Second phases of rapidly solidified AlFeCrZrVSi alloy and their thermal stabilities

Abstract

The rapidly solidified powder of AlFeCrZrVSi aluminum alloy was prepared using multi-stage atomization and consolidated by hot-extrusion, the evolution of microstructure of the extruded materials during thermal exposure was studied with optical microscope, X-ray diffraction and transmission electron microscope (TEM). The results show that the majority of dispersions present in the as-extruded alloy are metastable Al₁₂ (Fe, Cr, V)₃Si, which has excellent thermal-dynamical stability and coarsening resistance; the coarsening rate-controlling process of the Al₁₂ (Fe, Cr, V)₃Si phase is considered to be diffusion of Fe atom along grain boundaries instead of bulk diffusion of Fe atom.

Keywords

aluminum alloy / rapid solidification / thermal stability