INTERNAL FRICTION PHENOMENA CONNECTED WITH EITHER EDGE OR SCREW DISLOCATIONS IN GERMANIUM

Internal friction measurements were carried out on germanium specimens with either edge or screw dislocations. The Kessler peak and logarithmic trend were checked with the edge character specimens. The screw character specimens showed two new peaks and another logarithmic stage, all characterized by low activation energies. A logarithmic dependence of the peak temperature on the dislocation density was also observed. Under certain conditions, regarding the kink distance dependence on dislocation density and on pinning lengths, the results concerning the screw dislocations may be interpreted in terms of smooth kink-free motion while the edge dislocation phenomena can be explained on the basis of damping mechanisms depending on interactions between either kinks and dragging points or point defects and dislocations. © 1969 The American Institute of Physics.