AN ANALYSIS OF THE PHASE-DECOMPOSITION IN NB-ZR ALLOY BASED ON THE SYSTEM FREE-ENERGY THEORY

Authors
TODA Y NAKAGAWA H KOYAMA T MIYAZAKI T
Citation
Y. Toda et al., AN ANALYSIS OF THE PHASE-DECOMPOSITION IN NB-ZR ALLOY BASED ON THE SYSTEM FREE-ENERGY THEORY, Materials science & engineering. A, Structural materials: properties, microstructure and processing, 255(1-2), 1998, pp. 90-97
Citations number
32
Categorie Soggetti
Material Science
Journal title
Materials science & engineering. A, Structural materials: properties, microstructure and processing → ACNP
ISSN journal
09215093
Volume
255
Issue
1-2
Year of publication
1998
Pages
90 - 97
Database
ISI
SICI code
0921-5093(1998)255:1-2<90:AAOTPI>2.0.ZU;2-2
Abstract
The behaviour of the phase decomposition in Nb-Zr binary alloy with is othermal ageing was investigated experimentally and theoretically. Fir st, the microstructural changes in Nb-30, 40, 50 and 60 at.% Zr alloys aged at 723-973 K were observed by means of a transmission electron m icroscope (TEM), and the time-temperature-transformation (TTT) diagram s of each composition were obtained experimentally. As a result, it is found that the sequences of the phase transformation in this alloy ar e divided into four types. Furthermore, by estimating the total free e nergy of the microstructure and deciding the energetic minimum path, t he phase transformation process was predicted theoretically. The diagr ams obtained by calculation agreed well with experimental ones, and wh ich suggest that an energetic analysis is useful to predict the sequen ces of phase transformation of alloys with ageing. (C) 1998 Elsevier S cience S.A. All rights reserved.