Effects of Cr on NiAl (β′) Precipitation in Ferritic Fe-Ni-Al AlloysShow others and affiliations
2021 (English)In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 52, no 9, p. 3777-3787Article in journal (Refereed) Published
Abstract [en]
NiAl (β′)-strengthened ferritic alloys are promising candidates for high-temperature applications. They present a coherent precipitate–matrix interface and are usually alloyed with 10 wt pct Cr to improve corrosion resistance and provide solid solution strengthening. In this work, the effects of Cr content on the precipitation of β′ in Fe-Ni-Al ferritic alloys are studied using dilatometric analysis during continuous heating and cooling. The dilatometric data are correlated with microstructural observations, X-ray diffraction, and thermodynamic calculations. Additionally, isothermally annealed diffusion couples are used for determining the β′ phase stability during isothermal conditions. Results indicate that an increase in Cr shifts the dissolution of β′ to higher temperatures and the Curie point to lower values. Furthermore, the coarsening rate of the β′ phase increases with the concentration of Cr. The addition of Cr implies a tradeoff between beneficial aspects like increased corrosion resistance and extended β′ stability range against the partial loss of coherency and a higher coarsening rate. The agreement between thermodynamic calculations and the experimental data provides a useful insight for further materials development.
Place, publisher, year, edition, pages
Springer, 2021. Vol. 52, no 9, p. 3777-3787
National Category
Metallurgy and Metallic Materials
Research subject
Engineering Materials
Identifiers
URN: urn:nbn:se:ltu:diva-85529DOI: 10.1007/s11661-021-06338-xISI: 000659803700001Scopus ID: 2-s2.0-85107483536OAI: oai:DiVA.org:ltu-85529DiVA, id: diva2:1567933
Note
Validerad;2021;Nivå 2;2021-08-12 (alebob);
Finansiär: CONACYT (222459); Österreichischer Austauschdienst; Bundesministerium für Bildung, Wissenschaft und Forschung; GAID; IPN-SIP-BEIFI
2021-06-172021-06-172023-09-05Bibliographically approved