The pitting behavior of Al-3103 implanted with molybdenum

The pitting corrosion of Al-3103 (AI-Mn alloy) implanted with molybdenum was investigated in solutions containing 0.1 M NaCl using potentiodynamic polarization tests. The Mo ion implantation in Al-3103 was performed with ion energies from 50 to 100 keV at doses ranging from 5 x 10(16) to 2 x 10(17) ions/cm(2). The Mo depth profiles were measured by Rutherford backscattering spectrometry, Polarization tests were performed in the presence and absence of a bicarbonate (HCO3-)/carbonate (CO32-) buffer. Compared to the unimplanted ones, the implanted samples showed an increase of corrosion potentials from 170 to 240 mV in the unbuffered solution and ail increase of pitting potentials From 90 to 160 mV in the buffered solution. The surface chemical states and corrosion morphology of the samples were analyzed by X-ray photoelectron spectroscopy and scanning electron microscopy, respectively. (C) 2000 Elsevier Science Ltd. All rights reserved.