MAGNETOPLASTIC EFFECT IN NONMAGNETIC CRYSTALS AND INTERNAL-FRICTION

A new physical phenomenon, the magnetoplastic effect, was found and in vestigated in a series of non-magnetic crystals (NaCl, CsI, LiF, Zn, A l). The phenomenon manifests itself in dislocation displacements as a result of exposing the specimens to a static magnetic field in the abs ence of mechanical loading. The effect was studied experimentally as a function of the time of magnetic treatment of the samples, the magnit ude and orientation of the magnetic field (B = 0.05-2 T), the temperat ure (T = 4.2-293 K), the type and concentration of impurities, the den sity of ''forest'' dislocations and the frequency (v = 0-200 Hz) of th e alternating (over orientation) magnetic field. A strong effect of a weak static electric field (E = 2-30 V cm(-1)) on the dislocation mobi lity in NaCl specimens simultaneously exposed to a static magnetic fie ld (B = 0.1-0.4 T) is found (with no electric influence at B = 0). A p hysical interpretation of the phenomenon is proposed. Possible manifes tations of the magnetoplastic effect in the internal friction are disc ussed.