TEM-MICROSTRUCTURAL INVESTIGATIONS OF ION-BEAM MODIFIED CERAMICS WITHRESPECT TO THEIR MACROSCOPIC PROPERTIES

The high costs for production, surface finishing, sensitivity against fracture, and unsatisfactory friction behaviour are the main problems for broader applications of engineering ceramics. Ion beam techniques are universal methods for basic research with respect to doping, surfa ce treatment and coating, and a potential method for generating materi als with specific surface properties. Transmission electron microscopy (TEM) is a suitable technique for understanding the results of four-p oint bending tests and dynamic hardness measurements of Ar or Ti impla nted polycrystalline Si3N4. It was possible to characterize the transf ormations of the Si3N4 grains and the surrounding binder phases caused by ion implantation and to obtain information on the stability of the modified material.