Microstructure and tribological properties of TiCN-Al2O3 composite coatings fabricated by reactive plasma spraying. (January 2018)

• Record Type: Journal Article
• Authors: Qin, Y.F.; Zhu, L.Y.; He, J.N.; Yin, F.X.; Nan, Z.S.; Zhao, L.J.
• Is Part Of: Vacuum. Volume 147(2018)
• Page Start: 149
• Page End: 157
• Publication Date: 2018-01
• Subjects: TiCN-Al2O3 composite coating -- Reactive plasma spraying -- Microstructure -- Tribological properties -- Oxidation behavior; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2017.10.034
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: In this paper, TiCN-Al2 O3 composite coatings were fabricated by reactive plasma spraying (RPS). The influences of Al2 O3 content on the microstructure, phase and composition of composite coatings were investigated. The Vickers microhardness of coatings was tested and the corresponding Weibull distributions were also analyzed. In addition, oxidized and tribological properties of composite coatings were investigated. Results show that all the composite coatings consist of TiC0.7 N0.3, TiO2, γ-Al2 O3, few α-Al2 O3 and/or residual graphite and the amount of TiC0.7 N0.3 decreases with the increase of Al2 O3 content. Al2 O3 particles preferentially distribute at inter-lamellar gaps to improve the microstructural compactness, while a loose structure is formed as the increase of Al2 O3 particles. Weibull distribution of Vickers microhardness of all the coatings shows apparent scattering characteristic, while a relatively even distribution is obtained for the coating with 10 wt% Al2 O3 . Furthermore, the coating with 10 wt% Al2 O3 exhibits a better oxidation resistance and wear resistance due to the dense microstructure. Highlights: All the coatings consist of TiC0.7 N0.3, TiO2, γ-Al2 O3, few α-Al2 O3 and/or residual graphite. The Al2 O3 particles will fill into inter-layer gap, leading to enhancement of compactness and performances of coating. The reunion of brittle Al2 O3 particles in interlayer gap is unwanted as the increasing Al2 O3 content. The coating with 10 wt% Al2 O3 exhibits improved performances due to its dense structure. The wear mechanism of coatings is abrasive wear and fatigue wear accompanied with tribo-oxidation wear.