Hot corrosion behavior of solution precursor and atmospheric plasma sprayed thermal barrier coatings. (September 2015)

• Record Type: Journal Article
• Authors: Ajay, A.; Raja, V.S.; Sivakumar, G.; Joshi, S.V.
• Is Part Of: Corrosion science. Volume 98(2015)
• Page Start: 271
• Page End: 279
• Publication Date: 2015-09
• Subjects: C. Hot corrosion -- A. Ceramic -- B. SEM -- B. XRD -- A. Superalloys; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2015.05.034
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: Prepared atmospheric and solution precursor plasma spray thermal barrier coatings. Hot corrosion studies were conducted in chlorides and vanadates. Solution precursor plasma spray coatings showed inferior corrosion resistance. Vertical cracks are detrimental to hot corrosion resistance. Abstract: Hot corrosion behavior of solution precursor plasma spray (SPPS) thermal barrier coating (TBC) in molten salt mixtures of 90 wt.% Na2 SO4 + 5 wt.% V2 O5 + 5 wt.% NaCl and 50 wt.% Na2 SO4 + 50 wt.% V2 O5 at 900 °C is compared vis-à-vis atmospheric plasma spray (APS) coating. APS TBCs show better hot corrosion resistance than SPPS TBCs in both the salt mixtures. The vertical cracks in SPPS coatings, meant for strain tolerance and high thermal cycling life, serve as channels for transporting salts across the coating to bond coat/top coat interface and accelerate failure.