The promoted formation of an α-Al2O3 scale on a nickel aluminide with surface Cr2O3 particles

•Significant θ-to-α Al2O3 transformation occurred on Ni2Al3 at 1000°C.•Ni2Al3 coating were spread with a loose Cr2O3 particle layer by using electrophoretic deposition.•The Cr2O3 particles on the Ni2Al3 dramatically promoted the α-Al2O3 formation.•Cr2O3 as crystallographic template for the nucleation of isostructural α-Al2O3 is proposed.