Structure and mechanical properties of rapidly solidified Mg-X alloys

We have investigated the structure and mechanical properties of binary Mg-X (X = Al, Ca, Li or Zn) melt-spun ribbons in as-quenched and annealed states as the first step of the development of alloy compositions for new Mg-based rapidly solidified powder metallurgy (RS P/M) alloys. The amorphous Mg₉₀Ca₁₀ and Mg₇₀Zn₃₀ (at%) alloys exhibited high specific tensile strength of more than 2.5×10⁵ Nm/kg and good bending ductility. Solid solubility extension was observed in Mg-Ca, Mg-Li and Mg-Zn RS alloys. The solid solution had a ductile nature for the Mg-Al and Mg-Zn RS alloys, while brittle for the Mg-Ca and Mg-Li RS alloys. The Mg-Ca and Mg-Zn RS alloys exhibited an abrupt increase in hardness by small addition of the alloying elements. The Mg₉₄Al₆, Mg₉₀Al₁₀, Mg₉₈Ca₂ and Mg₉₈Zn₂ RS alloys exhibited both high hardness and good bending ductility after annealing. It is expected that new magnesium RS alloys will be developed hereafter on the basis of these data.