Crashworthiness Energy Absorption of Carbon Fiber Composites PDF Download

Author: Francesco Roberto Deleo
Publisher:
ISBN:
Category : Fibrous composites
Languages : en
Pages : 140

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Author: A.G. Mamalis
Publisher: CRC Press
ISBN: 1351457551
Category : Technology & Engineering
Languages : en
Pages : 270

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Book Description
FROM THE INTRODUCTION Vehicle crashworthiness has been improving in recent years with attention mainly directed towards reducing the impact of the crash on the passengers. Effort has been spent in experimental research and in establishing safe theoretical design criteria on the mechanics of crumpling, providing to the engineers the ability to design vehicle structures so that the maximum amount of energy will dissipate while the material surrounding the passenger compartment is deformed, thus protecting the people inside. During the last decade the attention given to crashworthiness and crash energy management has been centered on composite structures. The main advantages of fibre reinforced composite materials over more conventional isotropic materials, are the very high specific strengths and specific stiffness which can be achieved. Moreover, with composites, the designer can vary the type of fibre, matrix and fibre orientation to produce composites with proved material properties. Besides the perspective of reduced weight, design flexibility and low fabrication costs, composite materials offer a considerable potential for lightweight energy absorbing structures; these facts attract the attention of the automotive and aircraft industry owing to the increased use of composite materials in various applications, such as frame rails used in the apron construction of a car body and the subfloor of an aircraft, replacing the conventional materials used. Our monograph is intended to provide an introduction to this relatively new topic of structural crashworthiness for professional engineers. It will introduce them to terms and concepts of it and acquaint them with some sources of literature about it. We believe that our survey constitutes a reasonably well-balanced synopsis of the topic.

Author:
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ISBN:
Category :
Languages : en
Pages :

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In this investigation the effects of material, structural and testing parameters of carbon epoxy braided composite tubes were analysed with respect to their performance in crush and impact conditions. An original method of manufacturing the composite tubes with vacuum infusion together with an expandable foam core to form multi-cellular structures was used. Low cost, 24k tow carbon fibre braids were used and their performance was compared with that of the more expensive l2k tow size fibres. The specimens produced were axially crushed at constant quasi-static low velocities and at higher impact velocities using an instrumented falling weight machine. Load displacement data gathered from such tests were used to evaluate the test specimens with respect to their specific energy absorption values. The effects of a number of parameters, including fibre tow size, braid architecture, resin content and loading type, were evaluated. From the experimental results analysed from the test specimens it can be concluded that: The 24k fibre showed lower specific energy absorption values than specimens made from l2k fibre; Epoxy resin content rather than epoxy resin type can significantly affect the specific energy absorption values. In general, specimens tested in impact loading exhibited lower specific energy absorption values than the same specimens test in quasi-static crush. A reasonably good correlation between global density and specific energy absorption for the type of structures examined was found.

Author: P. E. Irving
Publisher: Elsevier
ISBN: 0857099183
Category : Technology & Engineering
Languages : en
Pages : 537

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Polymer composites are increasingly used in aerospace applications due to properties such as strength and durability compared to weight. Edited by two leading authorities in the field, this book summarises key recent research on design, manufacture and performance of composite components for aerospace structures. Part one reviews the design and manufacture of different types of composite component. Part two discusses aspects of performance such as stiffness, strength, fatigue, impact and blast behaviour, response to temperature and humidity as well as non-destructive testing and monitoring techniques.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 270

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In passenger vehicles, the ability to absorb impact energy and be survivable for the occupant is called the "crashworthiness" of the structure. The ACC (Automotive Composite Consortium) has been and continues to be very interested in investigating the use of fiber-reinforced composites as crash energy absorbers. It would have been ideal if the composite structure to be used as a crash energy absorber were manufactured as an integral, monolithic component, but limitations in the present day manufacturing technology necessitate the presence of joints in composite structures. While many scientists have investigated the energy absorption characteristics in various fiber reinforced composite materials, there is no literature available on the energy absorption and crushing characteristics of these materials when they are used in a bonded structure. The influence of having a bonded joint within the crush zone of a composite structure has not been adequately characterized in the past. After reviewing the existing literature and based on our own work done in automotive crashworthiness studies it can be concluded that investigating the strain rate dependence of fiber reinforced polymer composites and bonded structures made from them are also very important since the amount of energy they absorb and their performance properties vary with loading rate. The above is the last stage in crashworthiness research, where in one would like to determine how best fiber composite structures can be bonded together in the pursuit of designing the most crashworthy adhesively bonded automotive composite structure. Hence, a comprehensive experimental methodology to analyze and design adhesively bonded automotive composite structures made of carbon fiber polymer composites to sustain axial, off-axis and lateral crash/impact loads is developed and strain rate effects on the crashworthiness of these bonded carbon fiber composite structures are studied. The experimental results from this work are being used to provide the building blocks for model developments - first the coupon level, then progressing in complexity to component level. Correlation with experimental results will provide the basis for which the analytical developments including development of constitutive laws, materials models, damage algorithms and new finite elements, are made.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
In this investigation the effects of material, structural and testing parameters of carbon epoxy braided composite tubes were analysed with respect to their performance in crush and impact conditions. An original method of manufacturing the composite tubes with vacuum infusion together with an expandable foam core to form multi-cellular structures was used. Low cost, 24k tow carbon fibre braids were used and their performance was compared with that of the more expensive l2k tow size fibres. The specimens produced were axially crushed at constant quasi-static low velocities and at higher impact velocities using an instrumented falling weight machine. Load displacement data gathered from such tests were used to evaluate the test specimens with respect to their specific energy absorption values. The effects of a number of parameters including fibre tow size, braid architecture, resin content and loading type were evaluated. From the experimental results analysed from the test specimens it can be concluded that: - The 24k fibre showed lower specific energy absorption values than specimens made from l2k fibre. Epoxy resin content rather than epoxy resin type can significantly affect the specific energy absorption values. In general, specimens tested in impact loading exhibited lower specific energy absorption values than the same specimens test in quasi-static crush. A reasonably good correlation between global density and specific energy absorption for the type of structures examined was found.

Author: Ahmed Elmarakbi
Publisher: John Wiley & Sons
ISBN: 111853526X
Category : Technology & Engineering
Languages : en
Pages : 487

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Book Description
The automotive industry faces many challenges, including increased global competition, the need for higher-performance vehicles, a reduction in costs and tighter environmental and safety requirements. The materials used in automotive engineering play key roles in overcoming these issues: ultimately lighter materials mean lighter vehicles and lower emissions. Composites are being used increasingly in the automotive industry due to their strength, quality and light weight. Advanced Composite Materials for Automotive Applications: Structural Integrity and Crashworthiness provides a comprehensive explanation of how advanced composite materials, including FRPs, reinforced thermoplastics, carbon-based composites and many others, are designed, processed and utilized in vehicles. It includes technical explanations of composite materials in vehicle design and analysis and covers all phases of composite design, modelling, testing and failure analysis. It also sheds light on the performance of existing materials including carbon composites and future developments in automotive material technology which work towards reducing the weight of the vehicle structure. Key features: Chapters written by world-renowned authors and experts in their own fields Includes detailed case studies and examples covering all aspects of composite materials and their application in the automotive industries Unique topic integration between the impact, crash, failure, damage, analysis and modelling of composites Presents the state of the art in composite materials and their application in the automotive industry Integrates theory and practice in the fields of composite materials and automotive engineering Considers energy efficiency and environmental implications Advanced Composite Materials for Automotive Applications: Structural Integrity and Crashworthiness is a comprehensive reference for those working with composite materials in both academia and industry, and is also a useful source of information for those considering using composites in automotive applications in the future.

Author: A. Praveen Kumar
Publisher: Springer Nature
ISBN: 9819952891
Category : Technology & Engineering
Languages : en
Pages : 121

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Book Description
This book summarizes many of the recent advances in the design and application of thin-walled composite protective structures. The past few decades have seen outstanding advances in the use of composite materials in structural applications. Composites have revolutionized traditional design concepts and made possible an unparalleled range of new and exciting possibilities as viable materials for construction. This book presents an extensive survey on recent improvements in the research and development of composites and biocomposites that are used to make structures in various applications. This book deals with design, research and development studies, experimental investigations, theoretical analysis, and fabrication techniques relevant to the application of composites in load-bearing components for assemblies, ranging from individual components such as plates and shells to complete composite structures. This book also focuses the recent advances in biocomposite materials from renewable resources and introduces a potential application of this material. The content is this book benefits the academics, researchers, scientists, engineers, and students in the field of epoxy blends for application as lightweight advanced composite structures.

Author: I.H. Marshall
Publisher: Springer
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 872

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Book Description
The papers contained herein were presented at the Sixth International Conference on Composite Structures (ICCS/6) held at Paisley College, Scotland in September 1991. The Conference was organised and sponsored by Paisley College. It was co-sponsored by Scottish Enterprise, the National Engineering Laboratory, the US Army Research, Development and Standardisation Group-UK, Strathclyde Regional Council and Renfrew District Council. It forms a natural and ongoing progression from the highly successful ICCS/1/2/3/4 and 5 held at Paisley in 1981, 1983, 1985, 1987 and 1989 respectively. As we enter the final decade of this century many organisations throughout the world are adopting a prophetic role by attempting to forecast future scientific advances and their associated impact on mankind. Although some would argue that to do so is folly, without such futuristic visionaries the world would be that much poorer. IntelJigent speculation based on research trends and historical advances, rather than fanciful theories, breathes a healthy air of enthusiasm into the scientific community. Surely this is the very oxygen necessary to ignite the fir~s of innovation and invention amongst pioneers of research.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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In this paper, the crashworthiness characteristics of rectangular tubes made from a Carbon-fiber reinforced Hybrid-Polymeric Matrix (CHMC) composite were investigated using quasi-static and impact crush tests. The hybrid matrix formulation of the CHMC was created by combining an epoxy-based thermosetting polymer with a lightly crosslinked polyurea elastomer at various cure-time intervals and volumetric ratios. The load-displacement responses of both CHMC and carbon-fiber reinforced epoxy (CF/epoxy) specimens were obtained under various crushing speeds; and crashworthiness parameters, such as the average crushing force and specific energy absorption (SEA), were calculated using subsequent load-displacement relationships. The CHMC maintained a high level of structural integrity and post-crush performance, relative to traditional CF/epoxy. The influence of the curing time and volumetric ratios of the polyurea/epoxy dual-hybridized matrix system on the crashworthiness parameters was also investigated. The results reveal that the load carrying capacity and total energy absorption tend to increase with greater polyurea thickness and lower elapsed reaction curing time of the epoxy although this is typically a function of the loading rate. In conclusion, the mechanism by which the CHMC provides increased damage tolerance was also investigated using scanning electron microscopy (SEM).