Affiliation:
1. Norwegian University of Science and Technology, Department of Physics, Trondheim, Norway
2. SINTEF, Materials and Chemistry, Trondheim, Norway
Abstract
Abstract
The effect of natural ageing time before artificial ageing has been investigated in four Al–Mg–Si(–Cu) alloys, with 0.4% Mg + 0.8% Si and 0.8% Mg + 0.4% Si, both with and without 0.14 at.% Cu. The precipitate microstructure was quantified by means of transmission electron microscopy. Varying the storage time before ageing for 170 min at 200°C, we observe an initial hardness increase after minutes, a decrease after several hours and another increase after weeks. The hardness decrease was most pronounced in the Mg-rich Cu-free alloy, caused by a reduced precipitate volume fraction. Adding Cu produces finer microstructures, higher hardness and reduces the negative effect of natural ageing regardless of the Mg/Si ratio of the alloy. With 1 week storage, an increase in the fraction of the Cu-containing precipitates L and Q′ was observed in the Cu-containing Si-rich and Mg-rich alloys respectively.
Subject
Materials Chemistry,Metals and Alloys,Physical and Theoretical Chemistry,Condensed Matter Physics
Cited by
31 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献