Characterization of the plasma electrolytic oxidation of titanium in sodium metasilicate

• Published in: Applied surface science 2013-01, Vol.265, p.226-233
• Main Authors: Stojadinović, S., Vasilić, R., Petković, M., Kasalica, B., Belča, I., Žekić, A., Zeković, Lj
• Format: Article
• Language: English
• Subjects: Coatings; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Density; Exact sciences and technology; Imaging; Infrared and Raman spectra; Infrared and raman spectra and scattering; Ionization; Materials science; Optical emission spectroscopy; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Oxidation; Physics; Plasma electrolytic oxidation (PEO); Rutile; Sodium; Sodium metasilicate; Structure and morphology; thickness; Surface treatments; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Titanium
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2012.10.183

▸ Plasma electrolytic oxidation (PEO) of titanium in sodium metasilicate. ▸ Spectroscopic study of the PEO process of titanium is conducted. ▸ Line shape analysis of hydrogen Hβ line, two electron number densities detected. Plasma electrolytic oxidation (PEO) of titanium in sodium metasilicate at 200mA/cm2 is investigated using real-time imaging and optical emission spectroscopy. It has been detected that during the PEO process the size of microdischarges becomes larger, while the number of microdischarges is reduced. The species and their ionization states present in PEO microdischarges are identified. The species originate both from titanium anode and from the electrolyte. The spectral line shape analysis of hydrogen Balmer line Hβ (486.13nm) indicates the presence of two types of microdischarges during PEO. The discharges are characterized by relatively low electron number densities of Ne=3.8×1015cm−3 and Ne=4.5×1016cm−3. For electron temperature (Te) measurement we used Ti I lines at 398.18nm and 501.42nm and obtained Te in the range of 3700±500K. Surface coatings formed by PEO process were characterized by AFM, SEM-EDX and XRD. The main elemental components of PEO coatings are Ti, Si and O. The PEO coatings are partly crystallized and mainly composed of anatase, rutile, and amorphous SiO2.