International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Lithium disilicate glass-ceramic is one of the most commonly used aesthetic materials in fixed prosthetics that requires surface pre-treatment. Recent studies have begun to propose a femtosecond laser for processing to improve surface morphology and microstructure, but without defined parameters. Therefore, the aim of this study is to determine the optimal parameters for the surface morphology of lithium disilicate glass-ceramics. The untreated sample of lithium disilicate glass-ceramic was observed with an optical profilometer. It was then treated with a femtosecond laser, forming squares on the surface of the sample, which were observed with an optical profilometer, and the surface morphology was analysed with a scanning electron microscope. The results show that laser treatment with higher energy densities leads to an increased roughness of the surface.

Present paper deals with the investigation of the surface morphology of pure titanium after anodization. Round samples of CP Ti were anodized at different voltages (16V, 20V, 25V, 30V and 40V) in an electrolyte containing 0.5 wt.% HF. The process duration varied from 30min to 7 hours. The samples’ surface was observed and EDX analysis was made by SEM. Surface morphology of CP Ti after anodization is defined by the surface roughness before anodization, electrolyte type and process parameters – voltage and duration. It was established that the surface of pure titanium after 3h-7h anodization at all voltages characterizes with large number of craters increasing the surface micro-roughness. At short-term processes only pores with about 2µm diameter were observed. Depending on the regimes used different oxide nanostructures were observed. After short-term anodization in lower voltages the titanium surface was covered with nanodots, nanorods and nanoflakes. Increasing the voltage up to 25 V led to originating of nano-tubular structure in some areas and sponge-like nano-structure at 30 V and 40 V. Increasing the process duration caused increase of the proportion of nanotubes and sponge- like structure to that of nanorods.

Structural investigations performed by the methods of X-ray diffractometry and scanning electron microscopy of electrodeposited iron-based coatings revealed common and specific features and regularities of influence of nickel and chromium on their structure formation. Significant changes in surface morphology, crystallographic texture and microhardness of the electrodeposited coatings caused by the insertion of nickel and chromium in the sulfate iron-plating electrolyte were found and compared.