Phase transformations during high-pressure torsion (HPT) in titanium, cobalt and graphite

Kaveh Edalati, Zenji Horita

Research output: Contribution to journalConference article

1 Citation (Scopus)

Abstract

Several elements were processed by high-pressure torsion and phase transformations were investigated. Titanium exhibited a transition from hcp to an ω phase at pressures higher than 4 GPa, while the transition was facilitated with increasing the shear strain. The stability of ω phase appeared to decrease with decreasing the grain size to the nanometer level (e.g., by processing at cryogenic temperatures and/or by consolidation of powders). Cobalt exhibited a transition from metastable fcc to hcp until the grain size reached the submicrometer level, but the fcc phase appeared to be more stable with decreasing the grain size to the nanometer level. Graphite exhibited a transition to diamond-like carbon (DLC), while the formation of DLC was facilitated with increasing the pressure, temperature and strain.

Original languageEnglish
Article number012099
JournalIOP Conference Series: Materials Science and Engineering
Volume63
Issue number1
DOIs
Publication statusPublished - Jan 1 2014
Event6th International Conference on Nanomaterials by Severe Plastic Deformation, NanoSPD 2014 - Metz, France
Duration: Jun 30 2014Jul 4 2014

Fingerprint

Graphite
Cobalt
Titanium
Torsional stress
Diamond
Phase transitions
Diamonds
Carbon
Shear strain
Consolidation
Powders
Cryogenics
Temperature
Processing

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Engineering(all)

Cite this

Phase transformations during high-pressure torsion (HPT) in titanium, cobalt and graphite. / Edalati, Kaveh; Horita, Zenji.

In: IOP Conference Series: Materials Science and Engineering, Vol. 63, No. 1, 012099, 01.01.2014.

Research output: Contribution to journalConference article

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