Download or read book Microstructural Modeling and Computational Homogenization of the Physically Linear and Nonlinear Constitutive Behavior of Micro heterogeneous Materials written by Felix Fritzen and published by KIT Scientific Publishing. This book was released on 2014-08-22 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Engineering materials show a pronounced heterogeneity on a smaller scale that influences the macroscopic constitutive behavior. Algorithms for the periodic discretization of microstructures are presented. These are used within the Nonuniform Transformation Field Analysis (NTFA) which is an order reduction based nonlinear homogenization method with micro-mechanical background. Theoretical and numerical aspects of the method are discussed and its computational efficiency is validated.

Download or read book Microstructural Modeling and Computational Homogenization of the Physically Linear and Nonlinear Constitutive Behavior of Micro heterogeneous Materials written by Felix Fritzen and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microstructure generation and micromechanical modeling of sheet molding compound composites written by Görthofer, Johannes and published by KIT Scientific Publishing. This book was released on 2022-09-13 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wir präsentieren einen Algorithmus zur schnellen Erzeugung von SMC Mikrostrukturen hoher Güte, durch Verwendung einer exakten Schließung und eines quasi-zufälligen Samplings. Darüber hinaus stellen wir ein modulares Framework zur Modellierung anisotroper Schädigung vor. Unser Konzept der Extraktionstensoren und Schädigungsfunktionen ermöglicht die Beschreibung komplexer Vorgänge. Darüber hinaus schlagen wir einen ganzheitlichen Multiskalenansatz zur Bestimmung anisotroper Versagenskriterien vor. - We introduce an algorithm that allows for a fast generation of SMC composite microstructures. An exact closure approximation and a quasi-random orientation sampling ensure high fidelity. Furthermore, we present a modular framework for anisotropic damage evolution. Our concept of extraction tensors and damage-hardening functions enables the description of complex damage-degradation. In addition, we propose a holistic multiscale approach for constructing anisotropic failure criteria.

Download or read book Homogenization and materials design of mechanical properties of textured materials based on zeroth first and second order bounds of linear behavior written by Lobos Fernández, Mauricio and published by KIT Scientific Publishing. This book was released on 2018-07-09 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Finite element simulation of dislocation based plasticity and diffusion in multiphase materials at high temperature written by Albiez, Jürgen and published by KIT Scientific Publishing. This book was released on 2019-05-22 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: A single-crystal plasticity model as well as a gradient crystal plasticity model are used to describe the creep behavior of directionally solidi?ed NiAl based eutectic alloys. To consider the transition from theoretical to bulk strength, a hardening model was introduced to describe the strength of the reinforcing phases. Moreover, to account for microstructural changes due to material ?ux, a coupled diffusional-mechanical simulation model was introduced.

Download or read book Efficient fast Fourier transform based solvers for computing the thermomechanical behavior of applied materials written by Wicht, Daniel and published by KIT Scientific Publishing. This book was released on 2022-10-11 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanical behavior of many applied materials arises from their microstructure. Thus, to aid the design, development and industrialization of new materials, robust computational homogenization methods are indispensable. The present thesis is devoted to investigating and developing FFT-based micromechanics solvers for efficiently computing the (thermo)mechanical response of nonlinear composite materials with complex microstructures.

Download or read book A dynamic and statistical analysis of the temperature and fatigue behavior of a race power unit The effect of different thermodynamic states written by Hölz, Peter and published by KIT Scientific Publishing. This book was released on 2020-07-08 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biaxial Characterization and Mean field Based Damage Modeling of Sheet Molding Compound Composites written by Schemmann, Malte and published by KIT Scientific Publishing. This book was released on 2018-11-09 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermomechanical Mean Field Modeling and Experimental Characterization of Long Fiber Reinforced Sheet Molding Compound Composites written by Kehrer, Maria Loredana and published by KIT Scientific Publishing. This book was released on 2019-06-13 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: A discontinuous fiber-reinforced thermoset material produced by the Sheet Molding Compound process is investigated. Due to the process-related fiber orientation distribution, a composite with an anisotropic microstructure is created which crucially affects the mechanical properties. The central objectives are the modeling of the thermoelastic behavior of the composite accounting for the underlying microstructure, and the experimental characterization of the pure resin and the composite material.

Download or read book Modeling of Dislocation Grain Boundary Interactions in Gradient Crystal Plasticity Theories written by Erdle, Hannes and published by KIT Scientific Publishing. This book was released on 2022-07-12 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: A physically-based dislocation theory of plasticity is derived within an extended continuum mechanical context. Thermodynamically consistent flow rules at the grain boundaries are derived. With an analytical solution of a three-phase periodic laminate, dislocation pile-up at grain boundaries and dislocation transmission through the grain boundaries are investigated. For the finite element implementations, numerically efficient approaches are introduced based on accumulated field variables.

Download or read book Modeling martensitic phase transformation in dual phase steels based on a sharp interface theory written by Ruck, Johannes and published by KIT Scientific Publishing. This book was released on 2021-05-07 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: artensite forms under rapid cooling of austenitic grains accompanied by a change of the crystal lattice. Large deformations are induced which lead to plastic dislocations. In this work a transformation model based on the sharp interface theory, set in a finite strain context is developed. Crystal plasticity effects, the kinetic of the singular surface as well as a simple model of the inheritance from austenite dislocations into martensite are accounted for.

Download or read book Two Scale Thermomechanical Simulation of Hot Stamping written by Neumann, Rudolf and published by KIT Scientific Publishing. This book was released on 2017-10-27 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hot stamping is a hot drawing process which takes advantage of the polymorphic steel behavior to produce parts with a good strength-to-weight ratio. For the simulation of the hot stamping process, a nonlinear two-scale thermomechanical model is suggested and implemented into the FE tool ABAQUS. Phase transformation and transformation induced plasticity effects are taken into account. The simulation results regarding the final shape and residual stresses are compared to experimental findings.

Download or read book A Gradient Crystal Plasticity Theory Based on an Extended Energy Balance written by Prahs, Andreas and published by KIT Scientific Publishing. This book was released on 2020-09-15 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: An overview of different methods for the derivation of extended continuum models is given. A gradient plasticity theory is established in the context of small deformations and single slip by considering the invariance of an extended energy balance with respect to Euclidean transformations, where the plastic slip is considered as an additional degree of freedom. Thermodynamically consistent flow rules at the grain boundary are derived. The theory is applied to a two- and a three-phase laminate.

Download or read book Homogenization of the Linear and Non linear Mechanical Behavior of Polycrystals written by Katja Jöchen and published by KIT Scientific Publishing. This book was released on 2014-05-13 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work is dedicated to the numerically efficient simulation of the material response of polycrystalline aggregates. Therefore, crystal plasticity is combined with a new non-linear homogenization scheme, which is based on piecewise constant stress polarizations with respect to a homogeneous reference medium and corresponds to a generalization of the Hashin-Shtrikman scheme. This mean field approach accounts for the one- and two-point statistics of the microstructure.

Download or read book Micromechanical Finite Element Simulations of Crack Propagation in Silicon Nitride written by Johannes Wippler and published by KIT Scientific Publishing. This book was released on 2014-07-28 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon nitride is used for challening applications like cutting inserts or forming rolls. The extreme strength and toughness of the material is achieved by an interaction between the microstructure and fracture behaviour on the microlevel. In order to understand these mechanisms, detailed unit cells have been defined and used for the determination of the effective fracture properties. The results have been used for the implementation of an effective continuum damage mechanics model.

Download or read book Fiber Orientation Tensors and Mean Field Homogenization Application to Sheet Molding Compound written by Bauer, Julian Karl and published by KIT Scientific Publishing. This book was released on 2023-02-27 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effective mechanical properties of fiber-reinforced composites strongly depend on the microstructure, including the fibers' orientation. Studying this dependency, we identify the variety of fiber orientation tensors up to fourth-order using irreducible tensors and material symmetry. The case of planar fiber orientation tensors, relevant for sheet molding compound, is presented completely. Consequences for the reconstruction of fiber distributions and mean field homogenization are presented.

Download or read book A computational multi scale approach for brittle materials written by Ernesti, Felix and published by KIT Scientific Publishing. This book was released on 2023-04-17 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials of industrial interest often show a complex microstructure which directly influences their macroscopic material behavior. For simulations on the component scale, multi-scale methods may exploit this microstructural information. This work is devoted to a multi-scale approach for brittle materials. Based on a homogenization result for free discontinuity problems, we present FFT-based methods to compute the effective crack energy of heterogeneous materials with complex microstructures.