Showing papers in "International Journal of Plasticity in 1993"

TL;DR: In this paper, a set of kinematic hardening rules for simulating rachetting behavior is presented, where each component has a critical state for its dynamic recovery to be activated fully.

TL;DR: In this article, a tensorial internal state variable model of the evolving anisotropic polymer response was developed to predict the response of polycarbonate and polymethylmethacrylate over a range of strain rates and temperatures.

TL;DR: In this article, the kinematic hardening rules formulated in Part I of this work (i.e., Models I and II) are applied to ratchetting experiments of Modified 9Cr-1Mo steel done by Tanaka et al. as well as to a nonproportional experiment of OFHC copper by Lamba and Sidebottom.

TL;DR: In this paper, a new a priori stability for the full nonlinear systems of coupled thermoplasticity at finite strains was described and a fractional step method leading to a new class of unconditionally stable staggered algorithms.

TL;DR: In this paper, a deformation theory of plasticity is proposed where the deformation paths for material elements are assumed and the plastic work becomes dependent on displacements, and a mathematical description of a constitutive law of deformation plasticity based on this path for rigid-plastic and for elastoplastic materials is developed.

TL;DR: In this article, a finite element method is used to solve for the three-dimensional deformation of a plastic workpiece, where the elemental constitutive response is derived from the microstructural response of a polycrystal aggregate situated in the element.

TL;DR: In this paper, a concrete constitutive equation of metals with isotropic-kinematic hardening and tangential plasticity is formulated, which is capable of describing the general loading behavior including nonproportional, reverse loading, and reloading.

TL;DR: In this paper, a pre-oriented polycarbonate (PC) has been subjected to various magnitudes of pre-orientation via uniaxial compression, and the subsequent anisotropic yield and post yield behavior is then experimentally determined, also by compression.

TL;DR: In this paper, the condition of continuity in the large and in the small and Masing effect as the mechanical requirements for cyclic plasticity are first formulated, and the basic characteristics of several well-known and frequently used cyclic deformation models are examined with respect to fulfillment of these requirements, and their inevitable defects are indicated.

TL;DR: In this paper, a metric for the strain rate potential for plastically deforming metals is defined in six-dimensional deviatoric strain rate space, and its gradient provides deviateic stresses in the flowing material.

TL;DR: In this paper, a viscoplastic theory is developed that reduces analytically to creep theory under steady-state conditions and becomes plasticity theory at its rate-independent bound.

TL;DR: In this article, an augmented localization tensor is developed for elastoplastic constitutive behavior that describes discontinuous bifurcation at the constitutive level, and an auxiliary condition is encountered that restricts the jump of the stress rate to remain symmetric across discontinuity surfaces of second order.

TL;DR: In this paper, a strain hardening model for the plastic deformation of rate-dependent FCC polycrystals is proposed based on experimental observations previously reported for single crystals, which is an extension of that employed by Peirce et al. [1983] and includes both the selfhardening and latent hardening of the slip systems.

TL;DR: In this paper, the influence of the von Mises and Tresca equivalent offset strains on the subsequent yield surfaces is studied. But this was not the case when large von-Mises offset strains were used, and the corresponding subsequent yield surface passed through the Von Mises loading surface.

TL;DR: In this article, the stress-strain rate relations for an anisotropic, incompressible viscous body that is orthotropic, transversely isotropic, are drawn from symmetry considerations.

TL;DR: In this paper, a new approach for cyclic viscoplastic problems is described, which is an iterative procedure that accounts for the whole loading process in a single time increment.

TL;DR: In this paper, the plastic potential and yield function of a porous material containing either aligned or randomly oriented spheroidal voids are developed at a given porosity and pore shape.

TL;DR: In this paper, the diversity of monotonic, cyclic, and viscous mechanical properties of an austenitic 17-12 Mo-SPH stainless steel in the intermediate temperature domain: 20 ⩽ T ⩾ 700° C, and for unidirectional or bidirectional loadings, both in and out of phase.

TL;DR: In this paper, a viscoplastic-damage type of constitutive theory for high strain-rate flow processes and ductile fracture is used to model the deformation and fracture of dynamically loaded smooth cylindrical tensile bars.

TL;DR: In this article, a phenomenological constitutive model for fibrous composite materials with a ductile matrix is postulated incorporating damage mechanics with micromechanical behavior, which is first formulated in an undamaged composite system and then transformed consistently achieved in terms of an overall damage tensor M for the whole composite.

TL;DR: In this article, a viscoplastic constitutive model for simulating the behavior of Hastelloy-X single crystal material was derived based on crystallographic slip theory, and the results of the model were used to determine the appropriate constitutive constants and to test the predictions.

TL;DR: In this paper, a fully nonlinear shakedown analysis is considered for structures undergoing large elastic-plastic strains, and path-dependent and pathindependent shakedown theorems are presented that can be realized in an incremental step-by-step procedure using Finite Element codes.

TL;DR: In this paper, the growth of wrinkles in the finite deformation process is incrementally and numerically determined by a thin shell finite element in a convected coordinate system based on Hill's variational principle for elastic-plastic solids, a modification of Love-Kirchhoff postulates and a quasiconforming element technique.

TL;DR: In this paper, a self-consistent relation with a weakening constraint power in the matrix is derived for the primary and steady-state creep of polycrystals, under which the constraint power of the creeping matrix is found to decrease exponentially with the ratio of the elastic shear modulus to the secant creep modulus.

TL;DR: In this paper, the problem of strain localization into planar bands of rate-independent elastoplastic solids with smooth yield surface and plastic potential was analyzed, and it was shown that strain localization with elastic unloading on one side of the band first becomes possible either at localization in the comparison solid corresponding to the loading branch of the constitutive equation or at the snap-back threshold.

TL;DR: In this paper, the authors derived a rate-type constitutive law based on the proposed yield function for a porous metal and made a comparison between yield loci derived from the yield function and those determined from an FE model.

TL;DR: In this paper, a nonlocal theory based upon crystalline plasticity is developed from which a non-local constitutive equation at the grain level is derived for nonlocal inhomogeneous materials by the self-consistent approximation.

TL;DR: In this paper, a phenomenological formulation is proposed for each of the mechanisms in question, integrated in modular form into the context of a unified viscoplastic model, formulated for an extended temperature range, allowing the description of a large variety of behaviors observed between 20° and 700°C.

TL;DR: The mechanisms that may lead to plastic instabilities are reviewed briefly, and their intimate connection with localization of plastic shear is emphasized in this article, where the combination of macro and micro experiments, i.e., analysis of stress fluctuations and serrations, and of slip and shear band evolution during deformation, for investigations of these mechanisms is demonstrated with examples of LUDERS and PORTEVIN-LeCHATELIER band propagation in single glide oriented crystals.

TL;DR: In this paper, the extremal path of an endochronic constitutive equation without using a yield surface is found, which makes plastic work act as a potential such that the deviatoric stress can be derived from its derivative with respect to plastic strain.