INVESTIGATION OF THE NONLINEAR ELASTIC PROPERTIES OF METALS BY A VIBRATION METHOD

A method is proposed for determining the nonlinearity parameters of th e stress-strain curve of metals in the microplasticity region, based o n the dependence of the resonance shift, the variation of the reciproc al quality factor Q-1, and the second- and third-harmonic amplitudes o n the vibration amplitude of the mechanical oscillatory circuit formed by a metal rod sample loaded with weights at both ends. A phenomenolo gical model of the stress-strain curve of a metal is proposed for inte rpreting the observed nonlinear effects.