Geophysical Research Letters · 2000 · 55 citations · 20 references
Natural SciencesMaterials EngineeringMaterials ScienceCeramicsPhase TransformationsSolid State PhysicsHigh-pressure ThermodynamicsPhase ChangePhase Transition AnalysisPhase TransitionsShock ResponseShock WavesHigh-pressure Phase RelationsHigh-pressure Phase TransformationsHigh-pressure Phase TransitionsPhase Transformation Of AluminaPressure-induced Phase TransitionsVolume ChangeVolume Change BehaviorVolume Change Mechanisms
A discontinuous volume change was observed on the Hugoniot curve of corundum (α‐Al 2 O 3 ) along the <a> axis by the inclined‐mirror streak photographic technique, probably due to a high‐pressure phase transformation. The transition pressure was measured to be 79 GPa, where shock temparature was estimated to be 860°C, in good agreement with a fully optimized quantum mechanical calculation. The volume change at the transition point was considered to be larger than 3%, which was larger than the theoretically predicted value of the corundum‐Rh 2 O 3 (II) transition, and was consistent with the recent static compression result by using diamond‐anvil cell. The occurence of the phase transformation in alumina under shock compression presents significant implication in earth interior science or ceramic science, and also seriously affects the interpretation of static and shock compresion experiments at ultra‐high pressures.
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Shock temperatures and melting of iron at Earth core conditions
Choong‐Shik Yoo, Niall Holmes, M. Ross et al. · Physical Review Letters · 1993 · 323 citations