\ub2\u2077Al and \u2077Li spin-echo and spin-echo double resonance NMR applications to the study of lithium depletion and surface oxidation in Al-Li alloy

The physical properties and the near-surface microstructures of Al\u2013Li alloys are known to be affected by thermo-mechanical processes during alloy manufacture. The research reported here explored \ub2\u2077Al and \u2077Li 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 Li\u2082CO\u2083 and the minor oxide compound is LiAlO\u2082;, which is formed at higher temperatures. LiAlO\u2082 is shown to be formed in spatially confined clusters on the surface of the Li-depleted, Al-rich near-surface layer. Copyright \ua9 2001 John Wiley & Sons, Ltd.NRC publication: Ye