(1. 东北大学 材料电磁过程研究教育部重点实验室，沈阳 110004；
2. 东北大学 材料科学与工程学院，沈阳 110004；
3. 辽宁石油化工大学 机械工程学院，抚顺 113001)
摘 要: 研究冷却速率对Al-5Zr中间合金中Al3Zr相尺寸形貌的影响，并分析冷却速率对Al3Zr相形核与长大速率的影响。结果表明：随冷却速率由耐火模的2.0 ℃/s提高到铜模的45.6 ℃/s，初生Al3Zr相由粗大板条状转变成细小的片层状。当冷却速率分别为2.0、29.3和45.6 ℃/s时，试样中初生Al3Zr相长轴平均长度分别为215、175和45 μm，对应最大尺寸Al3Zr相的长轴长大速率分别为5.4、53.2和38.4 μm/s，试样中形核数量分别为23、54和309 mm-2。
关键字: Al-Zr中间合金；冷却速率；凝固组织；形核
（1. Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang 110004, China;
2. School of Materials Science and Engineering, Northeastern University, Shenyang 110004, China;
3. School of Mechanical Engineering, Liaoning Shihua University, Fushun 113001, China）
Abstract:The effects of the cooling rate on the morphology and size of the primary Al3Zr phase during solidification process were investigated. Base on the experiment results, the effects of the cooling rate on the nucleation and growth rate of the primary Al3Zr phase also were analyzed. The results show that with the cooling rate increasing from 2.0 ℃/s to 45.6 ℃/s, the coarse plate shape primary Al3Zr phases change to fine needle shape. When the cooling rates are 2.0, 29.3 and 45.6 ℃/s, respectively, the average lengths of the primary Al3Zr phase are 215, 175 and 45 μm, respectively, the growth rates along the major axes of the maximum size Al3Zr phase in the corresponding sample are 5.4, 53.2, 38.4 μm/s, respectively, and the nucleation numbers of the primary Al3Zr phase are about 23, 54, and 309 mm-2, respectively.
Key words: Al-Zr master alloy; cooling rate; solidification structure; nucleation
