Applications of Ion Beam Analysis Techniques to Erosion Studies

Proton induced x-ray emission (PIXE), ion implantation and combined Rutherford backscattering (RBS) and nuclear reaction (NR) analyses have been used in studies of hot gas erosion of steel surfaces. Three experiments will be discussed. (1) Steel nozzles were exposed to the erosive flows of a variety of burning propellants. Concentrations and depth profiles of carbon, nitrogen and oxygen in the exposed surfaces were obtained by combined RBS 4nd NR analyses. The results are discussed in terms of the erosive properties of the propellants. (2) Two steel samples were implanted with nitrogen to investigate a possible improvement in wear characteristics when exposed to burning propellants. The sample implanted with 1 MeV nitrogens produced a small, but possibly significant, improvement in the wear. (3) Propellant combustion products expelled through a steel nozzle have been collected on rotating aluminum strips. PIXE analysis of the strips permits elemental identifications as well as the measurement of the time-of-expulsion profiles.