Application of the thin layer activation technique to study surface erosion under high voltage electrical spark discharges

The thin layer activation technique using a heavy ion beam has been applied to measure the erosion loss of materials by electrical spark discharges with a discharge current in the mA range. Since the range of heavy ions such as 14N, 16O and 20Ne, is about one order less than that of light ions such as p, d and α, the total activity can be generated within a narrow layer by activation with heavy ions. In the present work, a narrow layer of activity of ∼27 μm thickness was produced in copper-based materials by heavy ion induced nuclear reactions using 110 MeV 16O ions to measure the surface erosion in the range of hundreds of nanometers to few microns. The sensitivity can be enhanced to tens of nanometers using suitable heavy ions.