Abstract A small amount of cerium (below 1.0 wt%) addition to AZ91 alloy have been investigated on the hot tearing susceptibility (HTS) at a cooling rate of 1.5Ks−1. The HTS increased to a maximum value with a cerium addition of 0.6 wt% and then decreased to a stable status as cerium was gradually added. Due to high chemical activity, cerium into the melts can react with aluminum to form an Al11Ce3 intermetallic compound. X–ray diffraction results also confirmed the existence of Al11Ce3. The Al11Ce3 increased with the presence of the needle-like and block morphology. As cerium levels increased, the amount of Mg17Al12 decreased. The variations between Mg17Al12 and Al11Ce3 resulted in a similar normal distribution of the HTS in AZ91 alloy. The findings were further verified through the microstructure evolution and the surface morphology of fracture.

中文翻译：

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Ce添加量对AZ91合金热裂行为的影响

摘要 研究了在 AZ91 合金中添加少量铈（低于 1.0 wt%）对冷却速率为 1.5Ks−1 时的热撕裂敏感性（HTS）的影响。HTS随着铈添加量增加到0.6wt%的最大值，然后随着铈的逐渐添加而下降到稳定状态。由于化学活性高，熔体中的铈可以与铝反应形成Al11Ce3金属间化合物。X 射线衍射结果也证实了 Al11Ce3 的存在。Al11Ce3 随着针状和块状形态的存在而增加。随着铈含量的增加，Mg17Al12 的量减少。Mg17Al12 和 Al11Ce3 之间的变化导致 AZ91 合金中 HTS 的类似正态分布。通过微观结构演变和断裂的表面形态进一步验证了该发现。