Download or read book A Model for the Viscoelastic and Viscoplastic Responses of Semicrystalline Polymers written by Jesper DeClaville Christiansen and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Viscoelastic and Viscoplastic Materials written by Mohamed El-Amin and published by BoD – Books on Demand. This book was released on 2016-09-21 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces numerous selected advanced topics in viscoelastic and viscoplastic materials. The book effectively blends theoretical, numerical, modeling and experimental aspects of viscoelastic and viscoplastic materials that are usually encountered in many research areas such as chemical, mechanical and petroleum engineering. The book consists of 14 chapters that can serve as an important reference for researchers and engineers working in the field of viscoelastic and viscoplastic materials.
Download or read book A COUPLED VISCOPLASTIC DAMAGE CONSTITUTIVE MODEL FOR SEMICRYSTALLINE POLYMERS written by and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : The ease of processing, recyclability, and ideal cost to weight ratio makes the semi-crystalline polymers attractive in the aerospace, automotive, and defense industries. Use of semicrystalline polymers for engineering design requires a thorough understanding of their response to mechanical deformation, rate of loading, temperature, and failure mechanisms. However, there lacks a generally agreed upon constitutive model to capture the large deformation elastic-viscoplastic response of semicrystalline polymers while incorporating the strain-rate dependence and damage behavior. To address this aspect, the objective of this dissertation is to develop an elastic-viscoplastic constitutive model to predict the rate dependent, large deformation response of semicrystalline polymers under tension and compression. In addition, a continuum scale damage model coupled with viscoplasticity is adopted to incorporate cavitation induced damage growth, coalescence, and fibrillation in the material. To validate the proposed model, uniaxial compression and tension experiments are conducted on isotactic polypropylene homopolymer within strain rates of 10-3 s-1 to 10-1 s-1. The constitutive model is implemented in a finite element program ABAQUS/Explicit (ABAQUS 2017) by writing a user material subroutine (VUMAT). With the model parameters properly calibrated, the present study shows that the proposed constitutive model is able to predict the macroscopic rate dependent load-displacement curves, as well as the fracture responses for various standard geometries.
Download or read book Polymer Viscoelasticity written by Evaristo Riande and published by CRC Press. This book was released on 1999-11-05 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt: Showcasing vital engineering applications to transient and dynamic pertubations of macromolecular materials, structural recovery's role in mechanical responses in the glassy state, and viscoelastic parameters that condition the non-Newtonian behaviour of polymers, this work presents a systematic account of the responses of macromolecular materials to mechanical force fields. It focuses on the most important features of the linear stress-strain relationships for ideal solids and liquids.
Download or read book Polymer Viscoelasticity written by Y.-H. Lin and published by World Scientific. This book was released on 2011 with total page 441 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers in great detail the Rouse-segment-based molecular theories in polymer viscoelasticity ? the Rouse theory and the extended reptation theory (based on the framework of the Doi?Edwards theory) ? that have been shown to explain experimental results in a consistently quantitative way. The explanation for the 3.4 power law of viscosity, quantitative line-shape analyses of viscoelastic responses and agreements between different sorts of viscoelastic responses, the consistency between the viscoelasticity and diffusion results, the clarification of the onset of entangelement, the discovery of the number of entanglement strands per cubed entanglement distance being a universal constant and the basic mechanism of the glass transition-related thermorheological complexity are discussed or shown in great detail. The mystery behind the success of the Rouse-segment-based molecular theories over the entropic region of a viscoelastic response is revealed by the Monte Carlo simulations on the Fraenkel chains. Specifically, the simulation studies give a natural explanation for the coexistence of the energy-driven and entropy-driven modes in a viscoelastic response and provide a theoretical basis resolving the paradox that the experimentally determined sizes of Rouse and Kuhn segments are nearly the same. This book starts from a very fundamental level; each chapter is built upon the contents of the previous chapters. Thus, the readers may use the book as a textbook and eventually reach an advanced research level. This book is also a useful source of reference for physicists, chemists and material scientists.
Download or read book Introduction to Polymer Viscoelasticity written by Montgomery T. Shaw and published by John Wiley & Sons. This book was released on 2005-08-19 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: A revised molecular approach to a classic on viscoelasticbehavior Because viscoelasticity affects the properties, appearance,processing, and performance of polymers such as rubber, plastic,and adhesives, a proper utilization of such polymers requires aclear understanding of viscoelastic behavior. Now in its third edition, Introduction to Polymer Viscoelasticityremains a classic in the literature of molecular viscoelasticity,bridging the gap between primers on polymer science and advancedresearch-level monographs. Assuming a molecular, rather than amechanical approach, the text provides a strong grounding in thefundamental concepts, detailed derivations, and particularattention to assumptions, simplifications, and limitations. This Third Edition has been entirely revised and updated to reflectrecent developments in the field. New chapters include: * Phenomenological Treatment of Viscoelasticity * Viscoelastic Models * Time-Temperature Correspondence * Transitions and Relaxation in Polymers * Elasticity of Rubbery Networks * Dielectric and NMR Methods With detailed explanations, corresponding equations, andexperimental methods, supported by real-life applications (as wellas the inclusion of a CD-ROM with data to support the exercises),this Third Edition provides today's students and professionals withthe tools they need to create polymers with more desirablequalities than ever.
Download or read book Viscoelastic Structures written by Aleksey D. Drozdov and published by Academic Press. This book was released on 1998-02-09 with total page 615 pages. Available in PDF, EPUB and Kindle. Book excerpt: Viscoelastic Structures covers the four basic problems in the mechanics of viscoelastic solids and structural members: construction of constitutive models for the description of thermoviscoelastic behavior of polymers; mathematical modeling of manufacturing advanced composite materials; optimal-design of structural members and technological processes of their fabrication; and stability analysis for thin-walled structural members driven by time-varying loads.This book familiarizes the reader with state-of-the-art mathematical models for advanced materials and processes, and demonstrates their applications in modeling and simulating specific manufacturing processes. Viscoelastic Structures also demonstrates the effects of material, geometrical, and technological parameters on the characteristic features of viscoelastic structures.1Presents state-of-the-art mathematical models and methods which serve for the analysis of advanced technological processes1Includes numerous examples to demonstrate theory which have not been included in previous literature1Employs one consistent, user-friendly method to study a number of technological processes1Features unique approach to aging materials1Appendices cover background material on tensor calculus, kinematics with finite strains, stochastic differential equations, and evolutionary equations with operator coefficients
Download or read book Engineering Optimization 2014 written by Hélder Rodrigues and published by CRC Press. This book was released on 2014-09-26 with total page 1080 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern engineering processes and tasks are highly complex, multi- and interdisciplinary, requiring the cooperative effort of different specialists from engineering, mathematics, computer science and even social sciences. Optimization methodologies are fundamental instruments to tackle this complexity, giving the possibility to unite synergistically team members’ inputs and thus decisively contribute to solving new engineering technological challenges. With this context in mind, the main goal of Engineering Optimization 2014 is to unite engineers, applied mathematicians, computer and other applied scientists working on research, development and practical application of optimization methods applied to all engineering disciplines, in a common scientific forum to present, analyze and discuss the latest developments in this area. Engineering Optimization 2014 contains the edited papers presented at the 4th International Conference on Engineering Optimization (ENGOPT2014, Lisbon, Portugal, 8-11 September 2014). ENGOPT2014 is the fourth edition of the biennial “International Conference on Engineering Optimization”. The first conference took place in 2008 in Rio de Janeiro, the second in Lisbon in 2010 and the third in Rio de Janeiro in 2012. The contributing papers are organized around the following major themes: - Numerical Optimization Techniques - Design Optimization and Inverse Problems - Effi cient Analysis and Reanalysis Techniques - Sensitivity Analysis - Industrial Applications - Topology Optimization For Structural Static and Dynamic Failures - Optimization in Oil and Gas Industries - New Advances in Derivative-Free Optimization Methods for Engineering Optimization - Optimization Methods in Biomechanics and Biomedical Engineering - Optimization of Laminated Composite Materials - Inverse Problems in Engineering Engineering Optimization 2014 will be of great interest to engineers and academics in engineering, mathematics and computer science.
Download or read book Viscoelasticity and Rheology written by Arthur S. Lodge and published by Academic Press. This book was released on 2014-06-28 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Viscoelasticity and Rheology covers the proceedings of a symposium by the same title, conducted by the Mathematics Research Center held at the University of Wisconsin-Madison on October 16-18, 1984. The contributions to the symposium are divided into four broad categories, namely, experimental results, constitutive theories, mathematical analysis, and computation. This 16-chapter work begins with experimental topics, including the motion of bubbles in viscoelastic fluids, wave propagation in viscoelastic solids, flows through contractions, and cold-drawing of polymers. The next chapters covering constitutive theories explore the molecular theories for polymer solutions and melts based on statistical mechanics, the use and limitations of approximate constitutive theories, a comparison of constitutive laws based on various molecular theories, network theories and some of their advantages in relation to experiments, and models for viscoplasticity. These topics are followed by discussions of the existence, regularity, and development of singularities, change of type, interface problems in viscoelasticity, existence for initial value problems and steady flows, and propagation and development of singularities. The remaining chapters deal with the numerical simulation of flow between eccentric cylinders, flow around spheres and bubbles, the hole pressure problem, and a review of computational problems related to various constitutive laws. This book will prove useful to chemical engineers, researchers, and students.
Download or read book Journal of Rheology written by and published by . This book was released on 2003 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear Macromechanical Analysis of Polymeric Materials written by Hossein Sepiani and published by . This book was released on 2017 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new methodology for predicting the short term and long term responses of viscoelastic and viscoplastic materials is developed in this research. The methodology aims to predict the behaviour of viscoelastic/viscoplastic isotropic material subjected to loading in isochronous condition (temperature effects are not included). The methodology is implemented in a finite element (FE) procedure through a user defined material subroutine (UMAT) which is linked to ABAQUS software and is called at each increment and material calculation point. The built-in viscoelastic ABAQUS procedure is not able to analyze the nonlinear behaviour of viscoelastic and viscoplastic materials, hence, a specific procedure needs to be defined, which justifies the application of user generated subroutines for material definition in this work. The development of the methodology consists of four major parts: 1) development of material models for Nonlinear Viscoelastic (NVE) and Nonlinear Viscoplastic (NVP) materials; 2) development of macromechanical NVE and NVP models; 3) development of failure model; 4) implementation in finite element procedure. For the first part, a new approach is developed for macromechanical constitutive formulations for time-dependent materials. In particular, two phenomenological constitutive models for polymer materials are illustrated, describing time-dependent and nonlinear mechanical behaviour, the Nonlinear Viscoelastic (NVE) and Nonlinear Viscoplastic (NVP) material models. In the proposed approach, short term creep test data are used for modelling both short term and long term responses. A major part of the experiments were done by Liu (Liu, 2007), while the rest have been provided by ExxonMobil, a division of Imperial Oil. The differential form of the model is used to simulate typical Nonlinear Viscoelastic polymeric behaviour using a combination of springs and dashpots. Unified plasticity theory is then used to develop the second model, the Nonlinear Viscoplastic one. Least squares fitting is applied for the determination of material parameters for both models based on experimental results. Due to practical constraints, experimental data are usually available for short term time-frames only. In the presented proposed formulation, the material parameters determined from short term testing are used to obtain material parameter relationships for predicting the long term material response. This is done by extending short term information for longer time frames. The second part, which is the development of macromechanical NVE and NVP models, is done using two theories: multiple integral and single integral representations of constitutive equations. Multiple integral representation for three-dimensional behaviour is an extension of linear superposition to the nonlinear range. The method is based on the small strain assumption, but is extended to large deformation for materials in which the stress-strain relation is nonlinear and the concept of incompressibility is governing. Similar to the material modelling (first part), the modelling process uses springs and dash-pots, and a power-law approximation function method for viscoelastic and viscoplastic nonlinear behaviour, respectively. Single integral representation, on the other hand, is a simplified form of multiple integral representation. Based on Schapery's single integral constitutive law, a solution procedure has been provided to solve nonlinear viscoelastic behaviour. This procedure is applicable to three dimensional problems and uses time- and stress-dependent material properties to characterize the nonlinear behaviour of the material. The approximation equations describing material behaviour are defined based on the material response in a short test time frame. For this estimation, Prony series method is used the basis of the constitutive relations is the non-separable form of the equations. For the failure modelling (third part), an energy based method of delayed failure is presented. The delayed failure approach is applicable to both NVE and NVP modelling for both multiple integral and single integral theories. The approach works with limiting the strain energy of the material to a boundary which is the resilience limit. Here, based on Schapery's single integral constitutive law, the delayed failure criterion is employed for NVE modelling, which helps to solve for the polymer's time to failure involving material nonlinearity. In the last part, the proposed viscoelastic and viscoplastic models, as well as the delayed failure criterion, are implemented in a user material algorithm of the FE general purpose program ABAQUS and the validity of the models is assessed by comparisons with experimental observations from tests on polyethylene material samples in one-dimensional tensile loading (these tests are done by others). The experiments are short term loading, long term loading, and step loading. Comparisons show that the proposed constitutive model can satisfactorily represent the time-dependent mechanical behaviour of polymers even for long term predictions and the developed formulation provides a flexible and reliable framework for predicting load responses of polymers. It is also concluded that with proper material properties to reflect the deformation involved in the mechanical tests, the deformation behaviour observed experimentally can be accurately predicted using the Finite Element Method (FEM) simulation.
Download or read book Proceedings of the 4th International Conference on Numerical Modelling in Engineering written by Magd Abdel Wahab and published by Springer Nature. This book was released on 2022-03-28 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers outstanding papers on numerical modeling in Mechanical Engineering (Volume 2) as part of the 2-volume proceedings of the 4th International Conference on Numerical Modeling in Engineering (NME 2021), which was held in Ghent, Belgium, on 24-25 August 2021. The overall objective of the conference was to bring together international scientists and engineers in academia and industry from fields related to advanced numerical techniques, such as the finite element method (FEM), boundary element method (BEM), isogeometric analysis (IGA), etc., and their applications to a wide range of engineering disciplines. This book addresses numerical simulations of various mechanical and materials engineering industrial applications such as aerospace applications, acoustic analysis, bio-mechanical applications, contact problems and wear, heat transfer analysis, vibration and dynamics, transient analysis, nonlinear analysis, composite materials, polymers, metal alloys, fracture mechanics, fatigue of materials, creep, mechanical behavior, micro-structure, phase transformation, and crystal plasticity.
Download or read book Introduction to Polymer Viscoelasticity written by John J. Aklonis and published by . This book was released on 1983 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: A molecular approach to the fundamentals of viscoelastic behavior in polymers, bridging the gap between introductory accounts and advanced research level monographs. This second edition includes new coverage of the theory of reptation, the kinetic theory of rubber elasticity, and an entirely new chapter on dielectric relaxation. Presents all derivations in detail, and treats concepts and models paying special attention to assumptions, simplifications and limitations. Provides problems at the end of each chapter.
Download or read book Handbook of Properties of Textile and Technical Fibres written by A. R. Bunsell and published by Woodhead Publishing. This book was released on 2018-01-02 with total page 1054 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Properties of Textile and Technical Fibres, Second Edition introduces tensile properties and failure and testing of fibers, also examining tensile properties and the failure of natural fibers, such as cotton, hemp, flax, agave, wool and silk. Next, the book discusses the tensile properties and failure of synthetic fibers, ranging from polyamide, polyester, polyethylene and carbon fibers. Chapters provide a general background of the fiber, including its manufacture, microstructure, factors that affect tensile properties and methods to improve tensile failure. With its distinguished editor and international contributors, this book is an important reference for fiber scientists, textile technologists, engineers and academics. - Offers up-to-date coverage of new and advanced materials for the fiber and textile industries - Reviews structure-property relationships of high-performance natural, synthetic polymer and inorganic fibers - Offers a range of perspectives on the tensile properties of fibers from an international team of authors with diverse expertise in academic research and in textile development and manufacture
Download or read book Dynamic Substructures Volume 4 written by Andreas Linderholt and published by Springer. This book was released on 2019-06-14 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamics of Coupled Structures, Volume 4: Proceedings of the 37th IMAC, A Conference and Exposition on Structural Dynamics, 2019, the fourth volume of eight from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of the Dynamics of Coupled Structures, including papers on: Methods for Dynamic Substructures Applications for Dynamic Substructures Interfaces & Substructuring Frequency Based Substructuring Transfer Path Analysis
Download or read book Viscoelastic Properties of Polymers written by John D. Ferry and published by John Wiley & Sons. This book was released on 1980-09-16 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Viscoelastic behavior reflects the combined viscous and elastic responses, under mechanical stress, of materials which are intermediate between liquids and solids in character. Polymers the basic materials of the rubber and plastic industries and important to the textile, petroleum, automobile, paper, and pharmaceutical industries as well exhibit viscoelasticity to a pronounced degree. Their viscoelastic properties determine the mechanical performance of the final products of these industries, and also the success of processing methods at intermediate stages of production. Viscoelastic Properties of Polymers examines, in detail, the effects of the many variables on which the basic viscoelastic properties depend. These include temperature, pressure, and time; polymer chemical composition, molecular weight and weight distribution, branching and crystallinity; dilution with solvents or plasticizers; and mixture with other materials to form composite systems. With guidance by molecular theory, the dependence of viscoelastic properties on these variables can be simplified by introducing certain ancillary concepts such as the fractional free volume, the monomeric friction coefficient, and the spacing between entanglement loci, to provide a qualitative understanding and in many cases a quantitative prediction of how to achieve desired results. The phenomenological theory of viscoelasticity which permits interrelation of the results of different types of experiments is presented first, with many useful approximation procedures for calculations given. A wide variety of experimental methods is then described, with critical evaluation of their applicability to polymeric materials of different consistencies and in different regions of the time scale (or, for oscillating deformations, the frequency scale). A review of the present state of molecular theory follows, so that viscoelasticity can be related to the motions of flexible polymer molecules and their entanglements and network junctions. The dependence of viscoestic properties on temperature and pressure, and its descriptions using reduced variables, are discussed in detail. Several chapters are then devoted to the dependence of viscoelastic properties on chemical composition, molecular weight, presence of diluents, and other features, for several characteristic classes of polymer materials. Finally, a few examples are given to illustrate the many potential applications of these principles to practical problems in the processing and use of rubbers, plastics, and fibers, and in the control of vibration and noise. The third edition has been brought up to date to reflect the important developments, in a decade of exceptionally active research, which have led to a wider use of polymers, and a wider recognition of the importance and range of application of viscoelastic properties. Additional data have been incorporated, and the book s chapters on dilute solutions, theory of undiluted polymers, plateau and terminal zones, cross-linked polymers, and concentrated solutions have been extensively rewritten to take into account new theories and new experimental results. Technical managers and research workers in the wide range of industries in which polymers play an important role will find that the book provides basic information for practical applications, and graduate students in chemistry and engineering will find, in its illustrations with real data and real numbers, an accessible introduction to the principles of viscoelasticity.
Download or read book Viscoelasticity of Polymers written by Kwang Soo Cho and published by Springer. This book was released on 2016-05-30 with total page 615 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a comprehensive introduction to polymer rheology with a focus on the viscoelastic characterization of polymeric materials. It contains various numerical algorithms for the processing of viscoelastic data, from basic principles to advanced examples which are hard to find in the existing literature. The book takes a multidisciplinary approach to the study of the viscoelasticity of polymers, and is self-contained, including the essential mathematics, continuum mechanics, polymer science and statistical mechanics needed to understand the theories of polymer viscoelasticity. It covers recent achievements in polymer rheology, such as theoretical and experimental aspects of large amplitude oscillatory shear (LAOS), and numerical methods for linear viscoelasticity, as well as new insights into the interpretation of experimental data. Although the book is balanced between the theoretical and experimental aspects of polymer rheology, the author’s particular interest in the theoretical side will not remain hidden. Aimed at readers familiar with the mathematics and physics of engineering at an undergraduate level, the multidisciplinary approach employed enables researchers with various scientific backgrounds to expand their knowledge of polymer rheology in a systematic way.
