A novel approach to incorporate graphene nanoplatelets to Cr2O3 for low-wear coatings

• Published in: Materials letters Vol. 276; p. 128283
• Main Authors: Venturi, F., Pulsford, J., Hussain, T.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-10-2020; Elsevier BV
• Subjects: Aluminum oxide; Ceramics; Chromia; Chromium oxides; Coatings; Coefficient of friction; Corrosion resistance; Corrosive wear; Graphene; Graphene nanoplatelets; Materials science; Microhardness; Nanocomposites; Oxy-fuel; Stainless steels; Substrates; Tribology; Wear; Wear rate; Wear resistance; Graphene nanoplatelets; Ceramics; Nanocomposites; Wear; Chromia; Tribology
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2020.128283

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•Chromia/graphene nanoplatelets coatings are deposited with suspension thermal spray.•The structural integrity of graphene nanoplatelets is preserved upon spray.•Graphene nanoplatelets lower the coefficient of friction against alumina by 15%.•Specific wear rate is also lowered by 20% (coating) and 70% (counterbody).
Cr2O3 (chromia) coatings have been widely used in wear and corrosion resistant applications thanks to their good tribomechanical properties, and graphene nanoplatelets (GNPs) have been employed as nanofillers to further improve these properties. In this work, we propose a process to deposit chromia/GNPs composite coatings on stainless steel substrates using Suspension High Velocity Oxy-Fuel (S-HVOF) thermal spray. The coating showed good microhardness, with successful incorporation of GNPs showing no or minor spray-induced degradation. Compared to a chromia-only coating, the tribological performance improved: both coating and alumina counterbody specific wear rates lowered by 20 and 70% respectively and coefficient of friction decreased by 15%. This study shows a non-expensive and simple method to incorporate GNPs to improve material performance in large scale.