Radiation effects at the HfO2-MgO interface

A preliminary investigation into radiation effects at the HfO2-MgO interface, using classical molecular dynamics, is described. This composite system is representative of a dispersion nuclear fuel form concept being investigated for its potential in easing separations and reprocessing. During experiments involving ion bombardment of the interface a section of the top layer of HfO2 has been seen to break away, resulting in a large (about 10 μm) crater with a raised central region. Computer simulations, using molecular dynamics, have been carried out on three separate models in an attempt to understand this behaviour. The first model investigates single atom bombardment of the interface. Cascades involving clusters of atoms are also investigated and finally a model of delamination at the interface is considered.