Incorporation of graphene nano platelets in suspension plasma sprayed alumina coatings for improved tribological propertiesShow others and affiliations
2021 (English)In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 570, article id 151227Article in journal (Refereed) Published
Abstract [en]
Graphene possesses high fracture toughness and excellent lubrication properties, which can be exploited to enhance tribological performance of coating systems utilized to combat wear. In this work, suspension plasma spray (SPS) process was employed to deposit a composite, graphene nano-platelets (GNP) incorporated alumina coating. For comparison, monolithic alumina was also deposited utilizing identical spray conditions. The as-deposited coatings were characterized in detail for their microstructure, porosity content, hardness, fracture toughness and phase composition. Raman analysis of the as-deposited composite coating confirmed retention of GNP. The composite coating also showed good microstructural integrity, comparable porosity, higher fracture toughness and similar alumina phase composition as the monolithic alumina coating. The as-deposited coatings were subjected to dry sliding wear tests. The GNP incorporated composite coating showed lower CoF and lower specific wear rate than the pure alumina coating. Additionally, the counter surface also showed a lower wear rate in case of the composite coating. Post-wear analysis performed by SEM/EDS showed differences in the coating wear track and in the ball wear track of monolithic and composite coatings. Furthermore, Raman analysis in the wear track of composite coating confirmed the presence of GNP. The micro-indentation and wear test results indicate that the presence of GNP in the composite coating aided in improving fracture toughness, lowering CoF and specific wear rate compared to the monolithic coating. Results from this work demonstrated retention of GNP in an SPS processed coating, which can be further exploited to design superior wear-resistant coatings.
Place, publisher, year, edition, pages
Elsevier B.V. , 2021. Vol. 570, article id 151227
Keywords [en]
Alumina; Composite coatings; Fracture toughness; Graphene; Phase composition; Plasma jets; Plasma spraying; Platelets; Porosity; Sprayed coatings; Tribology; Wear of materials, Alumina coating; Composites coating; Deposited coatings; Dry sliding wear test; Graphene nano-platelet; Monolithic alumina; Nanoplatelet; Raman analysis; Suspension plasma sprays; Wear tracks, Aluminum oxide
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology
Identifiers
URN: urn:nbn:se:hv:diva-17510DOI: 10.1016/j.apsusc.2021.151227ISI: 000724554400007Scopus ID: 2-s2.0-85114835136OAI: oai:DiVA.org:hv-17510DiVA, id: diva2:1599213
Funder
Vinnova
Note
The authors gratefully acknowledge financial support received from the national Strategic Innovation Programme for graphene, SIO Grafen, supporting the industrial graphene development in Sweden. The programme is supported by the Swedish government agencies Vinnova (Sweden’s Innovation Agency), the Swedish Energy Agency and the Swedish Research Council Formas. The project grant nr. is Dnr 2018-03315. We also thank Mr. Sven Forsberg, 2DFab AB, Sweden, for providing the water-based GNP suspension.
2021-09-302021-09-302022-04-04Bibliographically approved