Phase transformation induced plasticity in high-strength hexagonal close packed Co with stacking faults

Deformation twinning and dislocation glide are two primary deformation mechanisms in hexagonal close packed (HCP) metals. Here we show, via in situ micropillar compression tests, that HCP Co pillars with high-density stacking faults exhibit a high yield strength and significant plasticity. Transmission electron microscopy studies reveal the formation of extensive face-centered cubic (FCC) Co phase after deformation. Molecular dynamics...