High-temperature corrosion behavior of selected thermally sprayed coatings in corrosive aggressive environment

0511598 - ÚFP 2020 RIV GB eng J - Článek v odborném periodiku
Česánek, Z. - Houdková, Š. - Lukáč, František
High-temperature corrosion behavior of selected thermally sprayed coatings in corrosive aggressive environment.
Materials Research Express. Roč. 6, č. 1 (2019), č. článku 016426. E-ISSN 2053-1591
Institucionální podpora: RVO:61389021
Klíčová slova: heat-treatment * resistance * thermally sprayed coating * corrosion resistance * molten salts * Cr3C2-25% NiCr * stellite 6 * hastelloy C-276
Obor OECD: Materials engineering
Impakt faktor: 1.929, rok: 2019
Způsob publikování: Omezený přístup
https://iopscience.iop.org/article/10.1088/2053-1591/aae956

The aim of this paper is to evaluate and compare the corrosion resistance of Hastelloy C-276 coating with Stellite 6 and Cr3C2%25% NiCr coatings. The coatings were deposited using HP/HVOF (High Pressure/High Velocity Oxygen Fuel) thermal spraying technology. The corrosion test was conducted in the corrosive-aggressive environment of molten salts mixture in the composition of 40% Na2SO4-60% V2O5, simulating the corrosion environment of boilers for residual fuel oils. The corrosion test under cyclic conditions included 50 cycles at the temperature of 750 degrees C and subsequent cooling at the room temperature for 20 min. The corroded specimens were analyzed using scanning electron microscope (SEM) and elemental analysis (EDS). In comparison with Cr3C225% NiCr coating, both Stellite 6 and Hastelloy C-276 coatings provided the substrate material with sufficient protection against high-temperature corrosion. The corrosion mechanism of Hastelloy C-276 coating was based on the formation of protective oxide layer which prevented further penetration of corrosive media. Stellite 6 coating exhibited the corrosion attack along splat boundaries resulting in spat delaminating into the build-up. The corrosion mechanism of Cr3C2-25% NiCr coating included the attack on NiCr matrix resulting in gradual separation of carbide phases into the corrosive environment.
Trvalý link: http://hdl.handle.net/11104/0301831