Reversible switching of wettability based on shape memory effect

The present letter describes a new strategy of achieving reversible switching of wettability on shape memory alloy (SMA) surface with pre-deformed treatment. Due to the two-way shape memory effect of the SMA, residual strain hidden in SMA substrate could be activated under thermal cycling condition and microstructure appears repeatedly on the surface layer of the SMA. The static water contact angle of SMA surface was improved about 50° and reversible switching of wettability was realized by their transformed surface morphologies, demonstrating the potential of constructing smart surface with reversible wettability based on shape memory effect.