Fracture of a minority phase at a stress concentration observed with synchrotron X-ray diffraction

This paper reports X-ray diffraction results obtained during in situ loading of a zirconium alloy specimen with large (∼100 μm) pre-grown hydrides at a 15 μm root radius flaw. Results indicate: (i) fracture of the hydrides can be resolved in situ, as confirmed by scanning electron microscopy; (ii) the residual stress field of the zirconium matrix governs the residual stress state of the hydride; and (iii) load is shed to the notch tip hydride phase on increasing applied load.