On the inherent fracture mode of iridium at room temperature

Experimental data that allow the determination of an inherent fracture mode of the refractory fcc metal iridium at room temperature are considered in this paper. High purity iridium and Ir-3 wt%Re-2 wt%Ru are chosen as the model substances. Brittle transgranular fracture is the sole fracture mode exhibited by the samples at room temperature. Neither recrystallization in 10−5 Torr vacuum nor the geometry of applied stress or grain size induce the brittle intercrystalline fracture in these materials.