Study On The Preparation And Properties Of Bioinspired Super-Slippery Al Surface

Aluminum and its alloys are widely used in automotive,aerospace,defense,biomedical and other fields due to their reliable mechanical properties,low price and good processing performance.However,it is susceptible to corrosion or icing damage in special environments such as marine engineering and cold areas,causing serious problems.Slippery liquid-infused porous surface(SLIPS)inspired by Nepenthes pitcher has attracted much attention of scientists because of its omniphobicity,self-cleaning,anti-icing and frosting,corrosion resistance,antifouling and self-healing properties.Contrast to the superhydrophobic surface which is easy to fail in pressure or easily damaged after scratching,slippery liquid-infused porous surface are prepared by infusing lubricating film into the micro-nano structure,forming a smooth liquid-infused surfaces at the molecular-level.These surfaces are demonstrated to possess advantages of extreme press stability,instant self-healing.It has good prospects in the fields of marine antifouling,coating protection and medical testing.On the basis of the theory of the construction mechanism of SLIPS surface,we present a simple and convenient approach to fabricate the SLIPS on Al substrate by electrochemical etching and anodization,superhydrophobic modification and silicone oil infusion.The as-prepared SLIPS showed a water roll-off angle of 3°,which could exclude almost all liquids at a small inclining angle.A series of characterizations of aluminum-based bioinspired super-slippery surfaces were carried out from the aspects of surface morphology,microstructure,crystal structure and element composition,thus revealing the mechanism of aluminum-based bioinspired super-slippery surfaces.It has been found that all the liquids could easily slide on the surface,demonstrating the excellent slippery property of the aluminum-based bioinspired super-slippery surfaces.Moreover,the sliding speed is negatively correlated with the kinematic viscosity of the liquid,regardless of their weight and contact angle.The mechanical properties and chemical stability tests of the aluminum-based bionic super-slippery surface showed that the aluminum-based bionic super-slippery surface has good mechanical stability,acid and alkali resistance and high temperature stability;The aluminum-based bioinspired super-slippery surface was evaluated from the anti-icing and ice-deicing properties.The deicing force was reduced by 91.8% compared with the ordinary aluminum surface,indicating that it has excellent anti-icing performance and easy deicing effect..The electrochemical impedance spectroscopy and polarization curves of the aluminum-based bioinspired super-slippery surface show that the corrosion current density was 4 orders of magnitude lower than that of the ordinary aluminum surface,and has excellent corrosion resistance property.The self-cleaning experiments on the aluminum-based bioinspired super-slippery surfaces verified that the surface has good self-cleaning properties.