Author: Jessica PapasideroPublisher:
ISBN:
Category :
Languages : en
Pages : 147
Book Description
Experimental and Numerical Analysis of Ductile Fracture Under Multiaxial Loading
Author: Jessica PapasideroNumerical Analysis of Ductile Fracture Experiments Using Single-Edge Notched Tension Specimens
Author: T. HollsteinPublisher:
ISBN:
Category : Elastic compliance
Languages : en
Pages : 8
Book Description
The elastic compliance C and the J-integral are investigated for single-edge notched tension specimens. The parameters are discussed with respect to crack length, thickness of specimen, load level, stress state, and loading system. Test results for a structural steel St E 460 (nickel-vanadium) at room temperature are presented together with two- and three-dimensional finite element calculations for some of these specimens. The overall specimen behavior including J for the 10-mm-thick specimens is reproduced by a plane stress model. Even the 40-mm-thick specimens are better modelled in plane stress than in plane strain. The strong influence of the angular stiffness of the loading system on the specimen behavior is demonstrated. For the experimental arrangement used in this study a single-specimen estimation procedure is developed to calculate J from the work done on the specimen.
Hybrid Experimental-numerical Determination of the Loading Path to Fracture in TRIP780 Sheets Subjected to Multi-axial Loading
Author: Matthieu DunandPublisher:
ISBN:
Category :
Languages : en
Pages : 116
Book Description
(Cont.) A first series of fracture experiments is carried out on three types of full-thickness fracture specimens. This experimental program characterizes the onset of fracture for stress states between uniaxial tension and equi-biaxial tension. An effort is made to quantify and minimize the errors affecting the hybrid experimental-numerical analysis of those experiments. Inaccuracies affecting the stress triaxiality and plastic strain histories to fracture are evaluated by comparing surface strains measured by Digital Image Correlation (DIC) and computed by Finite Element Analysis (FEA). A second series of fracture experiments is carried out on a newly designed butterfly-shaped specimen, which allows for multi-axial testing under combinations of normal and tangential loads. Experiments for four different loading conditions are performed and used to analyze the onset of fracture for stress states ranging from pure shear to transverse plane strain tension.
Experimental and Numerical Analysis on the Dynamic Fracture in Brittle Cylinders Under Thermal Loading
Author: Weijing HeDuctile Fracture in Metal Forming
Author: Kazutake KomoriPublisher: Academic Press
ISBN: 0128147733
Category : Technology & Engineering
Languages : en
Pages : 294
Book Description
Ductile Fracture in Metal Forming: Modeling and Simulation examines the current understanding of the mechanics and physics of ductile fracture in metal forming processes while also providing an approach to micromechanical ductile fracture prediction that can be applied to all metal forming processes. Starting with an overview of different ductile fracture scenarios, the book then goes on to explain modeling techniques that predict a range of mechanical phenomena that can lead to ductile fracture. The challenges in creating micromechanical models are addressed alongside methods of applying these models to several common metal forming processes. This book is suitable for researchers working in mechanics of materials, metal forming, mechanical metallurgy, and plasticity. Engineers in R&D industries involved in metal forming such as manufacturing, aerospace, and automation will also find the book very useful. Explains innovative micromechanical modeling techniques for a variety of material behaviors Examines how these models can be applied to metal forming processes in practice, including blanking, arrowed cracks in drawing, and surface cracks in upset forging Provides a thorough examination of both macroscopic and microscopic ductile fracture theory
AN EXPERIMENTAL STUDY OF DUCTILE FAILURE UNDER MULTI-AXIAL LOADING.
Author: Numerical Methods in Fracture Mechanics
Author: Numerical Methods in Fracture Mechanics
Author: Anthony Roger LuxmoorePublisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 696
Book Description
Ductile Fracture at Intermediate Stress Triaxialities
Author: Matthieu DunandPublisher:
ISBN:
Category :
Languages : en
Pages : 256
Book Description
Accurate predictions of the onset of ductile fracture play an increasingly important role in the design of lightweight sheet metal structures. With the development of virtual prototyping practices, most transportation vehicles are now computer-engineered in great detail before launching their mass production, thereby requiring reliable models for plasticity and fracture. This thesis reports on a comprehensive investigation into the effect of stress state on the onset of ductile fracture of an Advanced High Strength Steel (AHSS), covering development of new experimental procedures, material characterization and phenomenological as well as micro-mechanical modeling of the onset of fracture. Based on an extensive multi-axial experimental program, the anisotropic plasticity of the present material is described by a non-associated quadratic anisotropic model. Comparison of model predictions to experimental results reveals that the proposed model provides better predictions than associated isotropic or anisotropic quadratic models. Moreover, a structural validation is presented that demonstrates the higher prediction accuracy of the non-associated plasticity model. A hybrid experimental-numerical approach is proposed to investigate the dependence of the onset of fracture to stress state. The experimental program covers the complete range of positive stress triaxialities, from pure shear to equibiaxial tension. It includes different full thickness specimens as well as multi-axial fracture experiments where combinations of tension and shear loadings are applied to a newly developed butterfly-shaped specimen. Loading paths to fracture are determined for each experiment in terms of stress triaxiality, Lode angle parameter and equivalent plastic strain and show a non-monotonic and strong dependence of ductility to stress state. The extensive fracture characterization is used to evaluate the predictive capabilities of two phenomenological and physics-inspired fracture models (the Modified Mohr-Coulomb and a shear-modified Gurson model) that take the effect of the first and third stress tensor invariants into account in predicting the onset of fracture. Finally, a micro-mechanical model relating the onset of fracture to plastic localization into a narrow band at the micro-scale is developed. The effect of stress state on localization is investigated numerically by means of a 3D void-containing unit cell submitted to well-controlled and proportional loadings in the macroscopic stress state. Based on simulation results, an analytical localization criterion is proposed which defines an open convex envelope in terms of the shear and normal stresses acting on the plane of localization and correlates well with experimental results.
Numerical Methods in Fracture Mechanics
Author: Anthony Roger LuxmoorePublisher:
ISBN:
Category : Mathematics
Languages : en
Pages : 908
Book Description