The influence of the dew point on the wettability of twinning-induced-plasticity steels by liquid Zn–0.23-wt% Al

•Selective oxidation of Twining-induced plasticity (TWIP) steel was investigated.•Selective oxidation on the surface of TWIP steel was affected by gas atmosphere.•The wettability of TWIP steel by liquid Zn–Al alloy was examined.•The wettability of TWIP steels was improved by controlling the dew point.