A novel micromechanics based damage model is proposed to address failure mechanism of defected solids with randomly distributed penny-shaped cohesive micro-cracks (Barenblatt–Dugdale type). Energy release contribution to the material damage process is estimated in a representative volume element (RVE) under macro hydrostatic stress state. Macro-constitutive relations of RVE are derived via self...

Degradation, damage evolution, and fatigue models in the literature for various engineering materials, mostly metals composites, are reviewed. For empirical established under framework of Newtonian mechanics, Gurson–Tvergaard–Needleman (GTN) type model, Johnson-Cook (J-C) microplasticity some other micro-mechanism based models, using irreversible entropy as a metric with an evolution function t...

Abstract In this paper, the Gurson-Tvergraad-Needleman (GTN) model is used to study damage of stainless steel springs at high temperatures. The basic material and GTN parameters are determined from stress-strain curves tensile tests. Then evolution 300 °C 900 analyzed based on finite element simulations. results show that below 600 °C, change volume fraction holes in spring, along with increase...

Based on meso-damage mechanics and finite element analysis, the aim of this paper is to describe the feasibility of the Gurson-Tvergaard-Needleman (GTN) constitutive model in describing the tensile behavior of corroded reinforcing bars. The orthogonal test results showed that different fracture pattern and the related damage evolution process can be simulated by choosing different material para...

In this paper, the initial and maximum load was studied using Finite Element Modeling (FEM) analysis during impact testing (CVN) of pipeline X70 steel. The Gurson-Tvergaard-Needleman (GTN) constitutive model has been used to simulate growth voids deformation steel at different temperatures. FEM simulations results study sensitivity with GTN parameters values proposed variation Finally, applied ...

Ductile tearing of a full size precracked pipe is experimentally investigated. In order to model and interpret the test, material characterized using smooth notched tensile bars C(T) specimens. This experimental database used fit parameters non local Gurson–Tvergaard–Needleman (GTN) proposed in Zhang et al. (2018) Chen (2020). The finite element simulations specific elements allowing for contro...

In this research the stress-strain curve of porous Titanium, as a common material for biomedical application, was predicted using the mechanical properties of fully solid Titanium experimental data. Modified Gurson model (Gurson-Tvergaard-Needleman (GTN) model) was used to predict the plastic response of porous Titanium in compaction. Different values of GTN parameters were used for different i...

This numerical investigation of an advanced Gurson–Tvergaard–Needleman(GTN) model is an extension of the original work of Ben Bettaieb et al. (2011). The model hasbeen implemented as a user-defined material model subroutine (VUMAT) in the Abaqus/explicitFE code. The current damage model extends the previous version by integrating the threedamage mechanisms: nucleation, growth an...

Tube spinning is an effective plastic-forming technology for forming light-weight, high-precision and high-reliability components in high-tech fields, such as aviation and aerospace. However, cracks commonly occur in tube spinning due to the complexity of stress state, which severely restricts the improvement of the forming quality and forming limit of components. In this study, a finite elemen...

A unified experimental-computational study on ductile fracture initiation and propagation during small punch testing is presented. Tests are carried out at room temperature with unnotched disks of different thicknesses where large-scale yielding prevails. In thinner specimens, the fracture occurs with severe necking under membrane tension, whereas for thicker ones a through thickness shearing m...