A Nuclear Magnetic Resonance and Transmission Electron Microscopic Studyof Moving Dislocations in Ternary Al-Base Alloys

Abstract

Pulsed nuclear magnetic resonance proved to be a complementary new technique for the study of moving dislocations in Al-Mg-Zn alloys. The NMR technique, in combination with transmission electron microscopy have been applied to study dislocation motion in A1-0.6 at% Mg-1 at% Zn and Al-1.2 at% Mg-2.5 at% Zn. From the motion induced part of the spin-lattice relaxation rate the mean jump distance of mobile dislocations has been determined as a function of strain. From the NMR data it is concluded that moving dislocations advance over a number of solute atoms in these alloys as described by Mott-Nabarro's model.