The purpose of this study is to evaluate the thermal and tribological performance of silica and alumina sol–gel coatings under combined thermal and structural loading. Using finite element analysis (FEA) and experimental data from a pin-on-disc (POD) tribometer, the study assesses contact parameters such as frictional stress, contact pressure and heat flux at elevated temperatures. The goal is to understand the effectiveness of these coatings in enhancing wear resistance and reducing friction, providing insights for improving material performance in high-temperature applications.
The study combines experimental and numerical approaches to evaluate coated samples. Silica and alumina coatings were applied on aluminium alloy substrates using the sol–gel dip-coating method. Tribological tests were conducted using a POD tribometer at elevated temperatures against an EN31 hardened disc to measure coefficient of friction (COF) and volumetric wear loss (VWL). FEA was performed using ANSYS Workbench with static structural and steady-state thermal templates to simulate contact pressure, frictional stress and heat flux. Scanning electron microscope (SEM) and energy dissipation X-ray spectroscopy (EDAX) analyses were conducted to examine surface morphology and elemental composition of uncoated and coated samples before and after testing.
The study revealed that both silica and alumina coatings significantly improved tribological performance at elevated temperatures. Coated samples showed reduced COF and lower (VWL) compared to uncoated samples. FEA results indicated decreased contact pressure, frictional stress and heat flux in coated specimens, confirming better thermal stability. SEM analysis showed smoother wear tracks on coated surfaces, while EDAX confirmed uniform coating distribution. Among the coatings, alumina demonstrated slightly superior performance. Overall, the findings highlight the effectiveness of sol–gel coatings in enhancing wear resistance and thermal performance under combined loading conditions.
This study uniquely integrates experimental tribological testing with FEA to evaluate material performance under combined thermal and structural loading. By focusing on sol–gel coated silica and alumina surfaces, it provides a comprehensive understanding of how such coatings influence wear behaviour and thermal resistance at elevated temperatures. The research offers valuable insights for industries operating in high-temperature environments, demonstrating how advanced coatings can extend component life and reduce energy loss due to friction. The dual approach enhances the reliability of the findings and contributes to the development of more durable and efficient material systems.
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2025-0236/
