Mechanical spectroscopy of Al-Mg alloys

• Published in: Physics of metals and metallography Vol. 114; no. 4; pp. 327 - 338
• Main Authors: Golovin, I. S., Bychkov, A. S., Medvedeva, S. V., Hu, X. S., Zheng, M. Y.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-04-2013; Springer; Springer Nature B.V
• Subjects: Activation energy; Alloying; Alloys; Aluminum base alloys; Aluminum |c Binary systems; Annealing; Binary systems; Chemistry and Materials Science; Deformation; Diffusion; Instrument industry; Intermediate frequency; Magnesium |c Binary systems; Materials Science; Metallic Materials; Phase Transformations; Specialty metals industry; Spectroscopy; Structure; Toy industry; internal friction; relaxation and recrystallization; Al-Mg alloys
• ISSN: 0031-918X; 1555-6190
• DOI: 10.1134/S0031918X13020087

The internal friction of deformed, annealed, and quenched Al-Mg alloys with Mg contents of 0–12 wt % has been studied as a function of temperature. The measurements have been performed in the range of 25–580°C at 0.3–30 Hz using a DMA Q800 TA Instruments dynamic mechanical analyzer at the maximum amplitude of deformation ɛ
0
= 5 × 10
−5
. In annealed alloys with Mg contents up to 5 %, a relaxation IF peak with activation parameters (activation energy
H
≈ 1.7–2.1 eV) has been detected. In alloys with 8–12% Mg, this relaxation peak is absent and, at a lower temperature, another IF peak appears (with an activation energy
H
of about 1 eV), which is interpreted as the Zener peak in terms of the combination of activation parameters. The article discusses the nature of these peaks and the influence of alloying on the relaxation mechanisms. In cold-worked alloys, an IF pseudo-peak takes place, which is related to the recrystallization of samples, and its temperature position in the alloys that contain more than 5% Mg depends not only on the degree of deformation, but also on the dissolution temperature of the β phase.