mold. When the casting speed is more than 40 m m / min, the shape of the solid-liquid interface is convex. When the mold temperature is gradually decreased (below the melting point of copper), the surface of the cast rod changes from rough to tensile even severe cracking; and as the casting speed increases, ) And striped grooves (at high temperature). The miscellaneous grains in the cast rod are caused by the increase of the mold temperature below the melting point of copper (1083 ° C) and the continuous casting speed. When the casting speed is greater than 40 m m / min, the formation of directional solidification of the rod crystal rod