Microstructure and strength of quasicrystal containing extruded Mg-Zn-Y alloys for elevated temperature application

Alok Singh, M. Watanabe, A. Kato, A. P. Tsai

Research output: Contribution to journalArticlepeer-review

164 Citations (Scopus)

Abstract

Microstructural studies have been made on alloys Mg95 Zn4.2Y0.8 and Mg92.5Zn6.5Y containing icosahedral quasicrystalline phase extruded at two different temperatures of 523 K and 673 K and correlated to room temperature and higher temperature tensile strength. Icosahedral phase occurred as particles about half micron size at grain boundaries and as nano-sized precipitates in the matrix. Solutionizing at 673 K (1 h) was employed followed by annealing at 473 K for finer precipitation in the matrix. Solutionizing produced a fine precipitation of a ternary phase τ1 in the matrix of the Mg95Zn4.2 Y0.8 alloy, replaced by icosahedral precipitates on annealing. The Mg92.5Zn6.5Y alloy containing larger volume fraction of icosahedral phase showed higher strength. Solutionizing produced a composite of icosahedral and a H-Mg25 Zn58Y17 hexagonal phase composite. Yield stresses of over 250 MPa at room temperature (elongation 15-20%) and 150 MPa at 473 K (UTS 240 MPa, elongation 40%) were obtained upon post extrusion annealing.

Original languageEnglish
Pages (from-to)382-396
Number of pages15
JournalMaterials Science and Engineering A
Volume385
Issue number1-2
DOIs
Publication statusPublished - 2004 Nov 15

Keywords

  • Extrusion
  • Magnesium alloys
  • Microstructure
  • Quasicrystal
  • Tensile strength

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Microstructure and strength of quasicrystal containing extruded Mg-Zn-Y alloys for elevated temperature application'. Together they form a unique fingerprint.

Cite this