Direct observation of microstructural changes in ion-beam modified ceramics

Abstract

A technique for the direct observation of microstructural changes in ceramics following ion- implantation is presented. Ion-implantation produces modifications to the mechanical properties of ceramic surfaces. These modifications have been investigated as a means of improving the hardness and wear of such materials. Examples of these changes will be presented for single-crystal specimens of MgO which have been implanted with Xe+ ions. The resultant microstructural changes are a function of ion fluence and are related to structural modifications at or near the surface.Transmission electron microscopy (TEM) is a powerful technique for examination of microstructure on a nanometer scale. A problem often encountered when conventional methods of specimen preparation, for TEM analysis, are used is the possibility of ion-beam induced damage. Ion-beam damage can be a serious problem especially in the preparation of MgO specimens. In the present study damage resulting from ion-milling can be entirely avoided by ion-implantation directly into an electron-transparent thin-foil specimen.