Download or read book Rate Dependent Stress Strain Behavior of Advanced Polymer Matrix Composites written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-10 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The formulation of an elastic/viscoplastic constitutive model which was used to predict the measured behavior of graphite/thermoplastic and graphite/bismaleimide composite materials at elevated temperature is described. The model incorporates the concepts of overstress and effective strain/strain to provide a simple formulation which was able to account for material behavior under monotonic tension or compression loads over a temperature range of 23 to 200 C. Observed behavior such as stress relaxation and steady state creep, in off-axis tension and compression tests, were predicted by the model. Material constants required by the model were extracted from simple off-axis test data. Gates, Thomas S. Langley Research Center RTOP 505-63-01-05...

Download or read book Rate Dependent Stress strain Behavior of Advanced Polymer Matrix Composites written by and published by . This book was released on 1991 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Matrix Dominated Stress strain Behavior in Polymeric Composites Effects of Hold Time Nonlinearity and Rate Dependency written by and published by . This book was released on 1992 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strain Rate Dependent Modeling of Polymer Matrix Composites written by Robert K. Goldberg and published by . This book was released on 1999 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Matrix Dominated Stress Strain Behavior in Polymeric Composites written by TS. Gates and published by . This book was released on 1993 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to help understand matrix-dominated behavior in laminated polymer matrix composites, an elastic/viscoplastic constitutive model was developed and used to predict stress/strain behavior of both off-axis and angle-ply symmetric laminates under in-plane, isothermal, axial tensile loading.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Strain Rate Deformation Modeling of a Polymer Matrix Composite written by and published by . This book was released on 1998 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Implementation of Laminate Theory Into Strain Rate Dependent Micromechanics Analysis of Polymer Matrix Composites written by Robert K. Goldberg and published by . This book was released on 2000 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Temperature and Environmental Effects on Polymeric Composites written by Charles E. Harris and published by ASTM International. This book was released on 1993 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerospace and naval applications of polymers in conditions once thought too harsh for them, take center stage in the survey of how polymer composites react to environmental conditions. A dozen papers from a symposium in San Diego, October 1991, describe damage mechanisms and failure, materials behavior under combined effects, and constitutive models, sometimes considering polymers as a whole, but more often specific groups or composites. No index. Annotation copyright by Book News, Inc., Portland, OR.

Download or read book Strain Rate Dependent Deformation and Strength Modeling of a Polymer Matrix Composite Utilizing a Micromechanics Approach written by Robert Keith Goldberg and published by . This book was released on 1999 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strain Rate Dependent Modeling of Polymer Matrix Composites written by Robert K. Goldberg and published by . This book was released on 1999 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Creep and Fatigue in Polymer Matrix Composites written by Rui Miranda Guedes and published by Woodhead Publishing. This book was released on 2019-03-14 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: Creep and Fatigue in Polymer Matrix Composites, Second Edition, updates the latest research in modeling and predicting creep and fatigue in polymer matrix composites. The first part of the book reviews the modeling of viscoelastic and viscoplastic behavior as a way of predicting performance and service life. Final sections discuss techniques for modeling creep rupture and failure and how to test and predict long-term creep and fatigue in polymer matrix composites. Reviews the latest research in modeling and predicting creep and fatigue in polymer matrix composites Puts a specific focus on viscoelastic and viscoplastic modeling Features the time-temperature-age superposition principle for predicting long-term response Examines the creep rupture and damage interaction, with a particular focus on time-dependent failure criteria for the lifetime prediction of polymer matrix composite structures that are illustrated using experimental cases

Download or read book Ls Dyna Implementation of Polymer Matrix Composite Model Under High Strain Rate Impact written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-20 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: A recently developed constitutive model is implemented into LS-DYNA as a user defined material model (UMAT) to characterize the nonlinear strain rate dependent behavior of polymers. By utilizing this model within a micromechanics technique based on a laminate analogy, an algorithm to analyze the strain rate dependent, nonlinear deformation of a fiber reinforced polymer matrix composite is then developed as a UMAT to simulate the response of these composites under high strain rate impact. The models are designed for shell elements in order to ensure computational efficiency. Experimental and numerical stress-strain curves are compared for two representative polymers and a representative polymer matrix composite, with the analytical model predicting the experimental response reasonably well. Zheng, Xia-Hua and Goldberg, Robert K. and Binienda, Wieslaw K. and Roberts, Gary D. Glenn Research Center NASA/TM-2003-212583, E-14123, NAS 1.15:212583

Download or read book Going to Extremes written by National Research Council and published by National Academies Press. This book was released on 2005-10-22 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced polymer matrix composites (PMC) have many advantages such as light weight and high specific strength that make them useful for many aerospace applications. Enormous uncertainty exists, however, in predicting long-term changes in properties of PMCs under extreme environmental conditions, which has limited their use. To help address this issue, the Department of Defense requested a study from the NRC to identify the barriers and limitations to the use of PMCs in extreme environments. The study was to focus on issues surrounding methodologies for predicting long-term performance. This report provides a review of the challenges facing application of PMCs in extreme environments, the current understanding of PMC properties and behavior, an analysis of the importance of data in developing effective models, and recommendations for improving long-term predictive methodologies.

Download or read book Computational Simulation of the High Strain Rate Tensile Response of Polymer Matrix Composites written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-19 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: A research program is underway to develop strain rate dependent deformation and failure models for the analysis of polymer matrix composites subject to high strain rate impact loads. Under these types of loading conditions, the material response can be highly strain rate dependent and nonlinear. State variable constitutive equations based on a viscoplasticity approach have been developed to model the deformation of the polymer matrix. The constitutive equations are then combined with a mechanics of materials based micromechanics model which utilizes fiber substructuring to predict the effective mechanical and thermal response of the composite. To verify the analytical model, tensile stress-strain curves are predicted for a representative composite over strain rates ranging from around 1 x 10(exp -5)/sec to approximately 400/sec. The analytical predictions compare favorably to experimentally obtained values both qualitatively and quantitatively. Effective elastic and thermal constants are predicted for another composite, and compared to finite element results. Goldberg, Robert K. Glenn Research Center NASA/TM-2002-211489, E-13257, NAS 1.15:211489

Download or read book Computational Simulation of the High Strain Rate Tensile Response of Polymer Matrix Composites written by and published by . This book was released on 2002 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Strain Rate Deformation Modeling of a Polymer Matrix Composite Part 1 Matrix Constitutive Equations written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-10-18 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently applications have exposed polymer matrix composite materials to very high strain rate loading conditions, requiring an ability to understand and predict the material behavior under these extreme conditions. In this first paper of a two part report, background information is presented, along with the constitutive equations which will be used to model the rate dependent nonlinear deformation response of the polymer matrix. Strain rate dependent inelastic constitutive models which were originally developed to model the viscoplastic deformation of metals have been adapted to model the nonlinear viscoelastic deformation of polymers. The modified equations were correlated by analyzing the tensile/ compressive response of both 977-2 toughened epoxy matrix and PEEK thermoplastic matrix over a variety of strain rates. For the cases examined, the modified constitutive equations appear to do an adequate job of modeling the polymer deformation response. A second follow-up paper will describe the implementation of the polymer deformation model into a composite micromechanical model, to allow for the modeling of the nonlinear, rate dependent deformation response of polymer matrix composites. Goldberg, Robert K. and Stouffer, Donald C. Glenn Research Center RTOP 523-24-13...