The anelastic spectrum of the solid solution Sc-O has been investigated on a polycrystalline sample from 360 to 570K for oxygen concentrations varying between 0.024 and 0.91 at.% O, as estimated by electrical resistivity and intentional doping. Two relaxation processes appear at 430 and 520 K for the vibration frequency of 3.5 kHz; both peaks are stable with thermal cycling and their intensities increase with the oxygen content. The process at lower temperature has been tentatively interpreted as due to the stress-induced hopping of oxygen atoms between the non equivalent tetrahedral and octahedral interstitial sites. A possible mechanism for the higher temperature process could be the dissolu-tion/formation of interacting O-O pairs. (C) 2003 Elsevier B.V. All rights reserved.
Anelastic relaxation processes due to hopping of interstitial oxygen in scandium / Trequattrini, Francesco; F., Cordero; G., Cannelli; Cantelli, Rosario. - In: MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING. - ISSN 0921-5093. - STAMPA. - 370:1-2(2004), pp. 93-95. (Intervento presentato al convegno 13th International Conference on Internal Friction and Ultrasonic Attentuation in Solids tenutosi a Bilbao, SPAIN nel JUL 08-12, 2002) [10.1016/j.msea.2003.08.081].
Anelastic relaxation processes due to hopping of interstitial oxygen in scandium
TREQUATTRINI, Francesco;CANTELLI, Rosario
2004
Abstract
The anelastic spectrum of the solid solution Sc-O has been investigated on a polycrystalline sample from 360 to 570K for oxygen concentrations varying between 0.024 and 0.91 at.% O, as estimated by electrical resistivity and intentional doping. Two relaxation processes appear at 430 and 520 K for the vibration frequency of 3.5 kHz; both peaks are stable with thermal cycling and their intensities increase with the oxygen content. The process at lower temperature has been tentatively interpreted as due to the stress-induced hopping of oxygen atoms between the non equivalent tetrahedral and octahedral interstitial sites. A possible mechanism for the higher temperature process could be the dissolu-tion/formation of interacting O-O pairs. (C) 2003 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
