Athermal transformation behaviour and thermal hysteresis at the SiO2-α/ß-cristobalite phase transition
Schmahl, Wolfgang W.
European Journal of Mineralogy Volume 5 Number 2 (1993), p. 377 - 380
published: Apr 27, 1993
manuscript accepted: Dec 16, 1992
manuscript received: Nov 23, 1992
ArtNo. ESP147050502010, Price: 29.00 €
Abstract The α/ß-phase-transition of cristobalite (SiO2) shows a stable and reproducible hysteresis loop with phase coexistence on both slopes. The transition proceeds as a function of temperature rather than isothermally. The non-thermally-activated (athermal) behaviour is analogous to martensitic transformations in metals and alloys, and similar to the hysteresis of ferroics in an applied field. The observations suggest that self-pinning by coherency- strain is the cause of the 'thermal' hysteresis of non-quenchable structural phase transitions