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Title: Tensile ductility and necking in consolidated amorphous alumina

Oxide glass, one of the most transformative materials in the modern world, breaks easily under load due to its brittleness. Using classical molecular dynamics simulations, we prepared amorphous alumina by consolidating glass nanoparticles at room temperature. We showed that consolidated amorphous alumina exhibits work hardening ability, hence deforms homogeneously and fractures via necking under tension, while amorphous alumina obtained from the traditional melt‐quench process fractures catastrophically due to severe shear banding. This finding suggests that if processed properly, amorphous oxides could deform and fracture like ductile metals, which will significantly expand the applications of oxide glasses into new areas where load bearing or mechanical reliability is necessary.

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Award ID(s):
1936368 1508410
Publication Date:
Journal Name:
Journal of the American Ceramic Society
Page Range or eLocation-ID:
p. 958-965
Sponsoring Org:
National Science Foundation
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