In order to investigate the influence of defects and their chemical surroundings, polished and annealed samples of pure Mg and AZ31 alloy (3Al-1wt%Zn) were irradiated with Zn, Al and Mg ions. The energy of the ions was between 1.4 and 3.0MeV according to 2.3µm mean implantation depth. Firstly, Doppler-broadening measurements as a function of the positron implantation energy as well as lateral position with a resolution of 2 mm were recorded in order to image the irradiated area on the sample. Secondly, coincident Doppler-broadening spectra were measured at different positron penetration depths according to the Makhovian profile, which clearly showed strong deviations depending upon the ion type of the irradiated samples. The relation between elemental signature and defect concentration in the sample was discussed.

Characterization of the Chemical Vicinity of Open Volume Defects in Magnesium and AZ31 with Coincident Doppler Broadening Spectroscopy. M.Stadlbauer, C.Hugenschmidt, K.Schreckenbach: Physica Status Solidi C, 2007, 4[10], 3489-92