Oxidation studies on small atom doped TI*5*SI*3*

: This research arose from an effort to bridge the research of solid state chemists and material scientists. For several years, researchers at Ames Laboratory have been investigating an interesting class of binary intermetallic materials that have a demonstrated ability to incorporate substantial quantities of ternary additions while maintaining the structure of the host material. This ability arises from the presence of interstices within the Mn5Si3-type structure of the host binary intermetallic which can accommodate a wide variety and amount of ternary elements. This research demonstrated marked effects on the structure of the host material, namely, changes in lattice constants and bond lengths as determined by careful structural studies. With the realization that these additions may also significantly affect material properties, a window of opportunity was presented to utilize this "doping" effect and determine the potential engineering usefulness of these materials. Approximately 175 binary intermetallic compounds are known to exist in the Mn5Si3 structure, and considering the substantial number of possible ternary alloying elements which could be added, one is presented with an overwhelming number of material systems for investigation. Fortunately from an engineering point of view, this field can be significantly narrowed by considering some of the critical material properties required for a particular type of application.