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The authors recently reported that undercooled liquid Ag and Ag–Cu alloys both exhibit a first order phase transition from the homogeneous liquid (L-phase) to a heterogeneous solid-like G-phase under isothermal evolution. Here, we report a similar L–G transition and heterogenous G-phase in simulations of liquid Cu–Zr bulk glass. The thermodynamic description and kinetic features (viscosity) of the L-G-phase transition in Cu–Zr simulations suggest it corresponds to experimentally reported liquid–liquid phase transitions in Vitreloy 1 (Vit1) and other Cu–Zr-bearing bulk glass forming alloys. The Cu–Zr G-phase has icosahedrally ordered cores versus fcc/hcp core structures in Ag and Ag–Cu with a notably smaller heterogeneity length scale Λ . We propose the L–G transition is a phenomenon in metallic liquids associated with the emergence of elastic rigidity. The heterogeneous core–shell nano-composite structure likely results from accommodating strain mismatch of stiff core regions by more compliant intervening liquid-like medium.
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This content will become publicly available on July 1, 2026
Metallic messengers from the cosmos: Rare (Al,Cu)‐bearing meteorites from the Project Stardust collection
Abstract We report the discovery of (Al,Cu)‐bearing metallic alloys in two micrometeorites found in the Project Stardust collection gathered from urban rooftop environments in Norway. Most of the alloys are the same as those found in the Khatyrka meteorite and other micrometeorites, though one has a composition that has not been reported previously. Oxygen isotope ratio measurements using secondary ion mass spectrometry show that the Project Stardust samples reported here, like all earlier examples of natural (Al,Cu)‐bearing alloys, contain material of chondritic affinity.
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- Award ID(s):
- 2444631
- PAR ID:
- 10630156
- Publisher / Repository:
- The Meteoritical Society
- Date Published:
- Journal Name:
- Meteoritics & Planetary Science
- Volume:
- 60
- Issue:
- 7
- ISSN:
- 1086-9379
- Page Range / eLocation ID:
- 1609 to 1620
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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