The Bordoni internal friction peak in copper

Abstract

The internal friction of cold-worked single crystals and polycrystalline specimens of high-purity copper has been measured in the temperature range from 20 to 200 K at frequencies between 10 and 25 kHz. The Bordoni peak was found to occur at approximately the same temperature for crystals of <111> and <100> orientations as for polycrystalline specimens. It was displaced to a slightly higher temperature for crystals of <110> orientation, but this shift is attributed to the fact that smaller stresses were used in the prior deformation of these specimens; the peak in these crystals is relatively broad and asymmetric. Thus these results at kilohertz frequencies do not show the orientation dependence of the Bordoni peak which has been observed by other authors at megahertz frequencies.

The Bordoni internal friction peak in silver single crystals

“…Specimen A, which had its axis in the (1 11) direction and had been extended 5 % with a resolved shear stress of 30 N "-2, showed a Bordoni peak at a temperature of 62 K at a frequency of 17.0 kHz. The peak is similar in shape to that for a similar crystal of copper (Brown and Niblett 1973), which is typical of specimens after appreciable prior deformation. The internal friction is higher for specimen B, which had its axis 64' off the (1 10) direction.…”

“…Extrapolation of these graphs into the kilohertz frequency range suggests that a strong orientation dependence of the temperature of the peak should also occur at these frequencies. However, Mongy et a1 (1964) found a similar orientation dependence at megahertz frequencies for a copper single crystal, whereas our measurements on copper single crystals (Brown and Niblett 1973) showed that the temperature of the peak was essentially independent of the orientation at kilohertz frequencies, although small shifts occurred for some crystals which had been deformed with low stresses. The Bordoni peak in gold single crystals behaves in a similar manner: Mongy (1965) found orientation dependence in the megahertz frequency range which was not observed by Grandchamp (1971) at kilohertz frequencies.…”

“…The internal friction of each crystal was measured at its fundamental longitudinal resonant frequency (in the range 13-18 kHz) at temperatures between 20 and 160 K. The maximum strain amplitudes used were less than 10-7, and no amplitude dependence of the internal friction was observed. The measurement technique was similar to that previously described (Brown and Niblett 1973).…”

The bordoni peak in silver single crystals at megahertz frequencies

“…However, in comparison with extensive results obtained from studying the Bordoni peak in copper single crystal [9,[17][18][19] and in aluminium single crystal [10][11], one can believe that our conclusion is valid i.e. However, in comparison with extensive results obtained from studying the Bordoni peak in copper single crystal [9,[17][18][19] and in aluminium single crystal [10][11], one can believe that our conclusion is valid i.e.…”

The ultrasonic Bordoni peak in copper crystals and the kink picture

“…This problem is now resolved, the relaxation time becoming very important in equation (9). In figure 5 we show an Arrhenius plot with peak temperatures assembled for copper from [1,[20][21][22][23][24][25][26][27][28][29][30][31] and those obtained by us for high temperatures and for low temperatures in samples cut from the same crystal batch [4,32]. The peak temperatures in this plot run from 50 K to 170 K covering the lowest and the highest peak temperatures achieved from Bordoni peaks.…”