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Proton irradiation at temperatures of 310 and 350° C has been explored as a method of studying radiation effects in Zircaloy 4 under power-reactor conditions. The dislocation-loop and hardness evolution are similar to those observed under neutron irradiation. Amorphization and Fe loss at Zr(Cr,Fe)2 precipitates are observed. Energy-filtered images indicate Fe accumulation in the matrix near the precipitate, a phenomenon not reported in neutron-irradiated alloys. [ABSTRACT FROM AUTHOR]

This article summarizes recent studies of electron irradiation damage in sodium borosilicate, iron phosphate and aluminophosphate glass waste forms using a modern analytical electron microscope. Three different borosilicate (wt%)(17.72%, B2O3-16.67%, Na2O-64.61% SiO2, 17.78% B2O3-15.83% Na2O61.39% SiO2-4.99% Fe2O,3 and 17.86% B2O3-15.90'% Na2O-61.63% SiO2-4.61% FeO) and iron phosphate (mol%) (45% Fe2O3-55% P2O5 20% Fe2O3 80%, P2O5, and 20%, Fe2O3 20% Na2O5) glasses, and an aluminophosphate (mol%) (44.5%, P2O5-31.5%-Al2O3-20.2% Na2O-3.8% K2O) glass were studied. Results indicate that all these glasses decomposed under the 200kV electron irradiation (at doses higher than 1.0 × 1026 cm²). Migration of alkali elements from the irradiated centres lo the peripheries under irradiation occurred in the alkali element-containing glasses, which results in the formation of alkali element-depleted and -enriched phases. Formation of bubbles was only observed in the alkali element-containing iron phosphate and aluminophosphate glasses, not in sodium borosilicate glasses when irradiated over a broad of dose rates (1.6 × 1022c m-2s to 8 × 1026 e m-2. Separation of boron-rich phase from silicon-rich phase, iron-rich/aluminium-rich phase from phosphorous-rich domains were observed in the three types or glasses, respectively. Further irradiation resulted in formation of small particles. In Fe-containing borosilicate glasses, the Fe is associated with the boron-rich phases after phase separation. [ABSTRACT FROM AUTHOR]