J. Li; Q. Tang; N. Chawla; M. Hassani
Scripta Materialia 273 (2026) 117089
While the deformation mechanisms of Al-SiC nanolaminates under quasi-static and low stain rate conditions have
been extensively studied, their behavior under ultra-high strain rates are not well-understood. Here we report on
the high strain-rate behavior of Al-SiC metal-ceramic nanolaminates with layer thicknesses ranging from 10 to
100 nm by nanoindentation tests and laser induced microparticle impact tests. The effective strain rates spanned
nine orders of magnitude, ranging from 10^–1 to 10^8 s-1. While the hardness of Al-SiC nanolaminates strongly
depends on layer thickness at low strain rates, the differences progressively decreased with increasing strain rate,
ultimately converging under ultra-high strain rate impact. At low strain rates, deformation progresses slowly,
layer by layer; whereas with increasing strain rate, it transitions toward continuum, bulk-like behavior, where a
large number of layers deform collectively and the mechanical response becomes increasingly governed by the
volume fraction rather than the layer thickness of the constituents.