Author: A. R. ShahPublisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 16
Book Description
Cyclic Load Effects on Long Term Behavior of Polymer Matrix Composites
Author: A. R. ShahPublisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 16
Book Description
Effect of Cyclic Thermo-Mechanical Loads on Fatigue Reliability in Polymer Matrix Composites
Author: A. R. ShahPublisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 20
Book Description
Probabilistic Simulation of Long Term Behavior in Polymer Matrix Composites
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722602734
Category :
Languages : en
Pages : 24
Book Description
A methodology to compute cumulative probability distribution functions (CDF) of fatigue life for different ratios, r of applied stress to the laminate strength based on first ply failure criteria has been developed and demonstrated. Degradation effects due to long term environmental exposure and mechanical cyclic loads are considered in the simulation process. A unified time-stress dependent multi-factor interaction equation model developed at NASA Lewis Research Center has been used to account for the degradation/aging of material properties due to cyclic loads. Fast probability integration method is used to perform probabilistic simulation of uncertainties. Sensitivity of fatigue life reliability to uncertainties in the primitive random variables are computed and their significance in the reliability based design for maximum life is discussed. The results show that the graphite/epoxy (0/+45/90) deg laminate with ply thickness 0.125 in. has 500,000 cycles life for applied stress to laminate strength ratio of 0.6 and a reliability of 0.999. Also, the fatigue life reliability has been found to be most sensitive to the ply thickness and matrix tensile strength. Tighter quality controls must therefore be enforced on ply thickness and matrix strength in order to achieve high reliability of the structure. Shah, A. R. and Singhal, S. N. and Murthy, P. L. N. and Chamis, C. C. Glenn Research Center NAS3-27186; RTOP 505-62-10...
Probabilistic Simulation of Long Term Behavior in Polymer Matrix Composites
Author: Long-Term Durability of Polymeric Matrix Composites
Author: Kishore V. PochirajuPublisher: Springer Science & Business Media
ISBN: 1441993088
Category : Technology & Engineering
Languages : en
Pages : 681
Book Description
Long-Term Durability of Polymeric Matrix Composites presents a comprehensive knowledge-set of matrix, fiber and interphase behavior under long-term aging conditions, theoretical modeling and experimental methods. This book covers long-term constituent behavior, predictive methodologies, experimental validation and design practice. Readers will also find a discussion of various applications, including aging air craft structures, aging civil infrastructure, in addition to engines and high temperature applications.
Going to Extremes
Author: National Research CouncilPublisher: National Academies Press
ISBN: 0309097150
Category : Technology & Engineering
Languages : en
Pages : 80
Book Description
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.
Creep and Fatigue in Polymer Matrix Composites
Author: Rui Miranda GuedesPublisher: Woodhead Publishing
ISBN: 0081026021
Category : Technology & Engineering
Languages : en
Pages : 586
Book Description
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
Matrix Dominated Stress/strain Behavior in Polymeric Composites: Effects of Hold Time, Nonlinearity and Rate Dependency
Author: Long Term Durability of Structural Materials
Author: P.J.M. MonteiroPublisher: Elsevier
ISBN: 0080535593
Category : Technology & Engineering
Languages : en
Pages : 313
Book Description
"Long Term Durability of Structural Materials" features proceedings of the workshop held at Berkeley, CA in October, 2000. It brought together engineers and scientists, who have received grants from the initiative NSF 98-42, to share their results on the study of long-term durability of materials and structures. The major objective was to develop new methods for accelerated short-term laboratory or in-situ tests which allow accurate, reliable, predictions of the long-term performance of materials, machines and structures. To achieve this goal it was important to understand the fundamental nature of the deterioration and damage processes in materials and to develop innovative ways to model the behavior of these processes as they affect the life and long-term performance of components, machines and structures. The researchers discussed their approach to include size effects in scaling up from laboratory specimens to actual structures. Accelerated testing and durability modeling techniques developed were validated by comparing their results with performance under actual operating conditions. The main mechanism of the deterioration discussed included environmental effects and/or exposure to loads, speeds and other operating conditions that are not fully anticipated in the original design. A broad range of deterioration damage, such as fatigue, overload, ultraviolet damage, corrosion, and wear was presented. A broad range of materials of interest was also discussed, including the full spectrum of construction materials, metals, ceramics, polymers, composites, and coatings. Emphasis was placed on scale-dependence and history of fabrication on resulting mechanical behavior of materials.
Fatigue of Composite Materials
Author: K.L. ReifsniderPublisher: Elsevier
ISBN: 0444597182
Category : Technology & Engineering
Languages : en
Pages : 532
Book Description
This book provides the first comprehensive review of its kind on the long-term behaviour of composite materials and structures subjected to time variable mechanical, thermal, and chemical influences, a subject of critical importance to the design, development, and certification of high performance engineering structures. Specific topics examined include damage, damage characterization, and damage mechanics; fatigue testing and evaluation; fatigue behaviour of short and long fibre reinforced polymer and metal matrix materials; viscoelastic and moisture effects; delamination; statistical considerations; the modeling of cumulative damage development; and life prediction. The volume provides an extensive presentation of data, discussions, and comparisons on the behaviour of the major types of material systems in current use, as well as extensive analysis and modeling (including the first presentation of work not found elsewhere). The book will be of special interest to engineers concerned with reliability, maintainability, safety, certification, and damage tolerance; to materials developers concerned with making materials for long-term service, especially under severe loads and environments, and to lecturers, students, and researchers involved in material system design, performance, solid mechanics, fatigue, durability, and composite materials. The scope of the work extends from entry level material to the frontiers of the subject.