Electrochemical Studies on Hot Corrosion of Ni&amp;ndash;Cr&amp;ndash;Al Alloys in Molten Na&lt;SUB&gt;2&lt;/SUB&gt;SO&lt;SUB&gt;4&lt;/SUB&gt;&amp;ndash;NaCl

The present study tested the ability of a novel, facile and relatively less reported cold spray technique to develop the coatings for high temperature applications in the boiler tubes. The behaviour of the coating depends upon its microstructure, which further is decided by the coating deposition technique. The coating-substrate system material composition also affects its behaviour. For current investigation, 75Cr 3 C 2 -25(Ni-20Cr) coating is cold sprayed on Superni 75 superalloy and its behaviour is studied in a hot corrosive chlorine based aggressive environment of actual waste incinerator at 900uC. The coating microstructure obtained by cold spray process is noticed to be suitable for preventing the transport of environmental corrosive species towards the superalloy substrate.

show abstract

“…The similar dissolution of chromia layer by basic fluxing is also proposed by Hara and Shinata 20 by basic fluxing mechanism as follows: .…”

Section: Mechanismmentioning

confidence: 56%

Behaviour of cold sprayed superalloy in incinerator at 900°C

Singh

Sidhu²,

Kalsi

2015

Surface Engineering

View full text Add to dashboard Cite

show abstract

“…A negative solubility gradient of the protective oxide can be used as a criterion for the continuing hot corrosion. The fluxing mechanism in hot corrosion would lead to the re-precipitation of non-protective oxide particles [17,18].…”

Section: Discussionmentioning

confidence: 99%

Effects of Sea Salt on the Oxidation of CMSX-4® at 1100 °C

Brewster¹,

Edmonds²,

Li³

et al. 2016

Proceedings of the 13th International Symposium on Superalloys

View full text Add to dashboard Cite

Recently, a new High Temperature Environmental Testing (HTET) methodology has been described which combines cyclic oxidation with the addition of synthetic sea salt. The current investigation aims to further understand the effects of synthetic sea salt deposition on the oxidation behavior of a secondgeneration nickel-base single-crystal superalloy CMSX-4 . A series of isothermal and cyclic oxidation tests at 1100 °C were carried out on bare and salt-deposited samples. The effects of different salts and altered salt application regimes on cyclic oxidation at 1100 °C were also evaluated. Further experiments were carried out using thermo-gravimetric analysis (TGA) to study the cyclic oxidation process in greater detail for both the bare and sea salt-deposited samples. During both isothermal and cyclic oxidation, synthetic sea salt deposition generally resulted in enhanced oxidation attack compared to the bare sample. Prior oxidation to produce a stable coherent protective alumina coating loses its protective capability as soon as salt is added. Conversely, after being subjected to cyclic oxidation with salt deposition, poorer oxidation resistance was noted in subsequent cyclic oxidation without salt deposition. Cyclic oxidation investigated with TGA shows that with salt deposition, significant oxidation attack occurs within the first few cycles, after which a steady-state oxide regeneration and spallation regime was progressively attained. The effects of salt on high temperature oxidation, even at the low dosages used in the current study, are clearly critical and have lasting effects on the oxidation resistance performance on the test samples as well as components made of similar alloys; these are discussed in light of the results obtained.

show abstract

Effects of Sea Salt on the Oxidation of CMSX‐4® at 1100 °C

Pang

Pahlavanyali³

et al. 2016

Superalloys 2016

View full text Add to dashboard Cite

Electrochemical Studies on Hot Corrosion of Ni–Cr–Al Alloys in Molten Na<SUB>2</SUB>SO<SUB>4</SUB>–NaCl

Cited by 9 publications

References 15 publications

Behaviour of cold sprayed superalloy in incinerator at 900°C

Behaviour of cold sprayed superalloy in incinerator at 900°C

Effects of Sea Salt on the Oxidation of CMSX-4® at 1100 °C

Effects of Sea Salt on the Oxidation of CMSX‐4® at 1100 °C

Contact Info

Product

Resources

About