Microstructure evolution and hot corrosion behavior of Zr-Y modified silicide coating prepared by two-step process. (1st August 2019)

• Record Type: Journal Article
• Authors: He, Jiahua; Guo, Xiping; Qiao, Yanqiang
• Is Part Of: Corrosion science. Volume 156(2019)
• Page Start: 44
• Page End: 57
• Publication Date: 2019-08-01
• Subjects: A. Metal coatings -- A. Molten salts -- B. EPMA -- C. Hot corrosion; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2019.05.010
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: Zr-Y modified silicide coatings were successfully prepared by a two-step process. The microstructural evolution of the two-step coating was detailed investigated. The coating could protect the substrate from hot corrosion at 900 °C for 100 h. The released Cl2, sulfur from molten salts could accelerate oxidation of the coating. Abstract: Zr-Y modified silicide coating on the Nb-Si based ultrahigh temperature alloy is prepared by firstly magnetron sputtering Ti-5Al-10Nb-2Zr (at.%) alloy film and then Si-Y co-deposition. The coating is mainly composed of a TiSi2 outer layer, a relatively thick (Nb, X)Si2 inner layer and a thin transitional layer. The mass gain of the bare alloy, simple Si-Y coating and two-step coating is 97, 7.3 and 4.1 mg/cm 2 respectively after hot corrosion at 900 °C for 100 h in Na2 SO4 +NaCl molten salts. The hot corrosion mechanism of the coating has been revealed.