STP 1357 Time Dependent and Nonlinear Effects in Polymers and Composites Richard A. Schapery and C. T. Sun, editors ASTM Stock Number: STP 1357 ASTM 100 Barr Harbor Drive West Conshohocken, PA 19428-2959 Printed in the U.S.A.
Library of Congress Cataloging-in-Publication Data Schapery, Richard Allan. Time dependent and nonlinear effects in polymers and composites / Richard A. Schapery and C. T. Sun, editors. p. cm. -- (STP ; 1357) "ASTM Stock Number: STP1357." Includes bibliographical references and index. ISBN 0-8031-2601-8 1. Polymers--Mechanical properties. 2. Composite materials--mechanical properties. Nonlinear mechanics. I. Sun, C. T. (Chang Tsan), 1928- I1. Title. III. ASTM special technical publication ; 1357. 3. TA455.P58 $34 2000 620.1'9204292--dc21 99-056137 Copyright 9 2000 AMERICAN SOCIETY FOR TESTING AND MATERIALS, West Conshohocken, PA. All rights reserved. This material may not be reproduced or copied, in whole or in part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of the publisher. Photocopy Rights Authorization to photocopy items for internal, personal, or educational classroom use, or the internal, personal, or educational classroom use of specific clients, is granted by the American Society for Testing and Materials (ASTM) provided that the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: 508-750-8400; online: http://www.copyright.com/. Peer Review Policy Each paper published in this volume was evaluated by two peer reviewers and at least one editor. The authors addressed all of the reviewers' comments to the satisfaction of both the technical editor(s) and the ASTM Committee on Publications. The quality of the papers in this publication reflects not only the obvious efforts of the authors and the technical editor(s), but also the work of the peer reviewers. In keeping with long standing publication practices, ASTM maintains the anonymity of the peer reviewers. The ASTM Committee on Publications acknowledges with appreciation their dedication and contribution of time and effort on behalf of ASTM. Printed in Philadelphia, PA January 2000
Foreword The Symposium on Time Dependent and Nonlinear Effects in Polymers and Composites was held on May 4-5, 1998 in Atlanta, Georgia. ASTM Committee D-30 on Composite Materials sponsored the Symposium. Richard Schapery, the University of Texas at Austin, and C. T. Sun, Purdue University, presided as symposium co-chairmen and are editors of this publication.
Contents Overview vii POLYMERS Mechanical Properties of Degraded PMR-15 Resin--L. c. TSUJI, H. L. McMANUS, AND K. J. BOWLES Time Dependent Volume and Enthalpy Responses in Polymers-- G. B. McKENNA AND S. L. SIMON Creep Behavior in Amorphous and Semicrystalline PEN~M. L. CERRADA AND G. B. McKENNA A Constitutive Model for Long-Term Behavior of Polymers--i. D. SKRYPNYK, J. L. SPOORMAKER, AND P. KANDACHAR Implementation of Constitutive Model in FEA for Nonlinear Behavior of Plastics--i. D. SKRYPNYK, J. L. SPOORMAKER, AND W. SMIT The Effect of Nonlinear Viscoelasticity on Interfacial Shear Strength Measurements--G. A. HOLMES, R. C. PETERSON, D. L. HUNSTON, W. G. McDONOUGH, AND C. L. SCHUTTE An Overstress Model for Solid Polymer Deformation Behavior Applied to Nylon 66mE. KR~MPL AND KWANGSOO HO 18 47 70 83 98 118 COMPOSITES Aging During Elevated Temperature Stress Relaxation of IM7/K3B Composite--T. s. GATES, L. C. BRINSON, K. S. WHITLEY, AND T. BA1 Tensile and Compressive Creep of a Thermoplastic Polymer and the Effects of Physical Aging on the Composite Time-Dependent BehaviormD. R. VEAZIE ANY) T. S. GATES 141 160
Nonlinear Multiaxial Behavior and Failure of Fiber-Reinforced Composites-- S.-C. HUNG AND K. M. LIECHTI 176 Nonlinear and Dynamic Compressive Behavior of Composites with Fiber Waviness--H. M. HSIAO AND I. M. DANIEL 223 Nonlinear Viscoelastic Behavior of Rubber-Toughened Carbon and Glass/ Epoxy Composites--R. T. BOCCHIERI AND R. A. SCHAPERY A Viscoplasticity Model for Characterizing Loading and Unloading Behavior of Polymeric Composites--c. M. zhu AND C. T. SUN 238 266 Durability and Damage Tolerance of a Polyimide Chopped Fiber Composite Subjected to Thermomechanical Fatigue Missions and Creep Loadings-- M. G. CASTELLt, J. K. SUTTER, AND D. BENSON 285 Life Prediction of PPS Composites Subjected to Cyclic Loading at Elevated Temperatures--J s. LOVERICH, B. E. RUSSELL, S. W. CASE, AND K. L. RE1FSNIDER 310 Accelerated Strength Testing of Thermoplastic Composites--L R. REEDER, D. H. ALLEN, AND W. L. BRADLEY 318 Hygrothermal Modeling of Polymers and Polymer Matrix Composites-- SAMIT ROY 338 Hygrothermal Effects on Failure Mechanisms of Composite/Steel Bonded Joints--A. ROY, E. GONTCHAROVA-BENARD, J.-L. GACOUGNOLLE, AND P. DAVIES 353 Indexes 373
Overview Polymeric composites exhibit appreciable time-dependent and nonlinear mechanical behavior in many structural applications. Improved fundamental understanding of and predictive models for this behavior over service lifetimes in realistic environments are needed for composites to gain wider acceptance and to achieve a significantly increased level of structural efficiency and reliability in commercial and military applications. In advanced fibrous composites, the fiber phase is basically linearly elastic and shows little nonlinear and time-dependent behavior, if any. Thus, the nonelastic properties originate primarily from the matrix phase, including the polymer-fiber interphase zone. It is evident that to understand and to model the nonelastic behavior of composites, one must understand and be able to model this behavior in polymers. Understanding the in situ behavior of the polymeric matrix and its interaction with fibers is an important part of developing improved predictive models. Because there is now a considerable amount of research activity worldwide on time-dependent and nonlinear effects in polymers and composites, it is desirable to describe and assess recent developments and their practical significance as well as to identify important unsolved fundamental problems. For these reasons, the two related disciplines, polymers and composites, were brought together at the Symposium on Time-dependent and Nonlinear Effects in Polymers and Composites. One of the main objectives of this symposium was to join the effort of specialists in these two disciplines to advance research in this important area of polymeric composites. This volume contains eighteen papers presented at the Symposium. They are grouped under two subheadings, Polymers and ComposiWs. Under Polymers, the primary topics are chemical and physical aging, nonlinear viscoelasticity and viscoplasticity. A number of topics are addressed by the papers under Composites, including the effect of physical aging on time-dependent behavior of composites, multiaxial nonlinear effects, compressive behavior, nonlinear viscoelasticity and viscoplasticity, failure and failure mechanisms, hygrothermal effects, durability, and accelerated strength testing. We want to express our sincere thanks to all those who made the symposium and this STP possible. The excellent contributions of the authors, reviewers, presenters, session chairs, ASTM staff, and sponsoring technical committee are deeply appreciated. Richard A. Schapery The University of Texas, Austin, Texas; symposium cochairman and editor C. T. Sun Purdue University, West Lafayette, Indiana; symposium cochairman and coeditor vii
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