IN-SITU INVESTIGATION OF THE EFFECT OF A MAGNETIC-FIELD ON THE MOBILITY OF DISLOCATIONS IN DEFORMED KCL-CA SINGLE-CRYSTALS

This paper presents the results of an experimental investigation into the mobility of edge dislocations in KCI:Ca single crystals and the ef fect of a static magnetic held of 0,3 T on the dislocation mobility. T he experiments on the effect of a magnetic field on the dislocation mo bility were carried out with the use of a high-resolution (1 ms) metho d that permits in situ measurements of the sample dipole moment induce d by the motion of charged dislocations as the crystal is being deform ed, It is found that the starting stress is reduced in a magnetic fiel d and the activation volume for overcoming of point defects by the dis locations is increased. It is further found that the magnetic field in creases the rate of motion of the dislocations at the initial stage of deformation (to the point of dislocation multiplication) but has no e ffect on the mobility in the multiplication stage. (C) 1997 American I nstitute of Physics.