Small-angle scattering enables the extraction of precise, quantitative information about nano-scale precipitate microstructures. It can be used with X-rays (SAXS) or neutrons (SANS). This paper presents simple methods for extracting information on the precipitate size and volume fraction from SAS spectra. The various possibilities for obtaining precipitate size are reviewed, and the meaning of their differences is discussed. Examples of applications for complex precipitate microstructure measurements are given in the following areas: kinetic in-situ measurements in Fe–Cu and Fe–Nb–C alloys, non-stoichiometric precipitation in an Al–Zn–Mg–Cu alloy studied by anomalous SAXS (ASAXS), and precipitation mapping in weld cross-sections.
La technique de diffusion aux petits angles permet lʼobtention dʼinformations précises et quantitatives sur les microstructures de précipitation à lʼéchelle nanométrique. Elle peut être utilisée avec des rayons X (DXPA ou SAXS) ou avec des neutrons (DNPA ou SANS). Cet article présente des méthodes simples pour extraire des informations sur les tailles et fractions volumiques des précipités à partir des spectres de diffusion. Différentes méthodes sont indiquées, ainsi que leur signification et différences. Des exemples dʼapplications sont donnés pour la caractérisation de microstructures complexes dans les cas suivants : mesures in-situ de cinétiques de précipitation dans Fe–Cu et Fe–Nb–C, précipitation non stoechiométrique évaluée par diffusion anormale des rayons X (ASAXS), et cartographie de précipitation dans les sections transverses de soudures.
Mot clés : Diffusion aux petits angles, DXPA, DNPA, Précipitation
Frédéric De Geuser 1; Alexis Deschamps 1
@article{CRPHYS_2012__13_3_246_0, author = {Fr\'ed\'eric De Geuser and Alexis Deschamps}, title = {Precipitate characterisation in metallic systems by small-angle {X-ray} or neutron scattering}, journal = {Comptes Rendus. Physique}, pages = {246--256}, publisher = {Elsevier}, volume = {13}, number = {3}, year = {2012}, doi = {10.1016/j.crhy.2011.12.008}, language = {en}, }
TY - JOUR AU - Frédéric De Geuser AU - Alexis Deschamps TI - Precipitate characterisation in metallic systems by small-angle X-ray or neutron scattering JO - Comptes Rendus. Physique PY - 2012 SP - 246 EP - 256 VL - 13 IS - 3 PB - Elsevier DO - 10.1016/j.crhy.2011.12.008 LA - en ID - CRPHYS_2012__13_3_246_0 ER -
Frédéric De Geuser; Alexis Deschamps. Precipitate characterisation in metallic systems by small-angle X-ray or neutron scattering. Comptes Rendus. Physique, Volume 13 (2012) no. 3, pp. 246-256. doi : 10.1016/j.crhy.2011.12.008. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2011.12.008/
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