PLASTIC-DEFORMATION OF AMORPHOUS SOLIDS BY TRACK OVERLAP

Particle tracks in solids are the sources of mechanical stresses and strains. These stresses lead to macroscopically visible plastic deformation of amorphous materials when the particle tracks are well-aligned and overlap each other. The anisotropy of the irreversible deformation is determined by the track symmetry; the sample dimensions perpendicular to the tracks grow linearly with increasing fluence whereas the sample dimension along the tracks shrinks. This effect occurs in all amorphous solids, ranging from high-purity vitreous silica to metallic glasses but not in crystalline solids. The dependence of this plastic deformation on electronic stopping power, irradiation temperature, and various solid-state parameters will be discussed. The findings emphasize the importance of structural relaxation for a deeper understanding of particle track formation.