Mechanical spectroscopy of nanocrystalline nickel near room temperature

In this study, the anelastic behavior of nanocrystalline nickel was investigated by mechanical spectroscopy. Test temperature ranged from room temperature to 415 K, and frequency from 235 to 2567 Hz, with two internal friction peaks observed. Peak temperature increased with increasing frequency, indicating a thermally activated damping process. The smaller peak yields an activation energy H = 0.70 eV. The peaks appear to be Pβ and Pγ Hasiguti peaks, arising from damping due to dislocations and point defects.