Microstructural transformations of TiO2, Al2O3+13TiO2 and Al2O3+4OTiO2 at plasma spraying and laser engraving

The paper deals with the investigation of microstructure of plasma sprayed and laser engraved coatings of TiO2 and Al2O3-TiO2 of two compositions (13 and 40 wt.% TiO2). The samples preparation technology includes also grinding and polishing prior to laser treatment. Transformations of crystal phases, present in initial powders, at all technological steps were investigated using X-ray diffraction (XRD) and Raman spectroscopy. Quantitative chemical analysis was carried out using X-ray photoelectron spectroscopy (XPS). Finally, morphology of powders and coatings surfaces and sections were investigated using scanning electron (SEM) and optical microscope (OM).