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DOE OSTI · 3017246

Defect-Free Growth of Decagonal Quasicrystals around Obstacles

Wang, Kelly L. [Univ. of Michigan, Ann Arbor, MI (United States)]·Han, Insung [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000298318505)·Fijan, Domagoj [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000242562074)·Glotzer, Sharon C. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000271970085)·Shahani, Ashwin J. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:000000026157840X)
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Abstract

Quasicrystals are aperiodic solids with exotic physical properties. The mechanisms driving their growth are far from understood, particularly in the presence of rigid obstacles. Here, using in situ synchrotron x-ray tomography and molecular dynamics simulations, we investigate the interaction between decagonal quasicrystals and obstacles (shrinkage pores) during solidification of an Al 79 ⁢Co 6 ⁢Ni 15 alloy. The results reveal defect-free quasicrystal growth around the pores, independent of pore size and geometry. Our findings point to a universal feature of aperiodic solids: their ability to accommodate structural disruptions due to additional (phasonic) degrees of freedom. This Letter opens new possibilities for synthesizing large-scale, single quasicrystals from a liquid metal precursor.

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Wang, Kelly L. [Univ. of Michigan, Ann Arbor, MI (United States)], Han, Insung [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000298318505), Fijan, Domagoj [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000242562074), Glotzer, Sharon C. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000271970085), Shahani, Ashwin J. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:000000026157840X). 2025-10-17. Defect-Free Growth of Decagonal Quasicrystals around Obstacles. https://doi.org/10.1103/bsbs-rryl

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