Abstract
High energy ion irradiation is an emergent process to modify material surface. This irradiation results in implantation of foreign atoms as well as displacement of atoms in material surface layer at low temperatures at which the diffusion of atoms is limited.The ion irradiation often generates a metastable amorphous phase in the surface layer. The ion irradiation also generates high residual compressive stress in the surface layer. The amorphous and compressively stressed layer is demonstrated to be beneficial to improvement of mechanical properties of ceramics. During post-irradiation thermal-annealing, implanted foreign atoms coalesce each other to make metal particles, and react with matrix atoms to make compounds. These are also shown to modify magnetic, optical and other properties of materials.
