• Marques, Francisco Das Chagas
• Marcondes, Andre Ricardo
• Macário, P. F.
• Vieira, Angela Aparecida Moraes
• Macêdo Fechine, Guilhermino José
• Hahn Da Silveira, Carolina

Abstract

<jats:p>This study presents an innovative dual-layer coating approach integrating titanium dioxide (TiO2) onto diamond-like carbon (DLC)-coated 316L stainless steel. The combination of PECVD-deposited DLC and ALD-deposited TiO2 aims to preserve the inherent tribological properties of DLC while mitigating UV-induced degradation. By leveraging the ability of TiO2 to absorb, reflect, and scatter UV light, this dual-layer strategy significantly enhances the durability of DLC coatings in radiation-prone environments. The effects of accelerated aging through UV exposure on DLC and DLC/TiO2 films were evaluated using an Accelerated Weathering Tester. Comprehensive analyses were conducted to assess the structural and mechanical properties before and after UV exposure, including Raman spectroscopy, profilometry, SEM, EDS, nanoindentation, and tribometry. The results demonstrate that the TiO2 layer effectively mitigates UV-induced damage, preserving the DLC film’s integrity and tribological performance even after 408 h of UV aging. Specifically, the DLC/TiO2 coatings maintained lower roughness, higher hardness, and better adhesion than DLC-only coatings under identical conditions. This research significantly advances protective coating technology by enhancing the durability and performance of DLC films, particularly in aerospace and other demanding industries where exposure to UV radiation is a critical concern.</jats:p>

Topics

• impedance spectroscopy
• Carbon
• stainless steel
• scanning electron microscopy
• hardness
• nanoindentation
• titanium
• aging
• Energy-dispersive X-ray spectroscopy
• Raman spectroscopy
• aging
• profilometry