Interfacial bonding of low-pressure plasma-sprayed Fe-based amorphous coating on 8090 Al–Li alloy

ABSTRACT

Fe-based amorphous coatings (AMC) are deposited on 8090 Al–Li alloy using low-pressure plasma spraying. Coating’s microstructure and interfacial characteristics are investigated. The coating is mainly amorphous in structure. Some crystalline phases were observed between the two splats. The corrosion current density of this coating is two orders of magnitude less compared to 8090. The coating has high density as the average porosity is less than 0.5%. Because of partial melting and quick cooling of the 8090 alloy in the process of molten droplets deposition, there is an amorphous transition zone formed at the interface of AMC/8090 Al–Li alloy, which indicates localized metallurgical bonding. In electrochemical testing, the coating shows an obvious passivation tendency, and crystallization between splats is the main cause of corrosion. Owing to the low oxygen content, the coating exhibits excellent wear resistance.

KEYWORDS:

• Low-pressure plasma spraying
• Fe-based amorphous coating
• Al–Li alloy
• metallurgical bonding
• high density

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is supported by the National Natural Science Foundation of China [grant number 51971020 ]; Project of Chinese Ministry of Armament [grant number 41423060313]; Fund Project of Key Laboratory of Forming and Joining Technology for Aviation Components [grant number HKGJ-2002]; Jiangxi Provincial High-level and High-skilled Leading Talents Training Project [117002232160].