(1. 北京科技大学 材料先进制备技术教育部重点实验室，北京 100083;
2. 北京科技大学 新材料技术研究院，北京 100083)
摘 要: 将结晶器移出感应加热器，使连续定向凝固时固液界面控制在结晶器出口；结合传热边界条件，求解连续定向凝固熔体区、液/固界面、空冷区和水冷区的一维稳态温度场方程，得出线坯最大稳态拉坯速度随熔体温度、结晶器长度、冷却距离和冷却水流量的变化规律；并基于直径为6 mm的Cu-12%Al(质量分数)线材制备的工艺条件，对理论解进行实验验证和讨论。结果表明：Cu-12%Al线材的最大稳态拉坯速度随熔体温度升高而降低，且降低速率逐渐减小，其中在1 150~1 300 ℃范围内降低37.3%；最大稳态拉坯速度随结晶器长度增加而增加，且增加速率逐渐减小，其中在20~40 mm范围内增加28.5%；最大稳态拉坯速度随冷却距离增加而降低，且降低速率逐渐减小，其中在4~12 mm范围内降低68.8%；冷却水流量在100~400 L/h范围内最大稳态拉坯速度变化不明显。当固液界面前沿温度梯度小于2.02 ℃/mm时，实际拉坯速度无法达到理论最大稳态拉坯速度；当固液界面前沿温度梯度大于4.17 ℃/mm时，最大稳态拉坯速度实验值和理论值吻合较好。
关键字: Cu-12%Al线材；拉坯速度；温度场；结晶器长度；温度梯度
Cu-12%Al wires during OCC
（1. Key Laboratory of Advanced Materials and Manufacturing Technologies, Ministry of Education,
University of Science and Technology Beijing, Beijing 100083, China;
2. Institute for Advanced Materials and Technologies,
University of Science and Technology Beijing, Beijing 100083, China）
Abstract:By moving out of induction heater for crystallizer, the solid-liquid interface was controlled at the exit of crystallizer during Ohno continuous casting(OCC). Based on the temperature field equations of melt region, liquid/solid interface, air cooling region and water cooling region, the relationship was deduced among the maximum steady-state drawing velocity, melt temperature, crystallizer length, cooling distance and water flow rate by using thermal boundary conditions. Through the solidification process of Cu-12%Al(mass fraction) wires with a diameter of 6 mm, the theoretical solutions were verified and discussed. The results show that, the maximum steady-state drawing velocity for Cu-12%Al wire decreases by 37.3% in the range of 1 150−1 300 ℃ with increment of melt temperature, increases by 28.5% in the scope of 20−30 mm with increment of crystallizer length, and decreases by 68.8% in the range of 4−12 mm with increment of cooling distance, changes weakly with cooling water flow rate in the range of 100−400 L/h. When the thermal gradient at solid-liquid interfaces is lower than 2.02 ℃/mm, the experimental drawing velocity cannot reach the theoretical maximum steady-state drawing velocity. When the thermal gradient at solid-liquid interface is higher than 4.17 ℃/mm, there is a good agreement between the experimental and theoretical values of the maximum steady-state drawing velocity.
Key words: Cu-12%Al wire; drawing velocity; temperature field; crystallizer length; thermal gradient
