Ion-irradiation-induced amorphization of Zr(Cr, Fe)2 precipitate

The 600 keV Ne+ ion irradiation and in-situ TEM observation were performed in a Zircaloy 4 using the HVEM-Tandem Facility at 350°C, and the ion flux was 2.5×1012 cm-2&middots-1. The structural damage upon irradiation was monitored by the selected area electron diffraction patterns (SAED) under in-situ TEM observations. The amorphization transformation was determined by the disappearance of all diffraction maxima in the SAED patterns and microstructural contrast. The results show that in situ 600 keV Ne+ irradiation at 350°C, stacking fault contrast starts fading up to 0.2 dpa, and disappears basically up to 0.4 dpa, and the disorder of Zr(Cr, Fe)2 precipitate happens at the same time. The Zr(Cr, Fe)2 precipitate becomes amorphous at a dose of about 2.7 dpa.