FLUCTUATION OF INTERNAL FRICTION IN METALLIC GLASSES

Abstract

AbstractInternal friction (IF) of a metallic glass Zr55Cu30Al10Ni5 has been measured near the glass transition temperature Tg (= 666 K). The measurement is performed by using DMA (TA Instrument) apparatus at a frequency of 0.01 Hz for a specimen stabilized by annealing. The specimen is kept at a constant temperature T, and the IF value Q-1 is measured as a function of time t. A fluctuation of Q-1 with time is seen, and the magnitude of the fluctuation, F(t), is derived from the Q-1-vs-t data. F(t) is Fourier transformed to the frequency spectrum F(f). Such experiment and analyses are carried out at various temperatures near Tg. A characteristic peak (f ~ 10-3 Hz) is found in the spectrum F(f) in the glass transition region.