Bordoni Relaxation and Microplasticity in Aluminium

The Bordoni relaxation in f.c.c. metals is generally attributed to the thermally activated formation of kink pairs (Seeger-Paré model). From the peak features, a Peierls-Nabarro stress value can be deduced. The existence of such a PN stress should control the plastic deformation: nevertheless the studies of variation of the macroscopic elastic limit show that this variation is associated with an intersection mechanism. In fact, the study of the microdeformation and anelastic limit in the temperature range of Bordoni relaxation show that the dislocation motion is first controlled by the existence of the PN stress.