Download or read book Effect of Ply Constraint on Fatigue Damage Development in Composite Material Laminates written by WW. Stinchcomb and published by . This book was released on 1981 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laminae of composite materials are bonded together to form a laminate for the purpose of achieving strength and stiffness in certain desired directions. Although a direct use of laminae strength and stiffness properties can be used to determine the properties of an undamaged laminate, it is well known that the manner in which local damage initiates, grows, and combines is not the same in an unconstrained lamina as it is when the same lamina is constrained by other laminae in a laminate. This paper addresses the question of constraint effects directly and discusses the consequences of such effects on the development of fatigue damage in graphite epoxy laminates. Results of monotonic tension tests, tension-tension fatigue tests, and nondestructive investigations are reported for several constraint situations and are compared with the results of several analyses.
Download or read book Fatigue Damage strength Relationships in Composite Laminates Volume 1 written by Kenneth L. Reifsnider and published by . This book was released on 1983 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report is Vol. I of a 2-part final report on the activities which were conducted under Contract No. F33615-81-3225. The general objective of this program was to investigate the precise nature of the damage events caused by cyclic (fatigue) loading of composite laminates that are directly related to fracture of those laminates, to develop a conceptual understanding of how those damage events reduce the residual strength of the laminates, and to determine how the collective damage condition following long-term cyclic loading precipitates the final fracture event. The program was conducted in four phases: (1) the development of fatigue damage during long-term cyclic loading was investigated in such a way that the damage events which occur quite late in the fatigue life of the material, just prior to fracture, were identified and characterized; (2) the special contribution and nature of fiber fracture was investigated; (3) the nature of the collective damage condition which precipitates the fracture event under long-term fatigue loading was investigated; (4) a philosophy of fracture in composite laminates following severe damage development due to cyclic loading was developed. A wide variety of destructive and nondestructive experimental evaluation schemes were used in the program, and several analytical efforts were conducted to support the experimental activities.
Download or read book Fatigue of Fibrous Composite Materials written by K. N. Lauraitis and published by ASTM International. This book was released on 1981 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Damage Strength Relationships in Composite Laminates Volume 2 written by Kenneth L. Reifsnider and published by . This book was released on 1984 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents information and experience generated during the subject investigation which provided support for the major thrust of the effort, but was not the eventual focus of the program. The activities are discussed in the context of the various experimental techniques used (and developed) to investigate the context of the damage development. Whil much of the information discussed is not complete, it is thought that a description of the experimental methods and experiences will be valuable to the technical community. Included are descriptions of virtually every experimental technique used in this program and a variety of findings not discussed elsewhere.
Download or read book Damage and Failure of Composite Materials written by Ramesh Talreja and published by Cambridge University Press. This book was released on 2012-06-07 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding damage and failure of composite materials is critical for reliable and cost-effective engineering design. Bringing together materials mechanics and modeling, this book provides a complete guide to damage, fatigue and failure of composite materials. Early chapters focus on the underlying principles governing composite damage, reviewing basic equations and mechanics theory, before describing mechanisms of damage such as cracking, breakage and buckling. In subsequent chapters, the physical mechanisms underlying the formation and progression of damage under mechanical loads are described with ample experimental data, and micro- and macro-level damage models are combined. Finally, fatigue of composite materials is discussed using fatigue-life diagrams. While there is a special emphasis on polymer matrix composites, metal and ceramic matrix composites are also described. Outlining methods for more reliable design of composite structures, this is a valuable resource for engineers and materials scientists in industry and academia.
Download or read book The ACEE Program and Basic Composites Research at Langley Research Center 1975 to 1986 written by Marvin B. Dow and published by . This book was released on 1987 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Failure Analysis of Composite Materials with Manufacturing Defects written by Ramesh Talreja and published by CRC Press. This book was released on 2024-02-16 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: In contrast to metals, a composite material acquires an internal structure where the imprint of its manufacturing process history is a significant part of the internal structure’s makeup and in many cases determines how the material responds to external impulses. The performance for which a composite material is designed must therefore be assessed with due consideration to the manufacturing-induced features in the material volume. Failure theories based on homogenized composites cannot deliver reliable methodologies for performance assessment. This book details approaches that depart from traditional treatments by accounting for manufacturing defects in composite materials. It discusses how manufacturing defects are produced and how they affect the performance of composite materials. Serves as the only book to bring knowledge on manufacturing and failure modeling together in a coherent manner. Guides readers on mechanisms-based modeling with a focus on defects. Treats statistical simulation of microstructure with defects aimed at physical modeling. Covers manufacturing methods for polymer matrix composites. Describes failure modes in unidirectional composites and laminates in the presence of defects. Discusses fatigue damage in the presence of defects. This book is aimed at researchers in industry and academia in aerospace engineering, mechanical engineering, and materials science and engineering. It also serves as a reference for students taking advanced courses in composite materials.
Download or read book NASA Reference Publication written by and published by . This book was released on 1977 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Fatigue Damage Development in Graphite Epoxy Laminates written by Russell Douglas Jamison and published by . This book was released on 1982 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of an experimental investigation of damage development in T300/5208 graphite epoxy laminates subjected to tension-tension cyclic loading are reported. The concept of laminate stiffness reduction as a damage analogue is shown to be a valuable means of test control and damage interpretation. The relationship between stiffness and number of cycles is shown to be unique for each laminate type studied, each possessing three distinct stages, but markedly different among the laminate types. By using two complementary nondestructive evaluation (NDE) techniques, edge replication and penetrant-enhanced stereo X- ray radiography along with a method for deploying fatigue-damaged specimens, the stages of stiffness reduction were found to correspond variously to the predominance of matrix cracking or delamination or interactions of these matrix damage modes. A number of subordinate matrix damage modes including interior delamination, microcracking, and longitudinal splitting are identified with the matrix cracks which produce them.
Download or read book Experimental and Analytical Study of Fatigue Damage in Notched Graphite epoxy Laminates written by and published by . This book was released on 1979 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Damage and Failure of Composite Materials written by Ramesh Talreja and published by Cambridge University Press. This book was released on 2012-06-07 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bringing together materials mechanics and modelling, this book provides a complete guide to damage mechanics of composite materials for engineers.
Download or read book The Development of Fatigue Damage Around Fastener Holes in Thick Graphite Epoxy Composite Laminates written by D. S. Saunders and published by . This book was released on 1993 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper discusses the mechanisms by which damage develops and grows around countersunk fastener holes in composite laminates under fatigue loading conditions. Experiments have shown that the erosion of material between ply layers nucleates delaminations which then grow through the laminate under the action of the fatigue loads. The damage at the hole bore surface produces sites for the nucleation of delaminations. The morphology of the delaminations and ply cracking was mapped extensively and from these maps it was found that the volume of material around the fastener hole, .damaged by the fatigue loading, adopted a characteristic shape, the volume of damaged laminate increased towards the faying surface of the laminate and (metal) fixture. This characteristic damage volume was generated by the fastener rocking under the fatigue loads. Growth of the delaminations has been shown to be preceded by intraply cracking and, as fatigue loading proceeded, more delaminations were generated at the hole bore surface. The interfacial region between the composite laminate and the fixture also provided the nucleation site for fatigue cracks in the fasteners. The effects of initial fastener-hole clearances on damage nucleation and growth, . did not appear to follow any clear pattern. However, coupons with excessive initial hole clearances did appear to exhibit greater than expected damage growth after only one sequence block. Composite materials, Mechanically fastened joints, Fatigue loading, Fatigue damage, Damage development, Damage mechanisms, Thick laminates, Graphite/epoxy.
Download or read book Fatigue Life Prediction of Cross Ply Composite Laminates written by IM. Daniel and published by . This book was released on 1989 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue damage development in cross-ply laminates consists of transverse matrix cracking followed by longitudinal matrix cracking, local delaminations at crack intersections, and ultimately longitudinal fiber breakage of the load-carrying plies. Ultimate failure is determined by the manner in which the load is redistributed and transferred into the load-carrying plies. A model was developed for predicting fatigue life of cross-ply laminates which develop transverse cracking up to the characteristic damage state (CDS) level before fatigue failure. The fatigue life consists of two portions: the portion necessary to reach the CDS and the residual life after attainment of the CDS. A procedure for estimating the CDS life is described based on the relationship between residual stiffness and crack density and the stress-life (S-N) curve of the 90° lamina. The residual life after CDS was obtained by calculating the stress carried by the 0° plies and assuming that these plies within the damaged laminate behave like a 0° lamina under cyclic loading. Fatigue life predictions were in good agreement with experimental results for three graphite/epoxy cross-ply laminates.
Download or read book Multiscale Modeling and Simulation of Composite Materials and Structures written by Young W. Kwon and published by Springer Science & Business Media. This book was released on 2007-10-23 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the state-of-the-art in multiscale modeling and simulation techniques for composite materials and structures. It focuses on the structural and functional properties of engineering composites and the sustainable high performance of components and structures. The multiscale techniques can be also applied to nanocomposites which are important application areas in nanotechnology. There are few books available on this topic.
Download or read book Cyclic Deformation Fracture and Nondestructive Evaluation of Advanced Materials written by Michael R. Mitchell and published by ASTM International. This book was released on 1994 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines the initiation and growth of fatigue cracks and the fracture toughness of advanced materials such as silicon nitride, special alloys and steels, thermoplastics, and graphite-epoxy composites; and explains several non-destructive techniques to evaluate such materials for manufacturing defect
Download or read book Advanced Fatigue Damage Development in Graphite Epoxy Laminates written by Russell Douglas Jamison and published by . This book was released on 1982 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of an experimental investigation of damage development in T300/5208 graphite epoxy laminates subjected to tension-tension cyclic loading are reported. The concept of laminate stiffness reduction as a damage analogue is shown to be a valuable means of test control and damage interpretation. The relationship between stiffness and number of cycles is shown to be unique for each laminate type studied, each possessing three distinct stages, but markedly different among the laminate types. By using two complementary nondestructive evaluation (NDE) techniques, edge replication and penetrant-enhanced stereo X- ray radiography along with a method for deploying fatigue-damaged specimens, the stages of stiffness reduction were found to correspond variously to the predominance of matrix cracking or delamination or interactions of these matrix damage modes. A number of subordinate matrix damage modes including interior delamination, microcracking, and longitudinal splitting are identified with the matrix cracks which produce them.
Download or read book Effect of Fatigue Induced Defects on the Residual Response of Composite Laminates written by AL. Highsmith and published by . This book was released on 1984 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper is concerned with the understanding, interpretation, and engineering representation of fatigue damage development in continuous-fiber composite laminates that are fiber dominated, but have significant effects caused by damage in the off-axis plies. It is the objective of this paper to present a description of damage development under tension-tension, tension-compression, and compression-compression cyclic loading that is as complete and generic as possible in the sense that it can be used as a basis for engineering representations and interpretations of the effect of such damage on the strength, stiffness, and life of composite laminates.
