Characterization of Corrosion Products on TiSi, TiAl, and WTi Coatings

• Published in: Metals (Basel ) 2024-10, Vol.14 (10), p.1131
• Main Authors: Gordillo, Oscar, Hincapie, Williams Steve, Piamba, Oscar, Olaya, Jhon, Alfonso, José Edgar, Capote, Gil, Trava-Airoldi, Vladimir
• Format: Article
• Language: English
• Subjects: AlTi coating; Aluminum; Aluminum oxide; Coatings; Corrosion and anti-corrosives; Corrosion mechanisms; Corrosion products; Corrosion resistance; Corrosion tests; Diffraction; High temperature; Lasers; Multivariate analysis; Oxidation; Physical vapor deposition; Pitting (corrosion); Raman spectroscopy; Silicon dioxide; Silicon oxides; Spatial distribution; Spectroscopic analysis; Spectrum analysis; Substrates; TiSi coating; Titanium; Titanium alloys; Titanium base alloys; Tungsten compounds; Tungsten oxides; Wear resistance; WTi coating; X ray photoelectron spectroscopy; X-rays
• ISSN: 2075-4701; 2075-4701
• DOI: 10.3390/met14101131

This study investigates the corrosion products present on TiSi, AlTi, and WTi coatings deposited onto Ti6Al4V titanium alloy substrates using the RF sputtering PVD technique. Following deposition, the coatings underwent exposure to a temperature of 600 °C for 100 h. The corroded surfaces were meticulously characterized to identify the resultant corrosion products. Utilizing scanning electron microscopy (SEM), X-ray diffraction, optical profilometry, and XPS spectroscopy, the coatings were comprehensively examined. Furthermore, Raman mapping with multivariate analysis was employed to determine the spatial distribution of oxides in the coating post-high-temperature corrosion. Additionally, XPS spectroscopy unveiled the presence of species undetected by Raman spectroscopy, such as silicon oxide SiO2, aluminum oxide Al2O3, and tungsten oxide WO2, in oxidation studies on TiSi, AlTi, and WTi coatings, corroborated by XRD analysis. The results allowed us to propose the corrosion mechanisms of these coatings and to determine that the TiSi coating exhibits a superior high-temperature corrosion response compared to the AlTi and WTi coatings. The AlTi coating experiences aluminum depletion, whereas the WTi coating shows accumulations of tungsten oxides that resemble pitting.