Free volume change in crystallization process of Zr-Cu-Al metallic glass studied by positron annihilation techniques

Fuminobu Hori, Takaaki Yano, Yoshihiko Yokoyama, Yasutake Akeno, Toyohiko J. Konno

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)

Abstract

Positron annihilation lifetime (PAL) and coincidence Doppler broadening (CDB) experiments have been performed to study free volume changes and atomic relaxation behavior in Zr-Cu-Al bulk metallic glass. Zr50Cu40Al10 metallic glass was annealed isothermally at 673 K, which is below the glass transition temperature (Tg). During this annealing, PAL was observed to decrease, indicating a decrease in free volume; whereas, no significant change in CDB spectra was detected. This observation implies that the relaxation below Tg takes place without a change in atomic configuration. As for specimens annealed at 723 K (>Tg) for 100 s and subsequently annealed isothermally at 673 K for 18,000 s, PAL decreased similarly, suggesting a decrease in free volume. In addition, CDB spectra showed a systematic fluctuation of electron momentum distribution, especially in a high momentum region. This indicates that a chemical reordering took place during crystallization process.

Original languageEnglish
Pages (from-to)207-210
Number of pages4
JournalJournal of Alloys and Compounds
Volume434-435
Issue numberSPEC. ISS.
DOIs
Publication statusPublished - 2007 May 31
Externally publishedYes

Keywords

  • Amorphous materials
  • Electronic states
  • Positron spectroscopies

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Free volume change in crystallization process of Zr-Cu-Al metallic glass studied by positron annihilation techniques'. Together they form a unique fingerprint.

Cite this