Fracture Parameters and Plasticity of the Zr–Nb–Sn–Fe Tubes with Different Hydrides Orientations during the Mechanical Testing

The results of mechanical testing and fractography of the ring samples, made of the model Zr–Nb–Sn–Fe alloy, are presented. The most reliable macro- and micro- parameters to quantify the fracture surface are defined. The correlations of some hydride microstructure metrics with fracture parameters are investigated. The advantages and disadvantages of individual metrics are revealed. Threshold stress for the near-surface radial hydride fracture at room temperature is obtained.