Slow Atomic Motion in Zr-Ti-Cu-Ni-Be Metallic Glasses Studied by NMR
نویسندگان
چکیده
Nuclear magnetic resonance is used for the first time to detect slow atomic motion in metallic glasses, specifically, Be motion in Zr-Ti-Cu-Ni-Be bulk metallic glasses. The observations are not consistent with the vacancy-assisted and interstitial diffusion mechanisms and favor the spread-out free volume fluctuation mechanism for Be diffusion. Comparison with the results of Be diffusion measured by elastic backscattering the NMR results also indicates that the energy barriers for shortand long-range Be motion are the same. [S0031-9007(98)07917-4]
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