Preparation And Characterization Of Aluminum Oxide Coatings

Here,we report aluminum oxide nanowire strctures with hydrophobic properties,prepared using a environmental-friendly facile sol-gel method by magnetic stirrer and hydrothermal reaction.It solves the problem that high temperature and high pressure are needed for the traditional process,and reduces the cracks of aluminum oxide coating.The influence of different conditions on the microstructure and surface morphology of Al2O3 coating in hydrothermal reaction was studied,and the influence factors of alumina performance,micro structure and morphology,surface wettability,composition and surface adhesion were deeply analyzed.With the change of water content in hydrothermal reaction,the crystal structure of aluminum oxide appears as including disperse granular,globular particles,rectangular pyramid and nanowire.The effect of water content during the hydrothermal reaction has also been investigated on the nanoparticle morphology and surface wettability properties of Al2O3 films.From SEM,TEM,XRD,WCA,XPS and 3M adhesion test characterization results,the wettability of Al2O3 films can be controlled by water content in hydrothermal reaction,in which 10ml is hydrophobic and 20ml hydrophilic.The differences of microstructure and surface properties of Al2O3 films by different driving forces during sol-gel process.With the increase of water content in hydrothermal reaction,the hydrophobicity of Al2O3 films proportional increased.Adding 10 ml deionized water leads to the formation of the upper nanowires and the lower nanohole with 129.3 ° water contact angle.In order to apply the aluminum oxide films to the packaging of moisture and corrosion,different packaging materials were selected as the basis,such as aluminum,titanium,tinplate and glass.At the same time,the Al2O3 films provide a good substrate for electroless deposition of copper to achieve a simple manufacture of metal conductor,and conductivity of 10ml sample is the higest.The results show that the excellent conductivity of copper coating is mainly attributed to the structure of alumina coating,and the compact integrity of copper coating on aluminum coating is the leading factor for the formation of excellent conductivity.