Formulation and Implementation of a New Porous Plasticity Model

A new rate independent porous plasticity model is proposed for the modeling of ductile damage initiation due to void growth in metallic materials. The model is based on a simple yield description which includes two porosity functions that affect both deviatoric and hydrostatic stress evolution. The current version of the model predicts damage solely due to void growth and it should be extended to include the void initiation and coalescence criteria. The numerical examples study the performance of the developed model for the evolution of porosity through unit cell calculations and for the necking of a uniaxial tensile bar. The preliminary void growth calculations in the unit cell study is acceptable at triaxiality values below 1. (C) 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( Peer-review line: Peer-review under responsibility of the 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers.


Application of Continuum Damage Mechanics in discontinuous crack formation: Forward extrusion chevron
Soyarslan, Celal; TEKKAYA, AHMET ERMAN; Akyüz, Uğurhan (2008-06-01)
Materializing Continuum Damage Mechanics (CDM), numerical modeling of discrete internal cracks, namely central bursts, in direct forward extrusion process is presented. Accordingly, in a thermodynamically consistent setting, a local Lemaitre variant damage model with quasi-unilateral evolution is coupled with hyperelastic-plasticity. The formulations are constructed in the principal axes where simultaneous local integration schemes are efficiently developed. To this end, the framework is implemented as ABAQ...
Development of a Micromechanics Based Cohesive Zone Model and Application for Ductile Fracture
Yalçınkaya, Tuncay; Tandoğan, İzzet Tarık (2019-01-01)
In this paper, derivation and implementation of a micromechanically motivated traction separation law for cohesive zone modeling of ductile fracture is discussed. The formulation of the framework is based on the growth of pores in an array of representative volume elements where pores are idealized as cylinders. Two relations are derived under normal and shear loading for mode-I and mixed-mode respectively, based on the upper bound for a perfectly plastic material (Yalcinkaya and Cocks (2015), Yalcinkaya an...
Vibration of beams with multiple open cracks subjected to axial force
Binici, Barış (Elsevier BV, 2005-10)
A new method is proposed to obtain the eigenfrequencies and mode shapes of beams containing multiple cracks and subjected to axial force. Cracks are assumed to introduce local flexibility changes and are modeled as rotational springs. The method uses one set of end conditions as initial parameters for determining the mode shape functions. Satisfying the continuity and jump conditions at crack locations, mode shape functions of the remaining parts are determined. Other set of boundary conditions yields a sec...
Physics Based Formulation of a Cohesive Zone Model for Ductile Fracture
Yalçınkaya, Tuncay (2015-07-01)
This paper addresses a physics based derivation of mode-I and mode-II traction separation relations in the context of cohesive zone modeling of ductile fracture of metallic materials. The formulation is based on the growth of an array of pores idealized as cylinders which are considered as therepresentative volume elements. An upper bound solution is applied for the deformation of the representative volume element and different traction-separation relations are obtained through different assumptions.
Hybrid finite element for analysis of functionally graded beams
Sarıtaş, Afşin; Soydas, Ozan (2017-01-01)
A hybrid finite element model is presented, where stiffness and mass distributions over a beam with functionally graded material (FGM) are accurately modeled for both elastic and inelastic material responses. Von Mises and Drucker-Prager plasticity models are implemented for metallic and ceramic parts of FGM, respectively. Three-dimensional stress-strain relations are solved by a general closest point projection algorithm, and then condensed to the dimensions of the beam element. Numerical examples and veri...
Citation Formats
T. Yalçınkaya, C. Erdoğan, and İ. T. Tandoğan, “Formulation and Implementation of a New Porous Plasticity Model,” 2019, vol. 21, Accessed: 00, 2020. [Online]. Available: