The thermodynamics of and strengthening due to co-clusters: general theory and application to the case of Al-Cu-Mg alloys


Starink, M.J. and Wang, S.C. (2009) The thermodynamics of and strengthening due to co-clusters: general theory and application to the case of Al-Cu-Mg alloys. Acta Materialia, 57, 2376-2389. (doi:10.1016/j.actamat.2009.01.021).

Download

[img] PDF
Download (1531Kb)

Description/Abstract

Co-clusters in ternary or higher order metallic alloys are metastable structures involving two or more distinct alloying atoms that retain the structure of the host lattice. A thermodynamic model based on a single interaction energy of dissimilar nearest neighbour alloying elements is presented, and a model for the strengthening due to these co-cluster dimers is derived. The model includes a new treatment of (short-) order strengthening relevant to these co-clusters and further encompasses modulus hardening and chemical hardening. The models are tested against data on a wide range of Al-Cu-Mg alloys treated at temperatures between 20 and 220ºC. Both quantitative calorimetry data on the enthalpy change due to co-cluster formation and strengthening due to co-clusters is predicted well. It is shown that in general (short-range) order strengthening will be the main strengthening mechanism.

Item Type: Article
ISSNs: 1359-6454 (print)
Related URLs:
Keywords: co-clusters, cosegregation, calorimetry, enthalpy, entropy, free energy, strengthening, modulus hardening, chemical hardening, guinier-preston, GPB, 2024, Al-Cu-Mg, Al-Mg-Si, co-segregation
Subjects: T Technology > TN Mining engineering. Metallurgy
Divisions: University Structure - Pre August 2011 > School of Engineering Sciences > Engineering Materials & Surface Engineering
ePrint ID: 63828
Date Deposited: 07 Nov 2008
Last Modified: 27 Mar 2014 18:45
URI: http://eprints.soton.ac.uk/id/eprint/63828

Actions (login required)

View Item View Item