Using DEFORM Software for Determination of Parameters for Two Fracture Criteria on DIN 34CrNiMo6

The aim of this study was to calibrate a material model with two fracture criteria that is available in the DEFORM software on DIN 34CrNiMo6. The purpose is to propose a type of simple test that will be sufficient for the determination of damage parameters. The influence of the quantity of mechanical tests on the accuracy of the fracture criterion was explored. This approach was validated using several tests and simulations of damage in a tube and a round bar. These tests are used in engineering applications for their ease of manufacturing and their strong ability to fracture. The prediction of the time and location of the failure was based on the parameters of the relevant damage model. Normalized Cockroft-Latham and Oyane criteria were explored. The validation involved comparing the results of numerical simulation against the test data. The accuracy of prediction of fracture for various stress states using the criteria was evaluated. Both fracture criteria showed good agreement in terms of the fracture locus, but the Oyane criterion proved more suitable for cases covering larger triaxiality ranges.

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Determination of a Rubber-Like Material Model as an Inverse Problem

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.70.225 ◽

2011 ◽

Vol 70 ◽

pp. 225-230 ◽

Cited By ~ 1

Author(s):

Agnieszka Derewonko ◽

Andrzej Kiczko

Keyword(s):

Selection Process ◽

Axial Stress ◽

Constitutive Models ◽

Material Model ◽

Polyester Fabric ◽

Point Of View ◽

Air Cushion ◽

Ill Conditioning ◽

Stress States

The purpose of this paper is to describe the selection process of a rubber-like material model useful for simulation behaviour of an inflatable air cushion under multi-axial stress states. The air cushion is a part of a single segment of a pontoon bridge. The air cushion is constructed of a polyester fabric reinforced membrane such as Hypalon®. From a numerical point of view such a composite type poses a challenge since numerical ill-conditioning can occur due to stiffness differences between rubber and fabric. Due to the analysis of the large deformation dynamic response of the structure, the LS-Dyna code is used. Since LS-Dyna contains more than two-hundred constitutive models the inverse method is used to determine parameters characterizing the material on the base of results of the experimental test.

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Numerical Modelling of Particulate Composite with a Hyperelastic Matrix

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.525-526.25 ◽

2012 ◽

Vol 525-526 ◽

pp. 25-28

Author(s):

Bohuslav Máša ◽

Luboš Náhlík ◽

Pavel Hutař

Keyword(s):

Numerical Modelling ◽

Damage Model ◽

Strain Curve ◽

Particulate Composite ◽

Material Model ◽

Particulate Composites ◽

The Finite Element Method ◽

Strain Energy Density Function ◽

The Matrix ◽

Good Agreement

The main aim of the paper is an estimation of the macroscopic mechanical properties of particulate composites using numerical methods. Matrix of the considered composite was cross-linked polymethyl methacrylate - PMMA in a rubbery state, which exhibits hyperelastic behaviour. The three parameter Mooney Rivlin material model, which is based on the strain energy density function, was chosen for description of the matrix behaviour. Alumina based particles (Al2O3) were used as a filler. Numerical modelling based on the finite element method (FEM) was performed to determine stress-strain curve of the considered particulate composite. Representative volume element (RVE) model was chosen for FE analyses as a modelling approach of a composite microstructure. Various geometry arrangements of particles and various directions of loading have been considered and composite anisotropy has been investigated. A good agreement between numerical calculations with damage model and experimental data has been found and the described method may have a great potential for numerical modelling of composite behaviour and design of new particulate composite materials.

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A Displacement Equivalence-Based Damage Model for Brittle Materials—Part II: Verification

Journal of Applied Mechanics ◽

10.1115/1.1599915 ◽

2003 ◽

Vol 70 (5) ◽

pp. 688-695 ◽

Cited By ~ 3

Author(s):

Y. Liu ◽

C. K. Soh ◽

Y. Dong ◽

Y. Yang

Keyword(s):

Biaxial Loading ◽

Damage Model ◽

Research Work ◽

Brittle Materials ◽

Preceding Paper ◽

Onsager Relations ◽

Proposed Model ◽

Uniaxial And Biaxial Loading ◽

Good Agreement

This paper focuses on the application of the damage model for brittle materials proposed in the preceding paper on theory. The evolution rule of damage derived using the Onsager relations is specified according to the experimental observation. The loading-unloading condition is discussed and the tangent modulus is derived. Then, the determination of the modal parameters is presented. For verification, the proposed model is applied to concrete under uniaxial and biaxial loading, and the numerical results are compared with those of other researchers and with the experimental results. The results are generally in good agreement and the proposed model is considered worthy for further research work.

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Simulation of cracks in wood using a coupled material model for interface elements

Holzforschung ◽

10.1515/hf.2007.053 ◽

2007 ◽

Vol 61 (4) ◽

pp. 382-389 ◽

Cited By ~ 26

Author(s):

Jörg Schmidt ◽

Michael Kaliske

Keyword(s):

Stress Component ◽

Damage Model ◽

Three Dimensional ◽

Path Following ◽

Material Model ◽

Timber Structures ◽

Wood Fibers ◽

Interface Elements ◽

Material Formulation

Abstract A three-dimensional anisotropic material model is presented that is applicable in combination with interface elements for simulation of the behavior of timber structures loaded in shear and tension perpendicular to the wood fibers. The material model can predict the stresses derived from the three-dimensional state of deformation. Determination of the algorithmic material tangent is shown. Computation of a stress component results from deformation in all directions. Furthermore, a damage model is implemented to simulate cyclic loading that yields a realistic unloading function for a cracked structure. In this case, a continuous-differentiable material formulation guarantees a robust path-following algorithm. A basic example is used to demonstrate the capability of the model to simulate the behavior of timber structures realistically and underlines the need for further research.

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Application of Coupled Ductile Fracture Criterion to Plane Strain Plates

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.382.186 ◽

2018 ◽

Vol 382 ◽

pp. 186-190 ◽

Cited By ~ 2

Author(s):

František Šebek ◽

Petr Kubík ◽

Jindřich Petruška

Keyword(s):

Aluminum Alloy ◽

Ductile Fracture ◽

Fracture Criterion ◽

Material Model ◽

Plastic Behavior ◽

Ductile Fracture Criterion ◽

User Subroutine ◽

Aa 2024 ◽

Stress States ◽

Subsequent Propagation

The paper presents a complex material model which covers the elastic-plastic behavior, material deterioration and ductile fracture. The calibration of such model was conducted for Aluminum Alloy (AA) 2024-T351 using specimens with various geometries and loading which covers various stress states. The model was then applied to the simulations of tensile test of plates. The computations were carried out in Abaqus/Explicit using the user subroutine Vectorized User MATerial (VUMAT), where the crack initiation and subsequent propagation was realized using the element deletion technique. The results were compared to the experimental observation in the end.

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Modeling of Fracture Behaviours of Ultrasonically Welded Cu-Cu Joints Under Different Loading Conditions

Volume 2B: Advanced Manufacturing ◽

10.1115/imece2015-53407 ◽

2015 ◽

Author(s):

Liang Xi ◽

Mihaela Banu ◽

S. Jack Hu ◽

Wayne Cai ◽

Teresa Rinker

Keyword(s):

Failure Modes ◽

Standard Procedure ◽

Lithium Ion ◽

Mechanical Tests ◽

Battery Pack ◽

Actual Behavior ◽

Modes Of Failure ◽

Lap Shear ◽

Good Agreement

A lithium-ion battery pack for electric vehicles may consist of several hundreds of battery cells joined together. Each cell contains joints of multiple thin sheets of electrodes of different conductive materials such as nickel coated copper, copper and / or aluminum. These within-cell and cell-to-cell joints must withstand static and dynamic mechanical loading. Determination of their maximum loading capacity is a very important task in order to predict the life of a battery pack. The standard procedure is to apply mechanical tests, such as lap shear and pull test to each joint. This procedure is time consuming and costly. There is a strong interest nowadays in developing validated models which can predict the actual behavior of the joints under different loadings and the associated failure modes. In this paper, two finite element models are developed to predict the strength of ultrasonically welded two-, three- and four layer joints of 0.2 mm thickness copper tabs with a 1mm thickness busbar. These models have the ability to predict three modes of failure of these joints depending on the weld quality, e.g., interfacial fracture, combined interfacial-circumferential fracture, and circumferential failure. These models are experimentally validated with very good agreement between experimental and predicted results.

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Cumulative Damage Model for Glass-Fiber Reinforced Composites under Two Blocks Loading

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.42.1 ◽

2019 ◽

Vol 42 ◽

pp. 1-9

Author(s):

Sid Ahmed Athmane ◽

Djebli Abdelkader ◽

Bendouba Mostefa ◽

Aid Abdelkrim ◽

Bachir Bouiedjra Belabbess

Keyword(s):

Nonlinear Models ◽

Damage Model ◽

Fatigue Curve ◽

Complex Nature ◽

Glass Fiber Reinforced ◽

Proposed Model ◽

Fatigue Damage Accumulation ◽

Damage Accumulation Model ◽

Determination Of Parameters

A fatigue damage accumulation model for composite materials is proposed. There is unanimity on the complex nature of the mechanisms of damage inherent to these types of materials. This led to proposals for nonlinear models, but relatively expensive in experimental requirements and determination of parameters. Thus, the proposed model is simple and does not require parameters apart the ultimate strength and the fatigue curve. A program is developed to allow the follow-up of the damage evolution during the cycles of loading. The proposed model is applied to E-Glass/Epoxy [0°/90°] under two blocks loading. Prediction results are relatively good and fit well with the experimental results compared to similar models.

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