Shock synthesis of quasicrystals with implications for their origin in asteroid collisions
Here, we designed a plate impact shock recovery experiment to simulate the starting materials and shock conditions associated with the only known natural quasicrystals, in the Khatyrka meteorite. At the boundaries among CuAl5, (Mg0.75Fe0.252+)2SiO4 olivine, and the stainless steel chamber walls, the recovered specimen contains numerous micron-scale grains of a quasicrystalline phase displaying face-centered icosahedral symmetry and low phason strain. The compositional range of the icosahedral phase is Al68-73Fe11-16Cu10-12Cr1-4Ni1-2 and extends toward higher Al/(Cu+Fe) and Fe/Cu ratios than those reported for natural icosahedrite or for any previously known synthetic quasicrystal in the Al-Cu-Fe system. The shock-induced synthesis demonstrated in this experiment reinforces the evidence that natural quasicrystals formed during a shock event but leaves open the question of whether this synthesis pathway is attributable to the expanded thermodynamic stability range of the quasicrystalline phase at high pressure, to a favorable kinetic pathway that exists under shock conditions, or to both thermodynamic and kinetic factors.
- Research Organization:
- Univ. of Nevada, Las Vegas, NV (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA)
- Contributing Organization:
- US National Science Foundation (NSF) EAR-1426526 University of Firenze, Italy NSF-MRSEC Program through New York University DMR-0820341 NSF-MRSEC Program through Princeton Center for Complex Materials DMR-0819860 NSF EAR-0318518 DMR-0080065
- Grant/Contract Number:
- NA0001982
- OSTI ID:
- 1332397
- Journal Information:
- Proceedings of the National Academy of Sciences of the United States of America, Vol. 113, Issue 26; ISSN 0027-8424
- Publisher:
- National Academy of Sciences, Washington, DC (United States)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
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