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Title: External Field Assisted Freeze Casting
Freeze casting under external fields (magnetic, electric, or acoustic) produces porous materials having local, regional, and global microstructural order in specific directions. In freeze casting, porosity is typically formed by the directional solidification of a liquid colloidal suspension. Adding external fields to the process allows for structured nucleation of ice and manipulation of particles during solidification. External control over the distribution of particles is governed by a competition of forces between constitutional supercooling and electromagnetism or acoustic radiation. Here, we review studies that apply external fields to create porous ceramics with different microstructural patterns, gradients, and anisotropic alignments. The resulting materials possess distinct gradient, core–shell, ring, helical, or long-range alignment and enhanced anisotropic mechanical properties.  more » « less
Award ID(s):
1660979
NSF-PAR ID:
10089614
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Ceramics
Volume:
2
Issue:
1
ISSN:
2571-6131
Page Range / eLocation ID:
208 to 234
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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