Ion Beam and Plasma Technology Development for Surface Modification at Los Alamos National Laboratory

摘要

We are developing two high-throughput technologies for materials modification. The first is a repetitive intense ion beam source for materials modification through rapid surface melt and resolidification (up to 10(sup 10) deg/sec cooling rates) and for ablative deposition of coatings. The short range of the ions (typically 0.1 to 5 micrometers) allows vaporization or melting at moderate beam energy density (typically 1-50 J/cm(sup 2)). A new repetitive intense ion beam accelerator called CHAMP is under development at Los Alamos. The design beam parameters are: E=200 keV, I=15 kA, (tau)=1 (micro)s, and 1 Hz. This accelerator will enable applications such as film deposition, alloying and mixing, cleaning and polishing, corrosion and wear resistance, polymer surface treatments, and nanophase powder synthesis. The second technology is plasma source ion implantation (PSII) using plasmas generated from both gas phase (using radio frequency excitation) and solid phase (using a cathodic arc) sources. We have used PSII to directly implant ions for surface modification or as method for generating graded interfaces to enhance the adhesion of surface coatings. Surfaces with areas of up to 16 m(sup 2) and weighing more than a thousand kilograms have been treated in the Los Alamos PSII chamber. In addition, PSII in combination with cathodic source deposition has been used to form highly adherent, thick Er(sub 2)O(sub 3) coatings on steel for reactive metal containment in casting. These coatings resist delamination under extreme mechanical and thermal stress.