Industry 4.0
Vol. 10 (2025), Issue 6, pg(s) 200-203

DOMINANT TECHNOLOGIES IN “INDUSTRY 4.0”

“Optical characterization of thin films deposited on Ti-6Al-4V substrate by spectroscopic ellipsometry”

  • 1 Institute of Metal Science, Equipment, and Technologies ―Acad. A. Balevski with Center for Hydro- and Aerodynamics at the Bulgarian Academy of Sciences, Sofia, Bulgaria

Abstract

Spectroscopic ellipsometry was applied to study the optical properties of Ti–6Al–4V alloy before and after anodization in acetic acid electrolyte. The main findings can be summarized as follows: The ellipsometric spectra of the uncoated alloy were successfully modeled using a multi-Lorentz oscillator approach with MSE values of 20–26, and surface roughness ranging from 17 to 52 nm. Anodized surfaces exhibited distinct interference features, confirming the formation of a transparent oxide layer. The optical modeling revealed increased surface roughness and modified optical constants due to the formation of a TiO₂ -based film with amorphous–anatase character. The applied ellipsometric methodology proved reliable for evaluating the thickness and optical properties of anodic oxide films on titanium alloys. These results form the basis for future quantitative analysis of anodic oxide thickness and refractive index as functions of anodizing parameters, which is important for optimizing the surface properties of titanium alloys in biomedical, protective, and optical applications.

Keywords

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