ISSN: 1003-6326
CN: 43-1239/TG

Vol. 26    No. 11    November 2016

Effect of magnesium on dispersoid strengthening of Al-Mn-Mg-Si (3xxx) alloys
Zhen LI, Zhan ZHANG, X-Grant CHEN
(Department of Applied Sciences, University of Québec at Chicoutimi,
555 boul. de l’Université, Saguenay, Québec, G7H 2B1, Canada
Abstract: The effects of magnesium addition on the dispersoid precipitation as well as mechanical properties of 3xxx alloys were investigated. The microstructures in as-cast and heat-treated conditions were evaluated by optical microscopy and transmission electron microscopy. The results reveal that Mg has a strong influence on the distribution and volume fraction of dispersoids during precipitation heat treatment. The microhardness and yield strength at ambient temperature increase with increasing Mg content. The solid solution and dispersoid strengthening mechanisms of materials after heat treatment are quantitatively analyzed. Dispersoid strengthening for the alloys is the predominant strengthening mechanism after precipitation heat treatment. An analytical model is introduced to predict the evolution of ambient-temperature yield strength.
Key words: aluminum alloy; Mg; dispersoid strengthening; solid solution strengthening; microstructure characterization; mechanical properties
Superintended by The China Association for Science and Technology (CAST)
Sponsored by The Nonferrous Metals Society of China (NFSOC)
Managed by Central South University (CSU)