This grant investigates fundamentals of hydrogen atom interactions with defects in metals. Experimental techniques employed are small angle neutron scattering (SANS), transmission electron microscopy (TEM), large angle neutron scattering, and gamma ray diffraction. Recently it has been demonstrated that SANS can reveal directly the spatial profiles of the hydrogen isotope, deuterium, trapped at dislocations and grain boundaries in palladium. The dependency of the trapping strength on deuterium concentration, defect concentration, and temperature is examined using SANS. Determining the associated effects of impurity segregation, such as carbon and sulphur, at dislocations and grain boundaries is an integral part of this program. %%% This research adds to the knowledge base related to solute-defect interactions, important to mechanical and physical properties of metals and alloys.
