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A microstructural study was performed on zirconium, copper and titanium implantation in single and polycrystalline lumina to enhance the latter's mechanical properties using grazing incidence x-ray diffraction. The results, after implantation of a low dose of ions, revealed no modification on the general x-ray spectrum of polycrystalline alumina. Higher doses, on the other hand, effectuated the relaxation of the lattice deformation through various phenomena, depending on the implanted ion.

Implantation of nitrogen into thin iron films containing carbon ions by preimplantation reveals the occurrence of a carbon and nitrogen rearrangement due to iron carbonitride evolution at 250 degrees Celsius. For temperatures exceeding 300 degrees Celsius, the epsilon-carbonitride phase is unstable due to the inability of gamma-Fe4N to hold carbon atoms. The instability of the epsilon-carbonitride phase results in the elimination of the rearrangement process and the formation of definite nitrogen and carbon atom profiles.

The study of ceramics is tackled from the space-charge physics point of view. The role of the polarization and relaxation mechanisms is demonstrated for friction coefficient and wear, as well as for breakdown voltage, therefore these characteristics depend on the permittivity. This approach is based on experiments performed with pure or X-irradiated single crystal alumina (sapphire) or polycrystalline alumina. A new method (mirror method) is presented in which the possibility of creating trapped electrical charges in a given material is measured using the electron beam of a scanning electron microscope X-ray irradiation changes permittivity, Young modulus and charging properties. These changes can modify both the irradiated and the unirradiated areas. Friction, and consequently machining, create defects everywhere in the material i.e. inside as well as outside the contact or wear tracks.

The correlated spin glass model helps understand the magnetic behavior of thin films of transition metals given by ferromagnetic resonance and SQUID magnetization measurements. Fe films subject to Mossbauer spectra at zero field show 20% of iron around the Fe grains. This is present as a thin nonmagnetic oxide skin. Ni films exhibit a reduced atomic moment. A cluster deposition at low energy gives these films. Deposition of neutral clusters gives a cuboctahedron structure in Ni films, while Co(n) and Fe(n) clusters exhibit icosahedral structure.