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Grain refinement of Mg–10Gd alloy by Al additions

  • Jichun Dai (a1), Mark Easton (a2), Suming Zhu (a2), Guohua Wu (a3) and Wenjiang Ding (a3)...


The addition of Al to a Mg–10Gd alloy was found to lead to substantial grain size reduction during casting at concentrations between 0.8% and 1.3%. At these concentrations, Al2Gd particles were found at the center of grains, and the orientation relationship $[112]_{{\rm{Al}}_{\rm{2}} {\rm{Gd}}} \,{\rm{‖}}\,[2\bar 1\bar 10]_{{\rm{\alpha - Mg}}} ,\,(1\bar 10)_{{\rm{Al}}_{\rm{2}} {\rm{Gd}}} \,{\rm{‖}}\,(0\bar 110)_{{\rm{\alpha - Mg}}} $ was found reproducibly between Al2Gd and α-Mg, indicating that these are the heterogeneous nucleant particles that form in situ at these Al contents. Most of these nuclei were between 2 and 7 μm in size. Furthermore, little grain coarsening was observed during solution treatment, particularly compared with an alloy grain refined by Zr particles where substantial coarsening occurred. This appears to be because Al2Gd particles restrict grain boundary motion during solution treatment.


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Grain refinement of Mg–10Gd alloy by Al additions

  • Jichun Dai (a1), Mark Easton (a2), Suming Zhu (a2), Guohua Wu (a3) and Wenjiang Ding (a3)...


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