Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis

For rapid surface engineering of Cr-containing alloys by low-temperature nitrocarburization, we introduce a process based on pyrolysis of solid reagents, e.g., urea, performed in an evacuated closed vessel. Upon heating to temperatures high enough for rapid diffusion of interstitial solute, but low...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Cyprian Illing, Zhe Ren, Anna Agaponova, Arthur Heuer, Frank Ernst
Formato:	article
Lenguaje:	EN
Publicado:	MDPI AG 2021
Materias:	alloy surface engineering colossal supersaturation nitrocarburization reagent pyrolysis auto-catalytic effect Mining engineering. Metallurgy TN1-997
Acceso en línea:	https://doaj.org/article/c4fe61e3102242838383225892eaf962
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:c4fe61e3102242838383225892eaf962
record_format	dspace
spelling	oai:doaj.org-article:c4fe61e3102242838383225892eaf9622021-11-25T18:21:45ZRapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis10.3390/met111117642075-4701https://doaj.org/article/c4fe61e3102242838383225892eaf9622021-11-01T00:00:00Zhttps://www.mdpi.com/2075-4701/11/11/1764https://doaj.org/toc/2075-4701For rapid surface engineering of Cr-containing alloys by low-temperature nitrocarburization, we introduce a process based on pyrolysis of solid reagents, e.g., urea, performed in an evacuated closed vessel. Upon heating to temperatures high enough for rapid diffusion of interstitial solute, but low enough to avoid second-phase precipitation, the reagent is pyrolyzed to a gas atmosphere containing molecules that (i) activate the alloy surface by stripping away the passivating Cr<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>O<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>3</mn></msub></semantics></math></inline-formula>-rich surface film (diffusion barrier) and (ii) rapidly infuse carbon and nitrogen into the alloy. We demonstrate quantitatively that this method can generate a subsurface zone with concentrated carbon and nitrogen comparable to what can be accomplished by established (e.g., gas-phase- or plasma-based) methods, but with significantly reduced processing time. As another important difference to established gas-phase processing, the interaction of gas molecules with the alloy surface can have auto-catalytic effects by altering the gas composition in a way that accelerates solute infusion by providing a high activity of HNCO. The new method lends itself to rapid experimentation with a minimum of laboratory equipment.Cyprian IllingZhe RenAnna AgaponovaArthur HeuerFrank ErnstMDPI AGarticlealloy surface engineeringcolossal supersaturationnitrocarburizationreagent pyrolysisauto-catalytic effectMining engineering. MetallurgyTN1-997ENMetals, Vol 11, Iss 1764, p 1764 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	alloy surface engineering colossal supersaturation nitrocarburization reagent pyrolysis auto-catalytic effect Mining engineering. Metallurgy TN1-997
spellingShingle	alloy surface engineering colossal supersaturation nitrocarburization reagent pyrolysis auto-catalytic effect Mining engineering. Metallurgy TN1-997 Cyprian Illing Zhe Ren Anna Agaponova Arthur Heuer Frank Ernst Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis
description	For rapid surface engineering of Cr-containing alloys by low-temperature nitrocarburization, we introduce a process based on pyrolysis of solid reagents, e.g., urea, performed in an evacuated closed vessel. Upon heating to temperatures high enough for rapid diffusion of interstitial solute, but low enough to avoid second-phase precipitation, the reagent is pyrolyzed to a gas atmosphere containing molecules that (i) activate the alloy surface by stripping away the passivating Cr<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>O<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>3</mn></msub></semantics></math></inline-formula>-rich surface film (diffusion barrier) and (ii) rapidly infuse carbon and nitrogen into the alloy. We demonstrate quantitatively that this method can generate a subsurface zone with concentrated carbon and nitrogen comparable to what can be accomplished by established (e.g., gas-phase- or plasma-based) methods, but with significantly reduced processing time. As another important difference to established gas-phase processing, the interaction of gas molecules with the alloy surface can have auto-catalytic effects by altering the gas composition in a way that accelerates solute infusion by providing a high activity of HNCO. The new method lends itself to rapid experimentation with a minimum of laboratory equipment.
format	article
author	Cyprian Illing Zhe Ren Anna Agaponova Arthur Heuer Frank Ernst
author_facet	Cyprian Illing Zhe Ren Anna Agaponova Arthur Heuer Frank Ernst
author_sort	Cyprian Illing
title	Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis
title_short	Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis
title_full	Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis
title_fullStr	Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis
title_full_unstemmed	Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis
title_sort	rapid alloy surface engineering through closed-vessel reagent pyrolysis
publisher	MDPI AG
publishDate	2021
url	https://doaj.org/article/c4fe61e3102242838383225892eaf962
work_keys_str_mv	AT cyprianilling rapidalloysurfaceengineeringthroughclosedvesselreagentpyrolysis AT zheren rapidalloysurfaceengineeringthroughclosedvesselreagentpyrolysis AT annaagaponova rapidalloysurfaceengineeringthroughclosedvesselreagentpyrolysis AT arthurheuer rapidalloysurfaceengineeringthroughclosedvesselreagentpyrolysis AT frankernst rapidalloysurfaceengineeringthroughclosedvesselreagentpyrolysis
_version_	1718411283835912192

Rapid Alloy Surface Engineering through Closed-Vessel Reagent Pyrolysis

Ejemplares similares