| AVS 60th International Symposium and Exhibition | |
| Atom Probe Tomography Focus Topic | Wednesday Sessions |
| Session AP+AS+EM+MI+TF-WeM |
| Session: | APT Analysis of Semiconductor, Magnetic, and Oxide Materials |
| Presenter: | J.V. Ryan, Pacific Northwest National Laboratory |
| Authors: | D.K. Schreiber, Pacific Northwest National Laboratory J.V. Ryan, Pacific Northwest National Laboratory J.J. Neeway, Pacific Northwest National Laboratory S. Gin, CEA Marcoule, France |
| Correspondent: | Click to Email |
Atom probe tomography (APT) is being used to study the corrosion and alteration layers formed in borosilicate glass samples during long-term (1–26 years) water corrosion. The water environment and glass composition (SON68 – the non-activated surrogate of the French nuclear waste form R7T7 glass) were selected to generate novel insights into the rate-limiting mechanisms of glass corrosion that are relevant to the long-term storage of high-level nuclear waste in a geologic repository. APT concentration profiles across the corroded/pristine glass interface reveal significantly different interfacial widths for B and Na (~2-5 nm) than for Li and H (~15-30 nm), which suggests that multiple element-specific degradation mechanisms are occurring in parallel. Furthermore, the measured interfacial widths are much sharper than were measured previously by energy-filtered transmission electron microscopy and NanoSIMS. Accurate compositional APT analysis of this 26-component complex glass is, however, quite difficult. The implications of these findings and also practical considerations and limitations when performing these experiments will be discussed in some detail.