Elsevier

Acta Metallurgica

Volume 30, Issue 8, August 1982, Pages 1689-1696
Acta Metallurgica

An improved model for discontinuous precipitation

https://doi.org/10.1016/0001-6160(82)90190-0Get rights and content

Abstract

A description of physical factors governing discontinuous precipitation yielded a model some years ago which is now improved by removing some limitations, one after the other. In one version, the model now yields explicit expressions for the growth rate, the spacing, the remaining supersaturation and the composition at the three-phase junctions. Another version can be applied to non-ideal systems with high solute contents and high supersaturations.

Résumé

La description des facteurs physiques gouvernant la précipitation discontinue a conduit il y a pas mal d'années à un modèle que nous améliorons en nous affranchissant l'une après l'autre de certaines limitations. Une version du nouveau modèle donne les expressions explicites de la vitesse de croissance, de l'espacement, de la sursaturation résiduelle et de la composition au contact de trois phases. Une autre version s'applique aux systèmes non-idéaux avec des teneurs élevées en soluté et de fortes sursaturations.

Zusammenfassung

Vor vielen Jahren wurden die physikalischen Faktoren, die die diskontinuierliche Ausscheidung bestimmen, in einem Modell beschrieben. Dieses Modell wird in der vorliegenden Arbeit insoweit verbessert, als einige Einschränkungen schrittweise beseitigt werden. In einer Version liefert das Modell nun explizite Ausdrücke für die Wachstumsrate, den Abstand, die verbleibende Übersättigung und die Zusammensetzung an den Dreiphasenknoten. Eine weitere Version kann auf nicht-ideale Systeme mit hohen Konzentrationen und Übersättigungen angewendet werden.

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