Structure-property relationships from universal signatures of plasticity in disordered solids
Abstract
When deformed beyond their elastic limits, crystalline solids flow plastically via
particle rearrangements localized around structural defects. Disordered solids also
flow, but without obvious structural defects. We link structure to plasticity in
disordered solids via a microscopic structural quantity, “softness,” designed by
machine learning to be maximally predictive of rearrangements. Experimental results
and computations enabled us to measure the spatial correlations and strain response
of softness, as well as two measures of plasticity: the size of rearrangements and
the yield strain. All four quantities maintained remarkable commonality in their values
for disordered packings of objects ranging from atoms to grains, spanning 7 to 13
orders of magnitude in diameter and elastic modulus. These commonalities suggest
that the spatial correlations and strain response of softness correspond to
rearrangement size and yield strain, respectively.