Analysis of process-induced distortions and residual stresses of composite structures

Analysis of process-induced distortions and residual stresses of composite structures
Author: Christian Brauner
Publisher: Logos Verlag Berlin GmbH
Total Pages: 168
Release: 2013
Genre: Science
ISBN: 3832535284

The increased application of composite materials in lightweight structures leads to new integral design of structural parts, using the example of, an integral composite landing flap of an Airbus A320 aircraft. This offers possibilities to simplify the process chain, to decrease manufacturing costs and to have fibre fair structural design. The critical disadvantage of large integral designs is that process-induced deformations are a risk factor during the design phase of the manufacturing process, because rework is not always possible. Especially, the aircraft industry with its demands on high qualities / tolerances and the application of hot curing resin systems, requires knowledge-based methods for virtual process design to avoid time- and effort-consuming iterations. This thesis contributes to the understanding of the mechanism behind process-induced distortions and stresses related to the Resin Transfer Moulding (RTM) manufacturing process. The aim is to comprehend the phenomena, to identify related parameters and to present compensation strategies.

Residual Stresses in Composite Materials

Residual Stresses in Composite Materials
Author: Mahmood M. Shokrieh
Publisher: Woodhead Publishing
Total Pages: 407
Release: 2014-02-14
Genre: Technology & Engineering
ISBN: 0857098594

Residual stresses are a common phenomenon in composite materials. They can either add to or significantly reduce material strength. Because of the increasing demand for high-strength, light-weight materials such as composites and their wide range of applications in the aerospace and automotive industries, in civil infrastructure and in sporting applications, it is critical that the residual stresses of composite materials are understood and measured correctly.The first part of this important book reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses. Various mathematical (analytical and numerical) methods for calculation of residual stresses in composite materials are also presented. Chapters in the first section of the book discuss the simulated hole drilling method, the slitting/crack compliance method, measuring residual stresses in homogeneous and composite glass materials using photoelastic techniques, and modeling residual stresses in composite materials. The second part of the book discusses residual stresses in polymer matrix, metal-matrix and a range of other types of composites. Moreover, the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses is discussed.Residual stresses in composite materials provides a comprehensive overview of this important topic, and is an invaluable reference text for both academics and professionals working in the mechanical engineering, civil engineering, aerospace, automotive, marine and sporting industries. - Reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses - Discusses residual stresses in polymer matrix, metal-matrix and other types of composite - Considers the addition of nanoparticles to the matrix of polymeric composites as a new technique for reduction of residual stresses

Residual Stress Measurement and the Slitting Method

Residual Stress Measurement and the Slitting Method
Author: Weili Cheng
Publisher: Springer Science & Business Media
Total Pages: 212
Release: 2007-02-24
Genre: Science
ISBN: 0387390308

This book provides complete coverage of the slitting method. It details new results in analysis, computation, and estimation and discusses different roles of residual stresses from the fracture mechanics perspective. It provides detailed formulations and examples of compliance functions, weighted least squares fit and convergence test in stress estimation, and computer programs to facilitate the implementation of the slitting method.

Introduction to Composite Materials Design, Second Edition

Introduction to Composite Materials Design, Second Edition
Author: Ever J. Barbero
Publisher: CRC Press
Total Pages: 564
Release: 2010-07-07
Genre: Technology & Engineering
ISBN: 1420079158

Presenting a wealth of completely revised examples and new information, Introduction to Composite Materials Design, Second Edition greatly improves on the bestselling first edition. It incorporates state-of-the-art advances in knowledge and design methods that have taken place over the last 10 years, yet maintains the distinguishing features and vital content of the original. New material in this second edition: Introduces new background topics, including design for reliability and fracture mechanics Revises and updates information on polymer matrices, modern fibers (e.g., carbon nanotubes, Basalt, Vectran) and fiber forms such as textiles/fabrics Includes new information on Vacuum Assisted Resin Transfer Molding (VARTM) Incorporates major advances in prediction of unidirectional-lamina properties Reworks sections on material failure, including the most advanced prediction and design methodologies, such as in situ strength and Mohr-Coulomb criterion, etc. Covers all aspects of preliminary design, relegating finite element analysis to a separate textbook Discusses methodology used to perform damage mechanics analysis of laminated composites accounting for the main damage modes: longitudinal tension, longitudinal compression, transverse tension, in-plane shear, and transverse compression Presents in-depth analysis of composites reinforced with plain, twill, and satin weaves, as well as with random fiber reinforcements Expands the analysis of thin walled beams with newly developed examples and MATLAB® code Addresses external strengthening of reinforced-concrete beams, columns, and structural members subjected to both axial and bending loads The author distributes 78 fully developed examples throughout the book to illustrate the application of presented analysis techniques and design methodology, making this textbook ideally suited for self-study. Requiring no more than senior undergraduate-level understanding of math and mechanics, it remains an invaluable tool for students in the engineering disciplines, as well as for self-studying, practicing engineers.

Modeling Methods for Process Induced Distortions of CFRP-Parts produced in the Prepreg-Autoclave-Process

Modeling Methods for Process Induced Distortions of CFRP-Parts produced in the Prepreg-Autoclave-Process
Author: Tim Frerich
Publisher: Logos Verlag Berlin GmbH
Total Pages: 190
Release: 2023-06-20
Genre: Technology & Engineering
ISBN: 3832556435

Process induced distortions are a challenge in the production of high-performance components made of carbon fiber reinforced plastics. In order to prevent the distortions, a prediction is of great utility. For components manufactured in the prepreg autoclave process, which is often used in the aerospace industry, prediction methods are investigated within this work. First, the state of the art is discussed and, based on this, two promising approaches are identified, which are further investigated and implemented: A rapid simulation approach and a complex one, which requires more effort but allows further investigations of the distortions. For the latter approach, new material models and rules of mixture are developed that take into account modern material architectures with interleaf layers. Using these material models, the observed material behavior can be represented more accurately than with material models from the literature. The results obtained by both approaches are compared with experimental results. A good agreement can be shown between the measurements and the simulation.

Analysis of Composite Structures

Analysis of Composite Structures
Author: Christian Decolon
Publisher: Elsevier
Total Pages: 351
Release: 2004-07-01
Genre: Technology & Engineering
ISBN: 0080527175

This book provides the basis for calculations of composite structures, using continuum mechanics to facilitate the treatment of more elaborate theories. A composite structure combines traditional materials (such as concrete) with new materials (such as high performance fibres) to explore and develop new structures.The author deals with individual layers in laminate composites, discussing the basic laws that govern mixtures.·Recommended for both student and professional use ·A systematic, compact presentation in a single volume·Covers the governing equations of composite beams, plates and structures

Residual Stresses in Composite Materials

Residual Stresses in Composite Materials
Author: Mahmood M. Shokrieh
Publisher: Woodhead Publishing
Total Pages: 506
Release: 2021-06-22
Genre: Technology & Engineering
ISBN: 0128188189

The residual stress is a common phenomenon in composite materials. They can either add to or significantly reduce material strength. Because of the increasing demand for high-strength, lightweight materials such as composites and their wide range of applications; it is critical that the residual stresses of composite materials are understood and measured correctly.The first edition of this book consists of thirteen chapters divided into two parts. The first part reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses. There are also additional chapters on using mathematical (analytical and numerical) methods for the calculation of residual stresses in composite materials. These include the simulated hole drilling method, the slitting/crack compliance method, measuring residual stresses in homogeneous and composite glass materials using photoelastic techniques, and modeling residual stresses in composite materials. The second part of the book discusses measuring residual stresses in different types of composites including polymer and metal matrix composites. The addition of nanoparticles to the matrix of polymeric composites as a new technique for the reduction of residual stresses is also discussed.In the Second Edition of this book, each of the original chapters of the first edition has been fully updated, taking into account the latest research and new developments. There are also five new chapters on the theoretical and experimental studies of residual stresses in the composite integrated circuits; residual stresses in additive manufacturing of polymers and polymer matrix composites; residual stresses in metal matrix composites fabricated by additive manufacturing; the eigenstrain based method for the incremental hole-drilling technique; and the estimation of residual stresses in polymer matrix composites using the digital image correlation technique.Residual Stresses in Composite Materials, Second Edition, provides a unique and comprehensive overview of this important topic and is an invaluable reference text for both academics and professionals working in the mechanical engineering, civil engineering, aerospace, automotive, marine, and sporting industries. - Presents the latest developments on theoretical and experimental studies of residual stresses in composites - Reviews destructive and non-destructive testing (NDT) techniques for measuring residual stresses - Discusses residual stresses in the polymer matrix, metal matrix, and ceramic matrix composites - Considers the addition of nanoparticles to the matrix as a new technique for reduction of residual stresses in polymeric composites - Introduces the latest advancements of research on the residual stresses in additive-manufactured polymer and metal matrix composites

The Virtual Crack Closure Technique: History, Approach and Applications

The Virtual Crack Closure Technique: History, Approach and Applications
Author: Ronald Krueger
Publisher:
Total Pages: 66
Release: 2002
Genre:
ISBN:

An overview of the virtual crack closure technique is presented. The approach used is discussed, the history summarized, and insight into its applications provided. Equations for two-dimensional quadrilateral elements with linear and quadratic shape functions are given. Formula for applying the technique in conjuction with three-dimensional solid elements as well as plate/shell elements are also provided. Necessary modifications for the use of the method with geometrically nonlinear finite element analysis and corrections required for elements at the crack tip with different lengths and widths are discussed. The problems associated with cracks or delaminations propagating between different materials are mentioned briefly, as well as a strategy to minimize these problems. Due to an increased interest in using a fracture mechanics based approach to assess the damage tolerance of composite structures in the design phase and during certification, the engineering problems selected as examples and given as references focus on the application of the technique to components made of composite materials.

Heat Transfer in Polymer Composite Materials

Heat Transfer in Polymer Composite Materials
Author: Nicolas Boyard
Publisher: John Wiley & Sons
Total Pages: 464
Release: 2016-03-28
Genre: Science
ISBN: 1848217617

This book addresses general information, good practices and examples about thermo-physical properties, thermo-kinetic and thermo-mechanical couplings, instrumentation in thermal science, thermal optimization and infrared radiation.

Residual Stresses 2018

Residual Stresses 2018
Author: Marc Seefeldt
Publisher: Materials Research Forum LLC
Total Pages: 310
Release: 2018-10-10
Genre: Technology & Engineering
ISBN: 1945291893

The European Conference on Residual Stresses (ECRS) series is the leading European forum for scientific exchange on internal and residual stresses in materials. It addresses both academic and industrial experts and covers a broad gamut of stress-related topics from instrumentation via experimental and modelling methodology up to stress problems in specific processes such as welding or shot-peening, and their impact on materials properties. Chapters: Diffraction Methods; Mechanical Relaxation Methods; Acoustic and Electromagnetic Methods; Composites, Nano and Microstructures; Films, Coatings and Oxides; Cold Working and Machining; Heat Treatments and Phase Transformations; Welding, Fatigue and Fracture: Stresses in Additive Manufacturing.