Surface modification by ion chemical and physical erosion

Physical and chemical ion erosion surface interactions are observed for various elements and composite materials such as Si, B, C, TiB₂, WCCo cermet, and stainless steel which have been bombarded by low energy (50–1800 eV) hydrogen ions. Extrapolations of hydrogen erosion yields to zero hydrogen ion energy indicate that compounds or elements which are capable of forming volatile compounds with hydrogen undergo selective removal from surface and near surface regions. Auger depth profiling indicates that carbon can be selectively removed from near surface regions of cemented carbides and carburized stainless steel. Similarly, boron can be selectively removed from TiB₂. The results of this study may be extended to a variety of materials in which surface composition modifications are of interest.