DISLOCATION RELAXATION PEAKS IN MOLYBDENUM

In high purity molybdenum single crystals measurements of the damping and modulus are reported in the temperature range of the α and γ-relaxation. Activation volumes of the α-subpeaks were determined from the amplitude dependence of the Internal Friction. The results clearly support the explanation of the α-relaxation in terms of kink pair fromation in 71°-dislocations and diffusion of different types of geometrical kinks in screw dislocations. Deformation induced point defects interact with these dislocation segments giving rise to the β-relaxation. Some characteristics of the γ-peak (kink pair formation on screw dislocations) are discussed