采用定向凝固的方法研究了Ce对Al—2%Cu合金结晶形貌及一次枝晶间距的影响,结果表明,Ce增加了合金胞状生长的不稳定性;在Ce含量较小的情况下一次枝晶间距减小,在0.1～0.2%Ce范围内达到最小值,大于此范围时,一次枝晶间距反而增大。作者认为等价浓度C_(m n)是Ce影响界面稳定性及一次枝晶间距的主要因素。 The effect of Ce on the crystalline morphology and primary dendrite spacing of Al-2% Cu alloy was investigated by directional solidification. The results show that Ce increases the instability of the cellular growth of the alloy. When the content of Ce is small, The intergranular spacing decreases and reaches the minimum within 0.1 ~ 0.2% Ce. Above this range, the interdendritic spacing increases. The authors believe that the equivalent concentration of C_ (m n) Ce is the main factor affecting the stability of the interface and the primary dendrite spacing.