A study of nanoscale Al3(Zr,Yb) dispersoids structure and thermal stability in Al–Zr–Yb alloy

Structure and thermal stability of nanoscale Al3(Zr,Yb) dispersoids in Al–Zr–Yb alloy was studied by TEM, OM observation combined with XRD, SAED, EDAX and hardness analysis. The results showed that addition of Zr and Yb forms high-density homogeneous Al3(Zr,Yb) dispersoids with coherent cubic L12 structure, compared to add Zr. Al3(Zr,Yb) dispersoids contains two types, which one is Yb incorporating Al3Zr, the other is Zr incorporating Al3Yb. Zr incorporating Al3Yb dispersoids exhibit unique core/shell structure, which structure leads to have better thermal stability and inhibit-recrystallization ability compared to Al3Zr in pure aluminum.