The past 20 years have seen substantial work on the modeling of ductile damage and fracture. Several factors explain this interest. (i) There is a growing demand to provide tools which allow to increase the efficiency of structures (reduce weight, increase service temperature or load, etc.) while keeping or increasing safety. This goal is indeed first achieved by using better materials but also by improving design tools. Better tools have been provided which consist (ii) of material constitutive equations integrating a physically-based description of damage processes and (iii) of better numerical tools which allow to use the improved constitutive equations in structural computations which become more and more realistic. This article reviews the material constitutive equations and computational tools, which have been recently developed to simulate ductile rupture.

/pdf/continuum-models-of-ductile-fracture-a-review-35khqjinf0.pdf

Continuum Models of Ductile Fracture: A Review

The past 20 years have seen substantial work on the modeling ofductile damage and fracture Several factors explain this interest (i) There is agrowing demand to provide tools which allow to increase the efficiency of structures(reduce weight, increase service temperature or load, etc) while keeping or increasingsafety This goal is indeed first achieved by using better materials but also byimproving design tools Better tools have been provided which consist (ii) of materialconstitutive equations integrating a physically-based description of damage processesand (iii) of better numerical tools which allow to use the improved constitutiveequations in structural computations which become more and more realistic Thisarticle reviews the material constitutive equations and computational tools, whichhave been recently developed to simulate ductile ruptureKEY WORDS: ductile rupture, models, numerical simulation INTRODUCTION P REDICTIVE NUMERICAL SIMULATIONS of ductile fracture may be ofgreat interest in industrial situations for which full-scale experimentalapproaches are either too costly or even impracticable This is the case ofductile tearing of gas pipelines over several hundred meters, of crackpropagation in large nuclear vessels or of ductile tearing of aircraft fuselageFor such applications, simulations should predict crack paths, stability,stress states, etc Several techniques may be used to achieve these objectivesThe approach based on Rice (1968) J-integral is widely used for industrialapplications but suffers from various limitations: (i) It can only deal withpreexisting cracks and cannot be applied to model crack initiation and pro-pagation from a notch (ii) It is not a material intrinsic property asit stronglydepends on specimen geometry as experimentally shown in Sumpter and

https://hal.archives-ouvertes.fr/hal-00142084/document

Ductile to brittle transition of an A508 steel characterized by Charpy impact test: Part I: experimental results

https://dash.harvard.edu/bitstream/handle/1/4211043/Xue_CalibrationProcedures.pdf?sequence=2

Calibration procedures for a computational model of ductile fracture

Modeling of plane strain ductile rupture

A micromechanical model of ductile damage by void nucleation, growth and coalescence is widely and successfully applied to describe phenomena of ductile tearing. The model’s fundamental principles, and especially the constitutive equations of Gurson, Tvegaard and Needleman (GTN-model), are briefly described. Some of the material parameters of the GTN-model are calibrated by performing cell model calculations, which is a method of determining the structural behaviour of a single void in a plastic material. The approach is used to study the dependence of material strength and toughness on microstructural features of nodular cast iron. The numerical simulations were realized within the FE-program ABAQUS by a user-supplied material model.

Micromechanical modelling of damage and fracture of ductile materials

Six different Al-Al 3 Ti composites were prepared via the powder metallurgy route. The size and volume fraction of Al 3 Ti particles was varied for a systematic investigation of fracture behaviour. The dominant failure mechanism in the composites is particle fracture and void growth starting from the broken particles. In comparison with the pure Al-matrix, an incorporation of Al 3 Ti particles reduces the crack initiation toughness and reduces the slope of the crack growth resistance curve. The inter-particle distance was found to be the main microstructural parameter controlling the slope of the crack growth resistance curve. The modified Gurson-Tvergaard-Needleman model (GTN model) was applied to one of the composites. The behaviour of tensile specimens could be successfully modelled, whereas the experimentally observed crack propagation in precracked single edge bend specimens [SE(B)] could not be simulated with the GTN model.

Steglich

Papers

Micromechanical modelling of damage and fracture of ductile materials

INFLUENCE OF PARTICLE SIZE AND VOLUME FRACTION ON DAMAGE AND FRACTURE IN Al–Al3 Ti COMPOSITES AND MICROMECHANICAL MODELLING USING THE GTN MODEL