Microstructure and corrosion behavior of HVAF-sprayed Fe-based composite coatings doped TiB2 and CNTs. (November 2022)

• Record Type: Journal Article
• Authors: Liu, Xiaoqing; Zeng, Dechang; Wu, Yaosha; Zheng, Zhigang; Qiu, Zhaoguo
• Is Part Of: Corrosion science. Volume 208(2022)
• Publication Date: 2022-11
• Subjects: HVAF spraying -- Fe-based coating -- Carbon nanotube -- Corrosion resistance; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110629
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: Fe-based composite coating doped well-dispersed titanium boride (TiB2 ) and carbon nanotubes (CNTs) were successfully fabricated via high velocity air fuel (HVAF) spraying. The microstructure and corrosion behavior of Fe-based metallic, Fe-TiB2 cermet and Fe/(TiB2 -CNTs) coatings were comparatively investigated. It is found that doping TiB2, especially further doping 2.5 vol% CNTs could remarkably render the coatings lower porosity, favorable microstructure, superior hydrophobicity and then enhanced corrosion resistance. Thanks to the densest microstructure and the formation of passive films, pitting instead of severe etch groove in TiB2 -Fe interface inside splats and inter-splats was the main corrosion mechanism of the Fe/(TiB2 -CNTs) coating. Graphical Abstract: ga1 Highlights: CNT and TiB2 were firstly attempted to dope into the HVAF-sprayed Fe-based coating. Doping TiB2, especially CNTs render the coatings lower porosity and favorable microstructure. Best enhancement in corrosion resistance was obtained via simultaneously doping TiB2 and CNTs.