CURRENT TOPICS OF ION-BEAM RESEARCH-AND-DEVELOPMENT

The use of directed energetic ion beams to improve the surface-sensitive properties of materials has been pursued worldwide for almost two decades. In that time, numerous examples of property improvements have been demonstrated in the laboratory and some applications are currently finding commercial uses. Among these current topics of transitional R&D are nitrogen ion implantation to impart wear resistance to precision components, including titanium alloy surgical prostheses and selected tooling. The hybrid combination of ion beam bombardment in conjunction with physical vapor deposition, commonly termed ion-beam-assisted deposition (IBAD), has emerged as a powerful processing technique. It combines many of the positive attributes of ion beam and conventional coating technologies, such as high density, superior adhesion and the ability to produce arbitrarily thick coatings. An important feature of IBAD technology is its frequently demonstrated ability to control many generic properties of coatings, such as the morphology, adhesion, residual stress and stoichiometry. Current applications of ion beam processing for the production of wear-, corrosion- and fatigue-resistant surfaces are presented here with an emphasis on those pertaining to US Army needs.