Microstructural, mechanical properties and corrosion behavior of plasma sprayed NiCrAlY/nano-YSZ duplex coating on Mg–1.2Ca–3Zn alloy. Issue 10 (December 2015)

• Record Type: Journal Article
• Authors: Bakhsheshi-Rad, H.R.; Hamzah, E.; Ismail, A.F.; Daroonparvar, M.; Kasiri-Asgarani, M.; Jabbarzare, S.; Medraj, M.
• Is Part Of: Ceramics international. Volume 41:Issue 10(2015)Part B
• Page Start: 15272
• Page End: 15277
• Publication Date: 2015-12
• Subjects: Magnesium alloy -- Plasma spray -- Yttria stabilized zirconia -- Corrosion behavior; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.08.025
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In this study, microstructural evolution, mechanical properties and corrosion behavior of plasma sprayed NiCrAlY/nano-yttria stabilized zirconia (nano-YSZ) dual-layered coating on Mg–1.2Ca–3Zn alloy were investigated. NiCrAlY underlayer is composed of large amount of porosities and micro-cracks with thickness around 80–90 μm. However, nano-YSZ overlayer shows bimodal microstructure consisting of columnar grains and some partially molten parts of the nanostructured powders with thickness around 270–300 μm. The microhardness of dual-layered NiCrAlY/nano-YSZ coating is significantly higher than that of single-layered NiCrAlY. Despite that, the bonding strength of dual-layered coating is slightly higher than single-layered plasma sprayed coating. Results also showed that both single-layer NiCrAlY and dual-layer NiCrAlY/nano-YSZ coatings decreased the corrosion current density of Mg alloy from 217.1 μA/cm 2 to 114.5 and 82.4 µA/cm 2, respectively.