Showing papers by "David Bacon published in 1987"

Characterization of heavy-ion damage in ruthenium

Abstract: Displacement-cascade collapse to form vacancy loops is of fundamental importance to the development of damage structures in irradiated metals. In the present experiments, displacement cascades have been generated in ruthenium, a high melting-point hexagonal metal with a c/a ratio of 1.58, by irradiation with heavy ions having a range of masses and energies. A detailed transmission electron microscopy analysis of the vacancy loops formed by cascade collapse has shown that four distinct sets of loop geometries are present. In a majority of cases the cascades collapse initially on to the {1010} prism planes to form loops with Burgers vector b=½〈1010〉 and it is shown that these can subsequently unfault to form perfect ⅓ 〈1120〉-type loops. When the incident-ion-beam direction lies in the basal plane, a minority of the cascades collapse on to the basal planes to form faulted ½[0001] loops and these can transform to a lower-energy faulted loop with b of the type ⅙〈2023〉. From determination of the loop s...