Revealing the nucleation event of Mg-Al alloy induced by Fe impurity

作者：Liao, Hengbin; Mo, Liling; Zhou, Xiong; Yuan, Zhizhong; Du, Jun^*

来源：International Journal of Minerals Metallurgy and Materials, 2022, 29(7): 1317-1321.

DOI：10.1007/s12613-021-2406-z

• grain refinement
• Mg-Al alloy
• Al-Fe particle
• heterogeneous nucleation

This study revealed the nucleation event and grain refmement mechanism of Mg-Al alloy induced by Fe impurity. The following orientation relationship was observed between Al-Fe particle and alpha-Mg matrix in the Mg-3Al alloy containing Fe impurity using a focused ion beam aided transmission electron microscope technique: ((1) over bar 011)[01 (1) over bar1](Mg)//(01 (1) over bar)[011](Al2Fe). Mg-3Al alloy was inoculated by adding 0 02wt% Fe to verify the nucleating potency of the Al2Fe phase for a-Mg grain. The results indicated that Mg-3Al alloy was effectively refined with an average grain size declining from 1135 to 540 mu m. Among the potential Al-Fe phases of Mg-3Al-0.02Fe alloy, only the precipitation of the Al2Fe phase occurs earlier than that of a-Mg grain, and the Al2Fe phase is stable in the nucleation stage of a-Mg grain. Therefore, the Al2Fe particle is the only available nucleating site for Mg-Al alloy with Fe impurity. The heterogeneous nucleation event of alpha-Mg grain on the Al2Fe particle is responsible for the grain refinement of Mg-3Al alloy inoculated by Fe.

• 单位
  江苏大学