Micro-compression of Al2Ca particles in a Mg-Al-Ca alloy

Laves phases with the AB2 stoichiometry are commonly found in Mg alloys. It is generally believed that Laves phases are brittle and detrimental for Mg's ductility. Recently, it was shown that in a dilute Mg-Al-Ca alloy, the Al2Ca phase can deform plastically, and the alloy exhibits high ductility and strong work hardening. In the present work, we further study the deformation of Al2Ca in a Mg-13Al-7Ca (wt.%) cast alloy by micropillar compression. Slip activities were observed in the deformed micropillars in both the Mg phase and the Al2Ca phase. The {0001}⟨1120⟩ basal slip was activated in all Mg micropillars with different crystal orientations, and the average critical resolved shear stresses (CRSS) was measured to be 16.9 MPa. The { 111 } ⟨110⟩ slip dominated the deformation in the Al2Ca micropillars, and the average CRSS was measured to be 164.9 MPa.

Automated summary

Laves phases with the AB2 stoichiometry are commonly found in Mg alloys. It is generally believed that Laves phases are detrimental for Mg's ductility. However, recent studies have shown that in Mg-Al-Ca alloys, the Al2Ca phase can deform plastically, resulting in high ductility and strong work hardening.