Properties of the surface of ceramic formed under laser irradiation of Al2O3–TiO2 compacts

• Published in: Applied surface science 2014-04, Vol.298, p.192-198
• Main Authors: Márquez Aguilar, P.A., Vlasova, M., Escobar Martínez, A., Tomila, T., Stetsenko, V.
• Format: Article
• Language: English
• Subjects: Al2O3–TiO2 mixtures; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Laser treatment; Phase formation; Physics; Surface products
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2014.01.161

•At directed laser treatment of x% Al2O3–y% TiO2 powder compacts in air the composite ceramics x% Al2TiO5–y% Al2O3–z% TiO2 are forming.•Due to formation of high temperature on the ceramic surface the processes dissociation of compounds take place.•Simultaneously dissociate components of the gas medium (and CO2 and H2O vapor).•At scattering the dissociation products turn out in different temperature zones and form new compounds.•Parts of the newly formed compounds are deposited on the surface of the ceramics and form a porous layer of complex composition. The phase formation in the laser irradiation area from xAl2O3–yTiO2 compacts and the properties of the surface layer have been investigated by the XRD, IR, and SEM methods. Main phases precipitating from eutectic melt are tialite, corundum, and rutile. A high temperature on the surface of specimens leads to the development of dissociation processes of these compounds and molecules of the gaseous medium. As dissociation products fly apart and pass through different temperature zone, there are formed different metal oxides, metal hydroxides, and thermolysis products. When these different oxides are deposited on the surface of the ceramic, they form layers with different adhesion degrees.