Hybrid gas-metal co-implantation with a modified vacuum arc ion source

Energetic beams of mixed metal and gaseous ion species can be generated with a vacuum arc ion source by the addition of gas to the are discharge region under appropriate conditions. This operational mode could prove to be an important tool for ion implantation research by providing a method for forming buried layers of mixed composition such as, for example, metal oxides and nitrides. In work to-date, we have formed a number of mixed metal-gas ion beams including Ti + N, Pt + N, Al + O and Zr + O. The particle current fractions of the metal-gas ion components in the beam ranged from 100% metallic to approximately 80% gaseous depending on the operational parameters, We have used this new variant of the vacuum are ion source to carry out some exploratory investigations of the effect of Al + O and Zr + O co-implantation on the tribological characteristics of stainless steel. Here we describe the ion source modifications, the species and charge state composition of the hybrid beams produced, and the results of some preliminary investigations of the surface modification of stainless steel by co-implantation of mixed aluminum/oxygen or zirconium/oxygen ion beams

The psychometric study of risk perception

53 pagesThe writing of this paper was supported by the National Science Foundation under Grant PRA-8116925 to Perceptronics, Inc