ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
In Al-Cu-Mg with compositions in the α+S phase field, precipitation hardening is a twostageprocess. Experimental evidence shows that the main precipitation sequence in alloys with Cucontents in excess of 1wt% is involves Cu-Mg co-clusters, GPBII/S'' and S. The first stage of theage hardening is due to the formation of Cu-Mg co-clusters, and the hardening can be modelledwell by a modulus hardening mechanism. The appearance of the orthorhombic GPBII/S'' does notinfluence the hardness. The second stage of the hardening is due to the precipitation of S phase,which strengthens the alloy predominantly through the Orowan looping mechanism. These findingsare incorporated into a multi-phase, multi mechanism model for yield strength of Al-Cu-Mg basedalloys. The model is applied to a range of alloys with Cu:Mg ratios between 0.1 and 1 and to heattreatments ranging from room temperature ageing and artificial isothermal ageing to rapid heatingto the solution treatment temperature. The predictive capabilities of this model are reviewed and itsconstitutive components are compared and contrasted with a range of other methods, such as theKampmann-Wagner and JMAK models for precipitation as well as the LSW model for coarsening
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.519-521.251.pdf
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