Bulk glassy and quasicrystalline (Zr65Al7.5Cu 27.5)100-xTix Alloys and Their Mechanical Properties

Abstract

The glass-forming ability (GFA) and thermal stability of (Zr 65Al7.5Cu27.5)100-xTix (x = 0-15; in at%) alloys have been investigated. It was revealed that a certain amount of Ti addition could improve the GFA of Zr65Al 7.5Cu27.5 alloy effectively. The best bulk metallic glass (BMG) forming composition was found at (Zr65Al7.5Cu 27.5)93Ti7. Bulk glassy samples with diameter of 7 mm were made by means of copper mold casting. Further Ti additions deteriorated GFA and led to the precipitation of icosahedral phase, and 3 mm quasicrystalline cylinder was obtained at (Zr65Al 7.5Cu27.5)90Ti10. Room temperature compression testing showed that the ouasicrvstalline alloy had a fracture strength of 1875MPa, being 300MPa larger than that of the Zr65Al 7.5Cu27.5)93Ti727.5)93117 monolithic BMG. © 2007 The Japan Institute of Metals.