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Title: High P-T phase transitions and P-V-T equation of state of hafnium

Abstract

We measured the volume of hafnium at several pressures up to 67 GPa and at temperatures between 300 to 780 K using a resistively heated diamond anvil cell with synchrotron x-ray diffraction at the Advanced Photon Source. The measured data allows us to determine the P-V-T equation of state of hafnium. The previously described [Xia et al., Phys. Rev. B 42, 6736-6738 (1990)] phase transition from hcp ({alpha}) to simple hexagonal ({omega}) phase at 38 GPa at room temperature was not observed even up to 51 GPa. The {omega} phase was only observed at elevated temperatures. Our measurements have also improved the experimental constraint on the high P-T phase boundary between the {omega} phase and high pressure bcc ({beta}) phase of hafnium. Isothermal room temperature bulk modulus and its pressure derivative for the {alpha}-phase of hafnium were measured to be B{sub 0} = 112.9{+-}0.5 GPa and B{sub 0}'=3.29{+-}0.05, respectively. P-V-T data for the {alpha}-phase of hafnium was used to obtain a fit to a thermodynamic P-V-T equation of state based on model by Brosh et al. [CALPHAD 31, 173-185 (2007)].

Authors:
; ; ;  [1]
  1. (FIU)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
DOE - BASIC ENERGY SCIENCESNSFUNIVERSITY
OSTI Identifier:
1046231
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Appl. Phys.; Journal Volume: 111; Journal Issue: (11) ; 06, 2012
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Hrubiak, Rostislav, Drozd, Vadym, Karbasi, Ali, and Saxena, Surendra K. High P-T phase transitions and P-V-T equation of state of hafnium. United States: N. p., 2016. Web. doi:10.1063/1.4726211.
Hrubiak, Rostislav, Drozd, Vadym, Karbasi, Ali, & Saxena, Surendra K. High P-T phase transitions and P-V-T equation of state of hafnium. United States. doi:10.1063/1.4726211.
Hrubiak, Rostislav, Drozd, Vadym, Karbasi, Ali, and Saxena, Surendra K. 2016. "High P-T phase transitions and P-V-T equation of state of hafnium". United States. doi:10.1063/1.4726211.
@article{osti_1046231,
title = {High P-T phase transitions and P-V-T equation of state of hafnium},
author = {Hrubiak, Rostislav and Drozd, Vadym and Karbasi, Ali and Saxena, Surendra K.},
abstractNote = {We measured the volume of hafnium at several pressures up to 67 GPa and at temperatures between 300 to 780 K using a resistively heated diamond anvil cell with synchrotron x-ray diffraction at the Advanced Photon Source. The measured data allows us to determine the P-V-T equation of state of hafnium. The previously described [Xia et al., Phys. Rev. B 42, 6736-6738 (1990)] phase transition from hcp ({alpha}) to simple hexagonal ({omega}) phase at 38 GPa at room temperature was not observed even up to 51 GPa. The {omega} phase was only observed at elevated temperatures. Our measurements have also improved the experimental constraint on the high P-T phase boundary between the {omega} phase and high pressure bcc ({beta}) phase of hafnium. Isothermal room temperature bulk modulus and its pressure derivative for the {alpha}-phase of hafnium were measured to be B{sub 0} = 112.9{+-}0.5 GPa and B{sub 0}'=3.29{+-}0.05, respectively. P-V-T data for the {alpha}-phase of hafnium was used to obtain a fit to a thermodynamic P-V-T equation of state based on model by Brosh et al. [CALPHAD 31, 173-185 (2007)].},
doi = {10.1063/1.4726211},
journal = {J. Appl. Phys.},
number = (11) ; 06, 2012,
volume = 111,
place = {United States},
year = 2016,
month = 7
}
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