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This memo introduces ion implantation processing. The introduction and background sections present applications that might be considered for ion implantation processing and give a brief description of the apparatus and the physical principles underlying the techniques. The entire process of ion beam processing is described to allow the reader to plan treatment parameters for parts and/or to double check treatment parameters recommended by vendors. This document provide workers in the field with a handbook of tables, graphs and equations that are needed for doing ion implantation processing. These include tables of ion ranges and straggling, formulae and tables which allow estimates to be simply made for sputtering coefficients, depth profiles of implanted elements, damage profiles, dose for sputter saturation of implanted profiles, temperatures reached by parts in vacuum during implantation, and estimates of the time and cost of ion implantation. Keywords: Ion implantation; Surface modification; Ion beam analysis; Ion beam processing; Corrosion; Ion Range; Sputtering; Materials processing; Applications of ion implantation; Wear; Straggling; Alloy formation; Tribology.

Thin films of substoiciometric silicon nitride were grown by the use of ion beam assisted deposition. The amorphous films were annealed at high temperatures (1017-1200C) to produce crystalline alpha-Si3N4. Both highly symmetric spherulitic crystal morphologies and irregular fractal aggregates were seen. In the latter case, a fractal dimension of 1.2 was measured. These two macroscopically different forms possessed correspondingly different microstructures. The morphologies were found to be determined by the temperature of the anneal., Prepared in collaboration with Illinois Univ., Urbana. Materials Research Lab.

There are two possible approaches to applying ion implantation to the modification of the corrosion behavior of metals and alloys. The first approach is to use ion implantation to produce metastable or amorphous corrosion-resistant surface alloys that are inaccessible by conventional metallurgical techniques, and to apply them to specific applications where corrosion is a severe problem. Secondly, and of a more fundamental nature, ion implantation can be used to introduce controlled amounts of various elements into the surface of a metal as part of a research effort to identify the mechanisms responsible for certain forms of general and localized corrosion. The technique of alloying to produce more corrosion resistant materials is widely used and the choice of a particular alloying element is usually based on the fact that it will enhance the formation of a passive film or will reduce the rate of the various cathodic processes that occur on the metal's surface., This article is from Proceedings of the Workshop on Ion Mixing and Surface Layer Alloying held April 15 & 16, 1983 at Pasadena, California, ADA131469, p136-149.

A program is currently underway to use ion implantation to improve the tribiological and corrosion characteristics of load bearing surfaces in both rolling element bearings and gears used in aircraft propulsion systems. This report describes that aspect of the program concerned with the use of ion implantation for surface alloying of bearing components in order to alleviate the problem of corrosion in M50 steel mainshaft aircraft engine bearings. (Author)

A preliminary study was made of the effect of various ions implanted in iron on the absorption of hydrogen by Ferrovac-E iron. Using the permeation technique, it was found that the location of implanted Pt, as modified by selective dissolution of iron from the surface, affects the kinetics of the hydrogen evolution reaction and, hence, of the hydrogen absorption process. The rate of hydrogen absorption decreased with increase in Pt concentration on the surface in both 0.1N NaOH and 0.1N H2SO4. A catalytic mechanism is proposed to explain the marked reduction in hydrogen permeation. There are no significant differences in the permeation behavior of unimplanted and helium- or iron-implanted iron membranes in 0.1N NaOH. The experimentally observed Tafel slope, the permeation-charging potential relationship, and the permeation-charging current relationship indicate a coupled discharge-recombination mechanism of hydrogen evolution on He-, Fe- or Pt-implanted iron. At higher cathodic overpotentials in 0.1N NaOH, corresponding to potentials more negative than -1.0V (SHE), another mechanism of hydrogen evolution is indicated. Selective dissolution of iron from the Pt-implanted Fe surface layer is indicated by Rutherford backscattering analyses to involve diffusion of Pt into the iron ahead of the receding surface. (Author)

The corrosion behavior of Pd implanted Ti in boiling 1 Molar sulfuric acid has been investigated by means of high resolution Rutherford backscattering (RBS) profiles of the Pd concentration as a function of corrosion time, and by electrochemical methods consisting of corrosion potential versus time curves and potentiostatic polarization data. Employing ion-implanted Xe as a surface 'marker,' absolute corrosion rates were determined by RBS analysis and compared to corrosion rates determined from the polarization curves. The rate of Ti dissolution is found to be reduced by about three orders-of-magnitude for Pd implanted samples. The corrosion potential-time curves and high resolution RBS data both show that soon after immersion, and Pd surface concentration rises to 20 atomic percent because of preferential dissolution of Ti and that the Pd is retained in the surface for corrosion time of up to 9 hr. The steady state corrosion potential of implanted samples is close to that of pure Pd and 800 mV anodic with respect to the corrosion potential of pure Ti. The protection is explained by the fact that the mixed electrode potential is more noble than the critical potential for passivity of Ti, resulting in a markedly reduced dissolution rate. (Author)

The U.S. Army Mobility Equipment Research and Development Center (MERDC), Fort Belvoir has been tasked by the Assistant Secretary of Defense (Installations and Logistics) with Energy Research and Development Administration (ERDA) funds to prepare a Department of Defense proposal for installing terrestrial solar photovoltaic power in DoD operational systems. This report describes a survey made by the Radiation Effects Branch of the Radiation Technology Division to identify specific terrestrial solar photovoltaic power applications appropriate to DoD operational systems and facilities.