A new insight into the NaCl-induced hot corrosion mechanism of TiN coatings at 500 °C. (September 2020)

• Record Type: Journal Article
• Authors: Li, Rongzhi; Wang, Shunhua; Zhou, Dapeng; Pu, Jibin; Yu, Miao; Guo, Wuming
• Is Part Of: Corrosion science. Volume 174(2020)
• Publication Date: 2020-09
• Subjects: A. Titanium alloy -- A. TiN coating -- B. TEM -- C. Salt spray -- C. Hot corrosion; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2020.108794
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: The hot corrosion process of the TiN coating was significantly increased with present of salt at 500 °C. Different NaCl applying methods could lead to different failure modes of TiN coatings. The NaCl solution infiltrated into the TiN coatings through the defects and accelerated the corrosion of the coatings. Abstract: The NaCl-induced hot corrosion behaviors of TiN coatings at 500 °C were investigated. The results showed that NaCl could accelerate hot corrosion of TiN coatings, but NaCl applying method has different effects on the failure of the coating. TiN coatings after salt spray (3.5 wt.% NaCl solution) showed more severe hot corrosion and spallation than the ones deposited with solid salt. It was found NaCl solution infiltrated into the coatings through defects, thus forming Nax Tiy Oz products inside the coatings at 500 °C. These corrosion products with a larger volume introduced stresses into the coatings, leading to the spallation of the coatings.