Details

Autor(en) / Beteiligte

• Park, E.S.
• Kim, D.H.

Titel

Phase separation and enhancement of plasticity in Cu–Zr–Al–Y bulk metallic glasses

Ist Teil von

• Acta materialia, 2006-06, Vol.54 (10), p.2597-2604

Ort / Verlag

Oxford: Elsevier Ltd

Erscheinungsjahr

2006

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Enhancement of plasticity and the occurrence of liquid-state phase separation have been investigated by partially substituting Zr with Y in Cu 46Zr 47− x Y x Al 7 ( x = 0, 2, 5, 10, 15, 20, 25, 30, 35) alloys. Since Y has a positive enthalpy of mixing with Zr (+35 kJ/mol) in the liquid state, the alloy composition moves to the metastable miscibility gap of the two amorphous phases with increasing Y content. Phase separation into Y-rich and Zr-rich amorphous phases occurs during cooling from the liquid state when the Y content is above 15 at.%. The bulk amorphous alloys consisting of two phase-separated amorphous phases exhibit extreme brittleness, while the single-phase amorphous alloys containing 2–5 at.% of Y exhibit enhanced plasticity because of the introduction of chemical inhomogeneity in the amorphous matrix. The results indicate that the addition of an element having a positive enthalpy of mixing with the constitutive element in bulk amorphous alloys can increase the plasticity as well as the glass-forming ability, but for a limited composition range.