The effect of Zn on the microarc oxidation coating behavior of synthetic Al-Zn binary alloys

► The coating thickness increased with Zn addition into substrate. ► The formation α-Al2O3 was suppressed and consequently hardness value of the coatings decreased with Zn content in the substrates. ► The increase in amount of Zn in Al, resulted in a rougher surface. ► Mullite and γ-Al2O3 phases existed on all coatings. α-Al2O3 phase was also detected on coated pure Al and Al-Zn alloys with 1-10 wt.% Zn.