论文部分内容阅读
Inteal friction of nanocrystalline nickel is investigated by mechanical spectroscopy from 360 K to 120 K.Two relaxation peaks are found when nanocrystaJline nickel is bent up to 10% strain at room temperature and fast cooling.However, these two peaks disappear when the sample is annealed at room temperature in vacuum for ten days.The occurrence and disappearance of the two relaxation peaks can be explained by the interactions of partial dislocations and point defects in nanocrystalline materials.