抄録
High energy ion irradiation is an emergent process to modify materials surface. This irradiation results in implantation of foreign atoms as well as many displacements of atoms in a materials surface layer at low temperatures at which the diffusion of atoms is limited. So, the ion irradiation often generates metastable amorphous phase in the surface layer. The ion irradaition also generates high residual compressive stress in the surface layer. The amorphous layer and the compressively stressed layer are demonstrated to be beneficial to improvement of mechanical properties of ceramics. Ion beam mixing also causes improvement of adhesion strength of a metal thin film on ceramics. Ion beam mixed ceramics are found to have high resistivity against abrasive wear.