A viscoplastic model, whose descriptive and predictive capabilities with respect to the unidirectional deformation of metallic materials had already been demonstrated, was extended so as to cover the case of cyclic loading. The constitutive equations which were proposed were motivated by microstructural considerations, especially with regard to a channel-like dislocation structure which was characteristic of cyclic deformation. However, it was felt that the concept of a recoverable immobilized dislocation density which it introduced was applicable to a wider range of dislocation structures. A good agreement between the model, and the experimental data for 2 metallurgically entirely different alloys, substantiated the claim.

A Dislocation Density Based Constitutive Model for Cyclic Deformation. Y.Estrin, H.Braasch, Y.Brechet: Journal of Engineering Materials and Technology, 1996, 118[2], 441-7