THEORY OF NONLINEAR ANELASTIC INTERNAL-FRICTION PEAKS .2. THEORY OF THE INTERNAL-FRICTION PEAKS ASSOCIATED WITH LONGITUDINAL AND TRANSVERSECORE DIFFUSION (P-0, P-1('), P-1('') PEAKS)(2))

On the basis of the dislocation kink atmosphere model, the relaxation time and the relaxation strength associated with the longitudinal and transverse core diffusion of solute atoms under quasi-static stress ha ve been computed by solving the diffusion equation. It was found that the relaxation time and the relaxation strength are nonlinear with res pect to the applied stress. Analytical expressions for internal fricti on and modulus defect associated with longitudinal and transverse core diffusion were obtained by assuming the relaxation process to be near ly of Debye type with nonlinear relaxation time and relaxation strengt h. The manifestations of the theoretical internal friction curves vers us temperature and strain amplitude conform to experimental results.