Internal friction of dislocations in a magnetic field

A theory is proposed for the influence of a magnetic field on the amplitude-independent internal friction of dislocations in metals. The theory combines the electron viscous-drag model with the possibility of the dislocation depinning from the paramagnetic centers. The theory is compared with the experimental data obtained in undeformed and deformed copper. Excellent agreement is achieved in deformed metals. For undeformed metals the agreement is good for low magnetic fields. A modulation technique is proposed that will improve greatly the precision of the measurement of the dislocation parameters.