Studies of oxide growth on some aluminum, magnesium, and magnesium alloy surfaces under ambient exposure conditions

The objective of this work was to understand the oxide growth rate and mechanism under the conditions where pure aluminum, magnesium and alloys of magnesium were exposed to ambient atmospheres at 22{dollar}spcirc{dollar}C and 100{dollar}spcirc{dollar}C for periods up to 168 hours. The study complements earlier investigation in this laboratory where some of the same pure metals were exposed to Langmuir-scale quantities of H{dollar}sb2{dollar}O. The surface products were analyzed by XPS and their thicknesses were determined by using inelastic mean free path calculations.; The growth as a function of time was able to be related to previous measurements of the reaction of H{dollar}sb2{dollar}O with clean aluminum and magnesium at much lower pressures.; SIMS studies were employed to examine the segregation of minor and trace elements in the oxide film of the magnesium alloys, in order to understand the mechanisms oxide growth.; Atomic Force Microscopy (AFM) and Scanning Electron Microscopy were used to study changes in the topographical features of the oxide films during exposure for 24 hours and 168 hours. (Abstract shortened by UMI.)...