and more attractive as structural materials due to their
light weight, low cost, and recyclability. However, their
strength is often inadequate for many engineering applications.
Among the currently developed Mg alloy families,Mg-Al-Ca–based alloys exhibit advantages in
several aspects such as high creep resistance and super
light weight due to the very low densities of the constituent
elements (density of magnesium = 1.74 g/cm3, density of aluminium = 2.70 g/cm3, and
density of calcium = 1.54 g/cm3).
In addition, the Ca element in the
alloys serves to protect the melt surface from fast
oxidation, resulting in less slag formation, during processing.
However, the yield strength of the Mg-Al-Ca
alloys remains at a low level around 160 to 250 MPa at
ambient temperature below 450 K.[1]Adramatic strength
enhancement has not been possible, based on the conventional
strengthening approaches such as grain refinement,
solid solution, and precipitation.
