Résumé | The physical properties and the near-surface microstructures of Al–Li alloys are known to be affected by thermo-mechanical processes during alloy manufacture. The research reported here explored ²⁷Al and ⁷Li spin-echo and spin-echo double resonance NMR to follow the structural changes that accompany lithium depletion and oxidation processes at the alloy surface. The NMR analysis generally agrees with conclusions reached previously using other analytical methods. The major oxide compound generated is Li₂CO₃ and the minor oxide compound is LiAlO₂;, which is formed at higher temperatures. LiAlO₂ is shown to be formed in spatially confined clusters on the surface of the Li-depleted, Al-rich near-surface layer. Copyright © 2001 John Wiley & Sons, Ltd. |
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