Interfacial voids in aluminum created by aqueous dissolution

TitleInterfacial voids in aluminum created by aqueous dissolution
Publication TypeJournal Article
Year of Publication2010
AuthorsAdhikari S, Chumbley LS, Chen H, Jean YC, Geiculescu AC, Hillier AC, Hebert KR
Journal TitleElectrochimica Acta
Volume55
Pages6093-6100
Date Published8/1
ISBN Number0013-4686
Accession NumberISI:000280422800082
Keywordsaluminum, bubbles, corrosion, defects, hydrogen, metals, positron annihilation, positron-annihilation spectroscopy, pure aluminum, transmission electron microscopy, voids, WATER-VAPOR
Abstract

Nanometer-scale voids in aluminum formed by aqueous room-temperature corrosion were detected and characterized by a combination of electron microscopy techniques, atomic force microscopy, and positron annihilation spectroscopy. Void-containing layers were found within 100 nm of the metal surface, containing voids of 10-20 nm width with a number density of 10(8)-10(9) cm(-2). The voids were generated continuously during dissolution. The rapid nucleation and growth of voids suggest elevated concentrations of hydrogen-vacancy defects near the dissolving surface. Using the measured void radius and thickness of the void layer, the hypothesis that voids grow by vacancy condensation led to reasonable calculated values of the diffusion coefficient, and vacancy concentrations in agreement with independent estimates. (C) 2010 Elsevier Ltd. All rights reserved.

URL<Go to ISI>://000280422800082
DOIDoi 10.1016/J.Electacta.2010.05.073