|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Ultrafine-grained and Heterostructured Materials (UFGH XII)
||Breaking the strength-toughness barrier through impact-induced recrystallization of single-crystal silver microcubes
||Claire Griesbach, Jizhe Cai, Ramathasan Thevamaran
|On-Site Speaker (Planned)
As typically mutually exclusive properties, optimizing both strength and toughness requires exploitation of complementary deformation mechanisms provided by different structural heterogeneities. We show that nanostructural changes induced through impact of single-crystal silver microcubes lead to a two-fold improvement in both strength and toughness. Single-crystal silver microcubes are impacted onto a rigid target at ~400 m/s using a laser-induced projectile impact testing (LIPIT) apparatus and undergo extensive recrystallization, forming a gradient-nano-grained (GNG) structure. Stress-strain curves obtained through in situ SEM microcompression testing of pillars FIB-milled from the impacted cubes show ultra-high hardening rates, high yield strengths, and large compressive toughness. The impacted cubes outperform both single-crystal microcubes and bulk polycrystalline silver, boasting superior strength and toughness. The improvement in both properties is attributed to a combination of inter- and intragranular plasticity mechanisms elicited through the spatial gradient of nanograins to coarse grains representative of a GNG structure.
||Mechanical Properties, Characterization, Other