On anomalous strain hardening in iridium crystals

This note clarifies an aspect of the mechanical response of iridium, namely strain hardening, which has been reported as anomalous and was recently highlighted in the context of atomistic simulations of screw dislocation cores in this material. Here we show that the plastic deformation of iridium crystals exhibits no anomaly at all; the measured rate of strain hardening is fully consistent with normalized values for other face-centered cubic metals and cannot be used to explain the unusual fracture response of iridium.