DYNAMIC-MECHANICAL INVESTIGATIONS FOR STUDY OF DISLOCATION MOTION DURING PLASTIC FLOW

A double-resonator method for measuring the complex modulus (kHz-range) of a crystal during plastic flow in tensile or creep tests is described. The damping and modulus-defect of aluminum singlecrystals during plastic deformation at room temperature, particularly their dependence upon plastic strain, strain rate, frequency, and vibration amplitude, have been measured. Furthermore the influence of mechanical vibrations on the flow stress was investigated. A model is proposed and a theory described for the anelasticity of a crystal during plastic flow and the influence of a mechanical vibration superimposed on the plastic deformation. A comparison is made with the experimental results. © 1969.