Fatigue Damage-strength Relationships in Composite Laminates. Volume 1

Fatigue Damage-strength Relationships in Composite Laminates. Volume 1 PDF Author: Kenneth L. Reifsnider
Publisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 58

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Book Description
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.

Fatigue Damage-strength Relationships in Composite Laminates. Volume 1

Fatigue Damage-strength Relationships in Composite Laminates. Volume 1 PDF Author: Kenneth L. Reifsnider
Publisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 58

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Book Description
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.

Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 702

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Book Description


The Shock and Vibration Digest

The Shock and Vibration Digest PDF Author:
Publisher:
ISBN:
Category : Shock (Mechanics)
Languages : en
Pages : 618

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Book Description


Advanced Residual Strength Degradation Rate Modeling for Advanced Composite Structures

Advanced Residual Strength Degradation Rate Modeling for Advanced Composite Structures PDF Author: D. E. Pettit
Publisher:
ISBN:
Category : Composite materials
Languages : en
Pages : 348

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Book Description
This report presents the results of the first task of a three task program directed at the study of relationship between damage propagation and residual static strength of composite laminates. In Task 1: Preliminary screening, two laminates a 24-Ply 67% 0 deg. fiber and a 32-Ply quasi-isotropic laminate of T300/5208 graphite epoxy material were selected for study. Two damage types were studied, a low velocity impact condition (i.e., simulated tool drop) and a badly drilled hole. An initial study was conducted for each damage type to determine the detailed damage introduction parameters resulting in the selection of one set of impact and one set of poor drilling conditions. Baseline static tension and static compression tests were conducted on each of the four damage/laminate conditions. Stress vs life (S-N) fatigue data were then generated at range ratio R=-1 for each of the four conditions. The damage growth characteristics were monitored on each fatigue specimen using a modified Holscan ultrasonic unit. A subset of the damaged hole specimens was also evaluated in static compression and fatigue (R = -1) using TBE enhanced X-ray methods to monitor damage growth and to assess any detrimental effect of TBE on subsequent behavior of the damage. The results indicate significant reduction in initial static tension and compression strengths for the damaged hole condition in both laminates.

Composite Materials

Composite Materials PDF Author: Eugene T. Camponeschi
Publisher: ASTM International
ISBN: 0803114982
Category : Composite materials
Languages : en
Pages : 659

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Book Description


Fatigue in Composites

Fatigue in Composites PDF Author: Bryan Harris
Publisher: Elsevier
ISBN: 1855738570
Category : Technology & Engineering
Languages : en
Pages : 765

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Book Description
This major handbook is the first authoritative survey of current knowledge of fatigue behaviour of composites. It deals in detail with a wide range of problems met by designers in the automotive, marine and structural engineering industries. Compiled from the contributions of some of the best-known researchers in the field, it provides an invaluable, practical and encyclopaedic handbook covering recent developments. Comprehensively discusses the problems of fatigue in composites met by designers in the aerospace, marine and structural engineering industries Provides a general introduction on fatigue in composites before reviewing current research on micromechanical aspects Analyses various types of composites with respect to fatigue behaviour and testing and provides in-depth coverage of life-prediction models for constant variable stresses

Cyclic Deformation, Fracture, and Nondestructive Evaluation of Advanced Materials

Cyclic Deformation, Fracture, and Nondestructive Evaluation of Advanced Materials PDF Author: Michael R. Mitchell
Publisher: ASTM International
ISBN: 0803119895
Category : Composite materials
Languages : en
Pages : 405

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Book Description
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

Composite Materials

Composite Materials PDF Author: H. Thomas Hahn
Publisher: ASTM International
ISBN: 0803111908
Category : Composite materials
Languages : en
Pages : 421

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Book Description
Annotation Proceedings of a symposium on [title] held April 1987, Cincinnati, OH. The majority of papers deal with composite systems of thermosetting epoxies. Some attention is given to more recent thermoplastic systems. Annotation copyrighted by Book News, Inc., Portland, OR.

Numerical Analysis and Modelling of Composite Materials

Numerical Analysis and Modelling of Composite Materials PDF Author: J.W. Bull
Publisher: Springer Science & Business Media
ISBN: 9401106037
Category : Technology & Engineering
Languages : en
Pages : 457

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Book Description
Composite materials are increasingly used in many applications because they offer the engineer a range of advantages over traditional materials. They are often used in situations where a specified level of performance is required, but where the cost of testing the materials under the extremes of those specifications is very high. In order to solve this problem, engineers are turning to computer Modelling to evaluate the materials under the range of conditions they are likely to encounter. Many of these analyses are carried out in isolation, and yet the evaluation of a range of composites can be carried out using the same basic principles. In this new book the editor has brought together an international panel of authors, each of whom is working on the analysis and Modelling of composite materials. The overage of the book is deliberately wide; to illustrate that similar principles and methods can be used to model and evaluate a wide range of materials. It is also hoped that, by bringing together this range of topics, the insight gained in the study of one composite can be recognized and utilized in the study of others. Professional engineers involved in the specification and testing of composite material structures will find this book an invaluable resource in the course of their work. It will also be of interest to those industrial and academic engineers involved in the design, development, manufacture and applications of composite materials.

Mechanics of Failure Mechanisms in Structures

Mechanics of Failure Mechanisms in Structures PDF Author: R.L. Carlson
Publisher: Springer Science & Business Media
ISBN: 9400742525
Category : Science
Languages : en
Pages : 102

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Book Description
This book focuses on the mechanisms and underlying mechanics of failure in various classes of materials such as metallic, ceramic, polymeric, composite and bio-material. Topics include tensile and compressive fracture, crack initiation and growth, fatigue and creep rupture in metallic materials, matrix cracking and delamination and environmental degradation in polymeric composites, failure of bio-materials such as prosthetic heart valves and prosthetic hip joints, failure of ceramics and ceramic matrix composites, failure of metallic matrix composites, static and dynamic buckling failure, dynamic excitations and creep buckling failure in structural systems. Chapters are devoted to failure mechanisms that are characteristic of each of the materials. The work also provides the basic elements of fracture mechanics and studies in detail several niche topics such as the effects of toughness gradients, variable amplitude loading effects in fatigue, small fatigue cracks, and creep induced brittleness. Furthermore, the book reviews a large number of experimental results on these failure mechanisms. The book will benefit structural and materials engineers and researchers seeking a “birds-eye” view of possible failure mechanisms in structures along with the associated failure and structural mechanics.