Microstructural study of the NbC to G-phase transformation in HP-Nb alloysShow others and affiliations
2020 (English)In: Materialia, E-ISSN 2589-1529, Vol. 9, article id 100593Article in journal (Refereed) Published
Abstract [en]
The microstructure of a centrifugally cast HP alloy was studied in its as-received state and after ageing at 900 °C. A multi-scale approach combining X Ray Diffraction (XRD), advanced electron microscopy modes (scanning and transmission electron microscopies (SEM, TEM), together with focused ion beam/SEM nanotomography (FIB-nt)) has been carried out to characterize the evolution of niobium carbides during ageing. After thermal treatment, the carbides exhibit a complex microstructure, consisting of a core of untransformed NbC, an intermediate layer of G-phase (Ni16Nb6Si7) with embedded nanometric titanium carbide precipitates, and an outer shell of alternating chromium carbides Cr23C6 and G-phase. A simple diffusion model was used to explain the faster external growth of G-phase compared to the internal NbC dissolution, and to determine a diffusion coefficient of niobium in the G-phase at 900 °C.
Place, publisher, year, edition, pages
Elsevier B.V. , 2020. Vol. 9, article id 100593
Keywords [en]
Advanced material characterization, Ageing, G-phase, HP-Nb alloy, Microstructure, NbC, Carbides, Chromium compounds, Diffusion, Ion beams, Nickel compounds, Niobium compounds, Scanning electron microscopy, Silicon compounds, Titanium carbide, Transmission electron microscopy, Advanced materials, Carbide precipitate, Complex microstructures, Multi-scale approaches, Nb alloys, Scanning and transmission electron microscopy, Niobium alloys
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-50114DOI: 10.1016/j.mtla.2020.100593Scopus ID: 2-s2.0-85078161560OAI: oai:DiVA.org:ri-50114DiVA, id: diva2:1497176
Note
Funding details: Association Nationale de la Recherche et de la Technologie, ANRT, 2015/0205; Funding details: Association Nationale de la Recherche et de la Technologie, ANRT; Funding text 1: This work was financially supported by the ANRT (Association Nationale de la Recherche et de la Technologie) through Project 2015/0205. Thanks are due to the Clym platform ( www.clym.fr ) for access to the FIB-SEM microscope. This research has benefited from characterization equipment of the Grenoble INP - CMTC platform supported by the Centre of Excellence of Multifunctional Architectured Materials ``CEMAM'' n°ANR-10-LABX-44-01 funded by the Investments for the Future programme
2020-11-042020-11-042023-03-28Bibliographically approved