Continuous phase separation in a Nickel-Aluminium alloy

doi:10.1016/0001-6160(82)90142-0

Acta Metallurgica

Volume 30, Issue 12, December 1982, Pages 2219-2225

https://doi.org/10.1016/0001-6160(82)90142-0 Get rights and content

Abstract

Atom probe field-ion microscopy has been used as the principal investigative technique in a study of the decomposition of a nickel 14.1 at.% aluminium alloy at 898 K. Long composition versus distance data sequences have been taken for specimens probed in 〈110〉 and 〈111〉 directions. Fast Fourier spectral analysis has been applied to these data chains and the variations in these spectra compared with the predictions of continuous transformation theory. This study has established the importance of supersaturation in controlling the possibility of a spinodal reaction and those specimens of Ni-14.1 at.% Al quenched sufficiently rapidly prior to ageing have been shown to transform spinodally.

Résumé

Nous avons utilisé principalement la sonde atomique à émission d'ions pour étudier la décomposition d'un alliage Ni-14,1 at.% Al à 898 K. Nous avons pris de longues séquences de composition en fonction de la distance pour des échantillons étudiés dans les directions 〈110〉 et 〈111〉. Nous avons appliqué à ces chaines de données une analyse spectrale de Fourier rapide et nous avons comparé les variations de ces spectres avec les prévisions de la théorie de la transformation continue. Cette étude a mis en évidence l'importance de la sursaturation dans le contrôle de la possibilité d'une réaction spindole; les échantillons de Ni-14.1 at.% Al trempés suffisamment rapidement avant le vieillissement subissaient une transformation spinodale.

Zusammenfassung

Die Entmischung der Legierung Nickel-(14,1 At.%) Aluminium wurde im wesentlichen mit der Feldionenmikroskopie als Atomsonde untersucht. Ergebnisse über die Zusammensetzung als Funktion des Abstandes wurden an Proben in den Richtungen 〈110〉 und 〈111〉 erhalten. Die Datenketten werden mit schneller Fourierspektralanalyse ausgewertet; die Änderungen in diesen Spektren werden mit den Voraussagen der Theorie der kontinuierlichen Transformation verglichen. Diese Untersuchung zeigt, daβ die Übersättigung für den Ablauf einer spinodalen Reaktion wichtig ist. Diejenigen Proben, die vor der Ausagerung genügend rasch abgeschreckt worden sind, wandeln sich spinodal um.

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Continuous phase separation in a Nickel-Aluminium alloy

Abstract

Résumé

Zusammenfassung

Acta metall.

Acta metall.

Acta metall.

Acta metall.

Acta metall.

Acta metall.

Acta metall.

Solid St. Phys.

J. Phys. E., Sci. Instrum.

Acta metall.

Acta metall.