Effect of alloying addition of Pr on the dissolution rate of melt-spun Mg in 3% NaCl solution

Abstract

Melt-spun Mg-1 and 15 wt% Pr binary alloys were immersed in a 3% NaCl solution saturated with Mg(OH)2 for up to 72 h. The dissolution rate was evaluated by hydrogen evolution method. Surface characterization of the pristine and corroded surfaces has been carried out using X-ray photoelectron spectroscopy (XPS), secondary ion mass spectroscopy (SIMS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surfaces of both the pristine and corroded samples were found to consist mainly of Mg(OH)2 and MgO. However, results of XRD and SEM showed that the dominant product formed on the corroded sample was Mg(OH)2. SIMS depth profiling showed that there was a depletion of Pr at the surfaces of Mg-Pr samples. © 1998 Chapman & Hall.