skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Crystal structures of group IVa metals at ultrahigh pressures

Abstract

High-pressure energy-dispersive x-ray-diffraction studies were carried out on the group IVa metals hafnium (Hf) to 252 GPa (to a volume compression {ital V}/{ital V}{sub 0} of 0.48) and titanium (Ti) to 87 GPa using a synchrotron source. Two new structural phase transformations between an hcp phase and an {omega} phase and between the {omega} phase and a bcc phase (isostructural with group V transition metals) were observed during both compression and decompression in Hf. Equilibrium transformation pressures for Hf are 38{plus minus}8 and 71{plus minus}1 GPa for the hcp-to-{omega} and {omega}-to-bcc phase transformations, respectively, at room temperature. In Ti, only the hcp-to-{omega} phase transition was observed above 8 GPa, and the {omega} phase was stable to 87 GPa. The crystal structure sequences of Ti, Zr, and Hf at ultrahigh pressures are discussed.

Authors:
; ; ; ;  [1]
  1. Department of Materials Science and Engineering, Cornell University, Ithaca, NY (USA)
Publication Date:
OSTI Identifier:
6174997
Resource Type:
Journal Article
Journal Name:
Physical Review, B: Condensed Matter; (USA)
Additional Journal Information:
Journal Volume: 42:10; Journal ID: ISSN 0163-1829
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; HAFNIUM; CRYSTAL STRUCTURE; TITANIUM; ZIRCONIUM; BCC LATTICES; CRYSTAL-PHASE TRANSFORMATIONS; EQUATIONS OF STATE; HCP LATTICES; PRESSURE DEPENDENCE; VERY HIGH PRESSURE; CRYSTAL LATTICES; CUBIC LATTICES; ELEMENTS; EQUATIONS; HEXAGONAL LATTICES; METALS; PHASE TRANSFORMATIONS; TRANSITION ELEMENTS; 360102* - Metals & Alloys- Structure & Phase Studies

Citation Formats

Xia, H, Parthasarathy, G, Luo, H, Vohra, Y K, and Ruoff, A L. Crystal structures of group IVa metals at ultrahigh pressures. United States: N. p., 1990. Web. doi:10.1103/PhysRevB.42.6736.
Xia, H, Parthasarathy, G, Luo, H, Vohra, Y K, & Ruoff, A L. Crystal structures of group IVa metals at ultrahigh pressures. United States. https://doi.org/10.1103/PhysRevB.42.6736
Xia, H, Parthasarathy, G, Luo, H, Vohra, Y K, and Ruoff, A L. 1990. "Crystal structures of group IVa metals at ultrahigh pressures". United States. https://doi.org/10.1103/PhysRevB.42.6736.
@article{osti_6174997,
title = {Crystal structures of group IVa metals at ultrahigh pressures},
author = {Xia, H and Parthasarathy, G and Luo, H and Vohra, Y K and Ruoff, A L},
abstractNote = {High-pressure energy-dispersive x-ray-diffraction studies were carried out on the group IVa metals hafnium (Hf) to 252 GPa (to a volume compression {ital V}/{ital V}{sub 0} of 0.48) and titanium (Ti) to 87 GPa using a synchrotron source. Two new structural phase transformations between an hcp phase and an {omega} phase and between the {omega} phase and a bcc phase (isostructural with group V transition metals) were observed during both compression and decompression in Hf. Equilibrium transformation pressures for Hf are 38{plus minus}8 and 71{plus minus}1 GPa for the hcp-to-{omega} and {omega}-to-bcc phase transformations, respectively, at room temperature. In Ti, only the hcp-to-{omega} phase transition was observed above 8 GPa, and the {omega} phase was stable to 87 GPa. The crystal structure sequences of Ti, Zr, and Hf at ultrahigh pressures are discussed.},
doi = {10.1103/PhysRevB.42.6736},
url = {https://www.osti.gov/biblio/6174997}, journal = {Physical Review, B: Condensed Matter; (USA)},
issn = {0163-1829},
number = ,
volume = 42:10,
place = {United States},
year = {Mon Oct 01 00:00:00 EDT 1990},
month = {Mon Oct 01 00:00:00 EDT 1990}
}