Title  Fundamental and applied experimental investigations of corrosion of steel by LBE under controlled conditions: kinetics, chemistry morphology, and surface preparation	Researchers A. Johnson, J. Farley, D. Perry Collaborators Ning Li, LBE Project Leader, Los Alamos National Laboratory Peter Hosemann, Visiting Scientist, Los Alamos National Laboratory Eric P. Loewen, Idaho National Engineering and Environmental Laboratory
Background  Advanced nuclear processes and facilities (e.g., transmutation of nuclear waste, fast reactors, and spallation neutron sources) impose special demands on materials, which must withstand high temperatures, high radiation fields, and chemical corrosion. Proposed schemes for transmuting nuclear waste require a non-moderating coolant such as lead-bismuth eutectic (LBE). While LBE corrodes most steels, small amounts of oxygen in the LBE greatly reduces the corrosion rate, and could ideally re-grow a damaged oxide layer in-situ. The protective oxide layer would thus be self-healing. However, the fundamental understanding of the role of oxygen and passivating oxide layers is presently incomplete.	Research Objectives and Methods Steel samples have been characterized before and after exposure to LBE using different types of surface microscopy, including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX), Wavelength Dispersed X-ray, X-ray Photoelectron Spectrometry (XPS), and Sputter Depth Profiling. In past work, steel samples exposed to LBE at the Institute for Physics and Power Engineering in Obninsk, Russia, were examined using SEM and EDX. Samples with the same chemical composition but different surface treatments were compared, and cold-rolled samples were more corrosion resistant than annealed samples. Increased corrosion resistance was associated with changes in oxide layer thickness, morphology, and composition. These past results were published in the Journal of Nuclear Materials.  During the present reporting period, gas-phase experiments were conducted, in which steel samples were oxidized in glass capsules at elevated temperatures in a tube furnace.  Corroded steel samples were analyzed from a variety of sources, including the Delta loop at LANL and samples corroded at UNLV in the gas phase experiments.
Students  Dan Koury G Brian Hosterman G Umar Younas G Thao Trung Ho G Jenny Welch U Tim Lane U	Department Chemistry
Final Report	Annual Report
Proposal 04/01/04	Quarterly Reports  07/01/04 -10/30/04 10/01/04-12/31/04 01/01/05-03/31/05 01/01/06-03/31/06