Intense ion beams for surface treatment applications

Summary form only given. Intense pulsed ion beams have been be used to achieve a rapid melt and resolidification (RMR) of the surface layer of metals, ceramics, and silicon. This leads to enhancements in wear durability and corrosion resistance. RMR treatment has been applied both to simple alloys and alloys onto which a thin-film coating has been applied. The beam then mixes this coating into the substrate. The nature of beam-induced effects depends upon the treatment ion(s). In particular, heavier beam ions (e.g. N, Kr, Xe) produce a smoother surface topography compared to proton treatment. We report on experiments aimed at optimizing beam parameters from these heavier ions. Alloys and bi-metal combinations were treated on the RHEPP-I facility at Sandia National Laboratories (0.5 MV, up to 0.5 us at sample location, <10 J/cm/sup 2/). Ions are generated by the MAP (Magnetically confined Anode Plasma) gas-breakdown ion source operated in a magnetically insulated ion diode. The typical ion range for singly-ionized N is 1 /spl mu/m Numerical modeling of thermal histories neglecting ablation have yielded predictions consistent with diagnostic measurements of treated samples. Treated samples have been characterized by scanning electron microscopy (SEM), Rutherford Backscattering Spectrometry (RES), X-Ray Diffraction (XRD), cross-sectional Transmission Electron Microscopy (XTEM), and electrochemical corrosion tests.