Pressure and Temperature effects on the High Pressure Phase Transformation in Zirconium

Conference · Wed Jun 20 04:00:00 EDT 2012

OSTI ID:1044128

Escobedo-Diaz, Juan P ^[1]; Cerreta, Ellen K ^[1]; Brown, Donald W ^[1]; Trujillo, Carl P ^[1]; Rigg, Paulo A ^[1]; Bronkhorst, Curt A ^[1]; Addessio, Francis L ^[1]; Lookman, Turab ^[1]

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1. Los Alamos National Laboratory

At high pressure zirconium is known to undergo a phase transformation from the hexagonal close packed (HCP) alpha phase ({alpha}) to the simple hexagonal omega phase ({omega}). Under conditions of shock loading, the high-pressure omega phase is retained upon release. However, the hysteresis in this transformation is not well represented by equilibrium phase diagrams. For this reason, the influence of peak shock pressure and temperature on the retention of omega phase in Zr is explored in this study. In situ VISAR measurements along with post-mortem metallographic and neutron diffraction characterization of soft recovered specimens have been utilized to quantify the volume fraction of retained omega phase, morphology of the shocked alpha and omega phases, and qualitatively understand the kinetics of this transformation. This understanding of the role of peak shock stress will be utilized to address physics to be encoded in our present macro-scale models.

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: LDRD
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 1044128
• Report Number(s): LA-UR-12-22375
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
HCP LATTICES
HYSTERESIS
KINETICS
MORPHOLOGY
NEUTRON DIFFRACTION
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
PHYSICS
RETENTION
TEMPERATURE DEPENDENCE
TRANSFORMATIONS
ZIRCONIUM