This award will support collaborative research between Prof. David Seidman of Northwestern University, and Dr Georges Martin of the Centre d'Etudes de Chimie Metallurgique, Vitry-sur-Seine, France, on the chemistry which occurs on a microscopic scale in ion-beam-induced solid-state reactions. The objective of this research is to increase our understanding of how the loss of energy of the ion beam (represented in a displacement cascade (DC) of target atoms) to the target crystal affects reactions on the scale of three to ten lattice constants; the investigators will also study how these reactions, are in turn affected by ambient temperature. By modifying ambient temperature and incoming ion energy and flux, and analyzing the results, information about micro-chemical reactions relevant to larger-scale systems, such as concentrated alloys, may be obtained. The researchers will carry out this study, using the atom-probe field-ion microscope (APFIM), largely developed by the U.S. investigator at Northwestern University. This instrument will permit the non-destructive measurement of the chemistry of individual DC's, created at the surfaces of special test structures. Results will be analyzed with the French collaborator, who is a leading theoretician in the area of the modelling of micro-chemical reactions. The results of this research could have impact in the field of metallurgy, in which highly concentrated alloys can be formulated with unique properties.
