Internal friction in Fe–Al–Si alloys at elevated temperatures

Interactions between solute atoms in Fe–Si–Al–C alloys as studied by mechanical spectroscopy

“…The Zener relaxation had been studied previously mainly in binary Fe-Al and Fe-Si alloys [25,26], but first results on ternary Fe-Si-Al were also considered briefly [23,24]. Being located at ∼900 K for frequencies of 200-500 Hz (e.g., in Fe-Al [22]), close to the upper temperature limit of our vibrating-reed equipment, the Zener peak is more readily studied using low-frequency techniques.…”

“…The suppression is not always complete, however, but shows some unsystematic variation the reason of which is at present not clear. As discussed in more detail elsewhere [24], even in the "ordered" concentration range quenching may produce some partial disorder, resulting in a residual Zener peak which seems to consist of two components. Tentative assignment of these components to separate Al-Al and Si-Si pairs [24] is not free from doubt, however.…”

“…Damping Q −1 and resonance frequency f of torsional or flexural vibrations were measured in two different frequency ranges, during heating with 1 K/min between room temperature and 873 K, using an inverted torsion pendulum (0.5-3 Hz) at Tula State University and different vibrating-reed set-ups (150-3000 Hz) at Braunschweig University. We will focus here only on internal friction in the known temperature-frequency ranges of the Snoek-type and Zener relaxations; microstructural characterization, elastic modulus data, and full damping spectra including other effects, as well as more experimental details, can be found elsewhere [18,[21][22][23][24]. …”

“…After some preliminary work in different context [21,22,24], the Snoek-type and Zener relaxations in Fe-Si-Al-C alloys are studied in the present paper with respect to the information they can provide on the s-i (Si-C, Al-C) as well as s-s (Al-Al, Si-Si, Al-Si) interactions, in particular at compositions showing a double (Fe-C-Fe + Fe-C-Me) Snoek-type peak. As these compositions are clearly in the "concentrated" range where a quantitative theoretical treatment is difficult, various parameter variations are necessary to figure out the main characteristics of the relaxation processes.…”

The internal friction peaks correlated to the relaxation of atomic defects in Fe47Al53 alloy

“…In the alloys with relatively high Al contents such as more than 25 at%, ordering significantly suppresses the Zener relaxation [2,5], and the Zener peak is impossible appearing in completely ordered structures [6]. Golovin et al [7,8] have recently given the different activation energies for the Zener relaxation in A2, D0 3 and B2 phases of Fee22Al and Fee26Al alloys through isothermal mechanical spectroscopy technique, and the influence of Si additions on the Zener relaxation and ordering of Fee20Al and Fee5Al alloys, which will be helpful for characterizing the atomic defects in FeeAl alloys.…”