Structural changes of thermal sprayed graphene nano platelets film into amorphous carbon under sliding wear

Derelizade, K.; Venturi, F.; Wellman, R. G.; Khlobystov, A.; Hussain, T.

Abstract

© 2020 The Authors Graphene has become a promising candidate to protect surfaces against friction due to its strength and lubricating ability. In this study, graphene nano platelets (GNP) thin films have been deposited onto stainless steel substrates by axially injecting GNP suspension through high velocity oxy fuel thermal spray gun. The tribological performance of the films under dry sliding wear was investigated through unlubricated ball on disc sliding wear test against a sintered alumina counter body ball under 5 N load. The understanding of the behaviour of the GNPs under sliding wear will be useful for improving the performance of graphene-based coatings which are in demand for wear resistant applications. A film was deposited showing significant improvements in friction with coefficient of friction value reduced by 7 times compared to uncoated stainless steel, even for a discontinuous film. A morphological analysis shows sliding wear led to change in particle shape from angular flakes into randomly oriented circles. Interatomic bonding and structural analysis performed reveals oxidation defect formations during wear test. Structural degradation and oxidation of GNPs during the process led to formation of amorphous carbon from graphene. Amorphous carbon formation reduces the lubricating ability and strength of the film, leading to failure.

Citation

Derelizade, K., Venturi, F., Wellman, R. G., Khlobystov, A., & Hussain, T. (2020). Structural changes of thermal sprayed graphene nano platelets film into amorphous carbon under sliding wear. Applied Surface Science, 528, https://doi.org/10.1016/j.apsusc.2020.146315

• Journal Article Type: Article
• Acceptance Date: Apr 2, 2020
• Online Publication Date: Jun 21, 2020
• Publication Date: Oct 30, 2020
• Deposit Date: Jun 24, 2020
• Publicly Available Date: Jun 22, 2021
• Journal: Applied Surface Science
• Print ISSN: 0169-4332
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 528
• Article Number: 146315
• DOI: https://doi.org/10.1016/j.apsusc.2020.146315
• Keywords: Surfaces, Coatings and Films
• Public URL: https://nottingham-repository.worktribe.com/output/4706812
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0169433220310710?via%3Dihub