The purpose of the diploma thesis was the fabrication of boehmite obtained by the sol-gel method in various forms boehmite coatings and powder. It was manufactured by the Yoldas process using aluminium-tri-sec-butoxide, ethyl acetoacetate, isopropyl alcohol and water. On the samples of epoxy resin, aluminium AC50, steel C45, titanium alloy GR2 and glass contact angles were measured and determined the hydrophilicity of the surfaces. Coatings were applied by dip-coating technique and dried in the dryer. Boehmite powder was made by drying and crushing the solution. For characterization of coatings and powder we have used scanning electron microscope (SEM) with energy-dispersive X-ray spectroscopy (EDXS).
It was found that sol-gel is a simple and clean process that allows us to prepare a solution at room temperature. Sól wetted the investigated materials well, we have measured low values of contact angles. The coatings on glass and aluminium alloy showed no cracks, while on the samples of titanium, epoxy resin and steel, the coatings were cracked. The thickness of the coatings was rated at approximately 1–2 m. Powder was obtained and we have rated the particles to be up to 500 m in size. The presence of boehmite, AlO(OH), was confirmed on the coatings and powder by EDXS analysis.
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