Porous coatings obtained on titanium after IMPULSE – PEO processes

The surface stereometry and chemical compositions of porous coatings obtained during Plasma Electrolytic Oxidation, PEO / (Micro Arc Oxidation, MAO) processes with use of impulse regime with different frequencies were the main goal of discussions presented in that paper. All the coatings were characterized by Scanning Electron Microscope (SEM), Energy-dispersive X-ray Spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS). It was found out that the frequencies of voltage signals used in PEO process as well as their duty ratios have a big influence on porosity, roughness and chemical composition of fabricated layers. In addition, it was noted that all the coatings' compounds contained Ti⁴⁺ and Ca²⁺ or Mg²⁺ as well as PO₄ ^3–, and/or HPO₄ ^2–, and/or H₂PO₄ ^–, and/or P₂O₇ ^4–. (paper)