Paper Title:
Development of a New 7xxx Ageing Model
  Abstract

A kinetic model has been developed to simulate the precipitate size distribution and the resulting yield strength during ageing of 7xxx alloys. The η phase is the only one considered. The kinetic model is mean field: precipitates of different sizes see each other through the average solid solution. Precipitates are assumed to be homogeneous in concentration and are allowed to change chemistry. Local equilibrium is assumed at the matrix-precipitate interface; the equilibrium concentrations are corrected by the curvature effect. Values of the equilibrium concentrations at the matrix-precipitate interface are solved by an iterative method: the resulting flux for each element must be compatible with equilibrium conditions and with the changing stoechiometry of the considered precipitate while maximizing the energy gained. The yield strength is derived from the precipitate size distribution through a mixture law combining the effect of each individual precipitate. The model can take into account non-isothermal treatments and can therefore simulate complicated multi-stage ageing treatment as well as a FSW weld. Results of the model are discussed and compared measurements.

  Info
Periodical
Materials Science Forum (Volumes 519-521)
Edited by
W.J. Poole, M.A. Wells and D.J. Lloyd
Pages
321-326
DOI
10.4028/www.scientific.net/MSF.519-521.321
Citation
C. Sigli, "Development of a New 7xxx Ageing Model", Materials Science Forum, Vols. 519-521, pp. 321-326, 2006
Online since
July 2006
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: T. Marlaud, B. Baroux, Alexis Deschamps, J.L. Chemin, C. Hénon
Abstract:The microstructural evolution has been investigated in three alloys of the 7000 series possessing increasing zinc contents by combining...
455
Authors: Alexis Deschamps, Myriam Dumont, Ludovic Lae, Françoise Bley
Abstract:This paper presents two studies illustrating the possibilities of Small-Angle X-ray Scattering for characterising quantitatively the state...
1349
Authors: Alexis Deschamps, Fabien Perrard, Françoise Bley, Patricia Donnadieu, Philippe Maugis
Abstract:This paper presents a physically based precipitation model which aims at describing precipitation kinetics when it occurs exclusively on...
4161
Authors: Ivan Holzer, Ernst Kozeschnik
Abstract:During ageing of Fe-Cu alloys, for standard ageing conditions, peak hardness and strength is often observed after several hours. The...
2579
Authors: Yong Qiang Long, Ping Liu, Yong Liu
Abstract:The phase-field model is established for precipitation transformations in multi-component alloy, which incorporates the interfacial energy...
184