Micrometric grained Al synthesized via quasi-hydrostatic ultra-high pressure consolidation of micrometric Al powders

•Ultra-high pressure (UHP) can disrupt oxide films on powder surfaces.•Micrometric grained (MMG) Al can be synthesized via UHP consolidation of Al powders.•MMG Al synthesized via UHP consolidation exhibits high strength and ductility.

This paper reports a study on the synthesis of a fully dense micrometric grained (i.e., grain size around 1 μm) Al via consolidation of spherical micrometric-sized Al powders under a quasi-hydrostatic ultra-high pressure of 5 GPa. Our result shows that during consolidation oxide films on powder surfaces can be effectively disrupted into nano-scale oxide particles, which promoted the formation of metallurgical bonding between powders and the retention of micrometric-sized grains. Consequently, the as-consolidated Al is characterized by micrometric grains (average grain size of 1.2 μm) with a high density of nanoscale oxide particles (average size of ~25 nm) at grain boundaries. The as-consolidated Al exhibits both high strength (ultimate tensile strength of ~130 MPa) and ductility (uniform elongation of ~10%).