The sliding element can have a yield stress (σ y) that is strain rate dependent, or even constant, as shown in Figure 1c. In the figure E is the modulus of elasticity, λ is the viscosity parameter and N is a power-law type parameter that represents non-linear dashpot. Plasticity can be accounted for by adding sliding frictional elements as shown in Figure 1. Rate-dependence can be represented by nonlinear dashpot elements in a manner similar to viscoelasticity. The elastic response of viscoplastic materials can be represented in one-dimension by Hookean spring elements. The main difference between rate-independent plastic and viscoplastic material models is that the latter exhibit not only permanent deformations after the application of loads but continue to undergo a creep flow as a function of time under the influence of the applied load. Rate-dependent plasticity is important for transient plasticity calculations. The inelastic behavior that is the subject of viscoplasticity is plastic deformation which means that the material undergoes unrecoverable deformations when a load level is reached. Rate-dependence in this context means that the deformation of the material depends on the rate at which loads are applied. Viscoplasticity is a theory in continuum mechanics that describes the rate-dependent inelastic behavior of solids. Elements used in one-dimensional models of viscoplastic materials.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |