Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings
Tribological coatings are widely used in industry, particularly when the conventional oil lubrication of sliding surfaces has to be replaced by maintenance-free contacts. This work studies the tribological performance of waterborne tribological coatings based on three binders of the polyaryletherket...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-09-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/14/19/4008 |
| _version_ | 1797477304723570688 |
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| author | Judith M. Pedroso Marco Enger Pedro Bandeira Fernão D. Magalhães |
| author_facet | Judith M. Pedroso Marco Enger Pedro Bandeira Fernão D. Magalhães |
| author_sort | Judith M. Pedroso |
| collection | DOAJ |
| description | Tribological coatings are widely used in industry, particularly when the conventional oil lubrication of sliding surfaces has to be replaced by maintenance-free contacts. This work studies the tribological performance of waterborne tribological coatings based on three binders of the polyaryletherketone (PAEK) family: polyetherketone (PEK), PEEK, and polyetherketoneketone (PEKK). Even though PEEK is a well-known commercial solution for this type of tribological coatings, PEK and PEKK have never been studied in such a context. PTFE particles were added to all coatings as a solid lubricant. High thermal resistance of the binder materials was confirmed, with decomposition starting above 550 °C, under either N<sub>2</sub> or O<sub>2</sub> atmosphere. XRD analysis showed that PEK and PEEK are semi-crystalline after being subjected to the coating curing conditions, while PEKK is amorphous. The coatings were successfully applied with thicknesses of 20–30 µm. Tribological measurements showed that the PEK-based coating possesses a coefficient of friction (COF) of 0.08 under high load and pressure conditions (hertzian point contact), which is lower than the reference PEEK-based coating (around 0.11). The PEKK-based coating showed an impressive wear resistance with almost no wear measured compared to the 105 µm wear obtained for PEEK-based coating, while showing a similar COF. These results suggest that PEK and PEKK seem to be interesting alternatives to PEEK and should be further studied for use in tribological coatings. |
| first_indexed | 2024-03-09T21:16:41Z |
| format | Article |
| id | doaj.art-2aba4ddceb694f5b8a7a2730a67c82ab |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-09T21:16:41Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-2aba4ddceb694f5b8a7a2730a67c82ab2023-11-23T21:32:44ZengMDPI AGPolymers2073-43602022-09-011419400810.3390/polym14194008Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological CoatingsJudith M. Pedroso0Marco Enger1Pedro Bandeira2Fernão D. Magalhães3GGB Bearings Technology Porto, Rua Dr. Júlio de Matos, 828/882, 4200-355 Porto, PortugalGGB Bearings Technology GmbH, 74078 Heilbronn, GermanyGGB Bearings Technology Porto, Rua Dr. Júlio de Matos, 828/882, 4200-355 Porto, PortugalLEPABE— Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, PortugalTribological coatings are widely used in industry, particularly when the conventional oil lubrication of sliding surfaces has to be replaced by maintenance-free contacts. This work studies the tribological performance of waterborne tribological coatings based on three binders of the polyaryletherketone (PAEK) family: polyetherketone (PEK), PEEK, and polyetherketoneketone (PEKK). Even though PEEK is a well-known commercial solution for this type of tribological coatings, PEK and PEKK have never been studied in such a context. PTFE particles were added to all coatings as a solid lubricant. High thermal resistance of the binder materials was confirmed, with decomposition starting above 550 °C, under either N<sub>2</sub> or O<sub>2</sub> atmosphere. XRD analysis showed that PEK and PEEK are semi-crystalline after being subjected to the coating curing conditions, while PEKK is amorphous. The coatings were successfully applied with thicknesses of 20–30 µm. Tribological measurements showed that the PEK-based coating possesses a coefficient of friction (COF) of 0.08 under high load and pressure conditions (hertzian point contact), which is lower than the reference PEEK-based coating (around 0.11). The PEKK-based coating showed an impressive wear resistance with almost no wear measured compared to the 105 µm wear obtained for PEEK-based coating, while showing a similar COF. These results suggest that PEK and PEKK seem to be interesting alternatives to PEEK and should be further studied for use in tribological coatings.https://www.mdpi.com/2073-4360/14/19/4008coatingPEEKPEKPEKKPTFEtribology |
| spellingShingle | Judith M. Pedroso Marco Enger Pedro Bandeira Fernão D. Magalhães Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings Polymers coating PEEK PEK PEKK PTFE tribology |
| title | Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings |
| title_full | Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings |
| title_fullStr | Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings |
| title_full_unstemmed | Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings |
| title_short | Comparative Study of Friction and Wear Performance of PEK, PEEK and PEKK Binders in Tribological Coatings |
| title_sort | comparative study of friction and wear performance of pek peek and pekk binders in tribological coatings |
| topic | coating PEEK PEK PEKK PTFE tribology |
| url | https://www.mdpi.com/2073-4360/14/19/4008 |
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