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Title: A flexible and springy form of ice
Water ice is ordinarily fragile and breaks if extended by just <0.1 % ( 1 ). On page 187 of this issue Xu et al. ( 2 ) show that fibers of cold ice a few micrometers or less in diameter can bend without breaking into a near-circular shape tens of micrometers in radius. Upon unloading, the fibers spring back to their original shape. Such strains are near the theoretical limit of ∼15% ( 3 ), so the deformation is completely elastic. The microfibers can transmit visible light as effectively as state-of-the-art on-chip light guides ( 4 , 5 ). The authors also find that extreme bending creates a near-surface layer on the compressive side that transforms relatively quickly from ice I h (hexagonal crystal structure) to ice II (rhombohedral crystal structure). This pronounced elasticity and transparency reflect the absence of defects within the material, and the structure change implies a low barrier for the ice I h -to-II transformation.  more » « less
Award ID(s):
1947107
PAR ID:
10334534
Author(s) / Creator(s):
Date Published:
Journal Name:
Science
Volume:
373
Issue:
6551
ISSN:
0036-8075
Page Range / eLocation ID:
158 to 158
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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