A non-linear uniaxial integral constitutive equation incorporating rate effects, creep and relaxation

摘要: Abstract A previously proposed first order non-linear differential equation for uniaxial viscoplasticity, which is in stress and strain but linear rates, transformed into an equivalent integral equation. The employs total only symmetric with respect to the origin applies tension compression. limiting behavior large strains times monotonic, creep relaxation loading investigated appropriate limits are obtained. When specialized overstress model it qualitatively shown reproduce key features of viscoplastic behavior. These include: initial elastic or viscoelastic response: immediate slope a instantaneous change rate normal sensitivity spacing stress-strain curves obtained at various rates; primary secondary such that (relaxation) do not cross. Isochronous also considered. Other specializations yield wavy inverse sensitivity. For cyclic must be modified account history dependence sense plasticity.