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KOMPOSIT
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  Section 12 Composites Materials and Technologies E Bayraktar,  Supmeca-Paris, Paris, France r 2016 Elsevier Inc. All rights reserved. Introduction In general meaning, composites are classi 󿬁 ed as a relatively new family of materials characterized by lighter weight and greater strength than conventional materials. The research in processing of the composite materials for their applications in advancedmanufacturing engineering systems are ongoing. Today, new design considerations in modern technologies are completely dif-ferent from conventional ones. For example, in conventional design considerations, lifetime of the materials is predicted as 10 6 numbers of cycles used in usual manufacturing engineering whereas in modern technologies, lifetime of the new materials-composites such as high speed train, new aircraft design, aerospace applications, new gas turbines, etc. is predicted as 10 10 – 10 11 or even more.In classical meaning, composite materials as structural materials in engineering applications include metal matrix composites(MMCs), polymer matrix composites (PMCs), ceramic based composites (CMCs), and also composite materials aimed for building applications. Many composites used today are at the primary advantage of materials technology, with their performanceand costs suitable to ultra-challenging high technological applications. But heterogeneous materials combining the best char-acteristics of dissimilar components have been used by nature for millions of years. Ancient society, reproducing nature, used thisapproach as well. Very simple examples can be seen in the Book of Exodus that describes preparing the composites by ancient society. Essentially, processing of composite materials is an art and science of producing metal or metallic powders, and using them to make  󿬁 nished or semi 󿬁 nished products. For this reason, this particulate technology is probably the oldest processing technique known to man. There are a number of archeological evidences, from Neolithic age and then from Egyptians, Roman,and Greek civilizations to our modern age, to prove that the ancient man knew something about it. However, scientists accept that modern age of composite materials and their processing began when engineers replaced the carbon  󿬁 lament in the Edison lamp. These examples show us the importance of the composites in modern society and usage of high technologies in our daily life,thanks to composites. More research is needed for developing composites to adapt to new demands of the modern technologies.For this reason, composite technologies are fundamental for the development of manufacturing engineering applications. Thecomposite processing and its usage in industrial applications require interdisciplinary scienti 󿬁 c knowledge related to the different scienti 󿬁 c domains such as physics, chemistry, electronics, computer science, and essentially materials science. Therefore, we havetried to present a comprehensive work that can be used as a widespread reference by everybody requiring materials science andmanufacturing and interrelated scienti 󿬁 c and technological information about the composites. It is required that the manu-facturing engineers work with the materials designers  –  feedback coming basically from scienti 󿬁 c research. If the composite designcan be intended carefully and the composite parts can be produced correctly, composite technologies will become much easier andcheaper, and both the quality and evidently the reliability of the composite product can be improved. As for the relation between matrix and reinforcement elements, a very interesting scienti 󿬁 c history should be considered. All of these outstanding aspects of the composites discussed above come from the relation and the behavior of the matrix continuousphase and reinforcing and interface conditions between them when they are processed. As is well known, the continuous phase is the matrix, which is a polymer, metal, or ceramic, etc. Polymers have low strengthand stiffness, metals have intermediate strength and stiffness but high ductility, and ceramics have high strength and stiffness but are brittle. As a continuous phase, the matrix achieves numerous critical functions, including maintaining the  󿬁 bers in the proper direction and arrangement in space and protecting them from abrasion and the environment. Reinforcement elements can bedivided into three classes: particle reinforced, short   󿬁 ber reinforced, and continuous  󿬁 ber reinforced elements. Among these threeclasses, the manufacturing cost of particulate reinforced MMCs is low, which makes it attractive and commercially viable toconsider for industrial applications.In case of polymer and MMCs that have a strong bond between the  󿬁 ber/reinforcement and the matrix, the matrix conveysloads from the matrix to the  󿬁 bers  –  reinforcements through shear loading at the interface. However, in ceramic matrix composites,the main objective is to increase the toughness rather than the strength in regular way; therefore, a low interfacial strength bond isrequired. Evidently, the type and quantity of the reinforcement determine the  󿬁 nal properties. In summary, the reinforcements areadded into the matrix material in order to improve the mechanical properties of composites. On the other hand, the use of singlereinforcement in a matrix may occasionally affect the other mechanical as well as physical properties of the composites. In order toovercome this dif  󿬁 culty, two reinforcements are principally added to the matrix material to produce the hybrid composites. As ageneral rule, the smaller the diameter of the reinforcement/ 󿬁 ber, the higher its strength, but often the cost increases as the diameter becomes smaller. In addition, smaller-diameter high-strength  󿬁 bers have greater   󿬂 exibility and are more amenable to manu-facturing processes such as weaving or forming over radii. Typical  󿬁 bers include glass, aramid, and carbon, which may becontinuous or discontinuous. Reference Module in Materials Science and Materials Engineering doi:10.1016/B978-0-12-803581-8.04108-4  1   As for MMCs, here, a typical example should be the aluminum metal matrix composites (AMMCs) that are being considered asa group of new advanced materials for its light weight, high strength, low thermal expansion coef  󿬁 cient, and good wear resistance,especially very huge reserve exists as row materials in the world. Aluminum matrix composites have been prepared very easily for  various applications in aeronautic-aerospace, automotive, military and electronic industry due to their exceptional properties. Onemay indicate that MMCs adjust the best properties of the two components, such as ductility and toughness of the matrix and highmodulus and strength of the reinforcements. These clear and visible properties of these materials allow them to be the prospectivecandidate for numerous applications such as automotive, aerospace and military, electronics industries, etc. Additionally, processing of the MMCs can be of two types: solid state and liquid state processing. Solid state processing ischaracteristically a powder metallurgy-based process, in which the matrix powder and reinforcement particles are mixed together and compacted to form a bulk shape. Microstructure and  󿬁 nal properties of solid state processing can be controlled very easily andprocessed very economically when compared to liquid phase sintering. Many detailed information can be found in this volumeand many attractive and alternative technologies on the composites will be discussed in detail in different chapters of this volume.Section 12 of   Reference Module in Materials Science and Materials Engineering   as a Comprehensive Materials Processing   ‘  Work  ’ edited by Professor Saleem Hashmi (the  ‘ Editor-in-Chief  ’ ) represents a comprehensive work for this series as a practical library andscienti 󿬁 c source which is dynamic in nature, being periodically updated, and it is arranged to meet the needs of the materialsscience and manufacturing community. There are about seven different basic levels containing different chapters which address general information and basic methodsof composite materials and composite technologies as an essential scienti 󿬁 c area, outlined below:In the 1st basic level,  ‘ General Classi 󿬁 cation of Composites ’  is discussed and details of subbasic levels are as follows:Composites-Overview, MMCs, Ceramic Matrix Composites (CMCs), PMCs, and Hybrid Composites.In the 2nd basic level,  ‘ Microstructural Design of Composites, ’  sublevels discussed are as follows: Effect of Microstructure Variables (MMC – PMC – CMC – Hybrids), Type of Reinforcements and Matrices, Reinforcement Architecture, and Reinforcement/Matrix Interface (bond strength).In the 3rd basic level,  ‘ Production and Processing  ’  is discussed under three sublevels with different chapters: Powder Processing Practice for MMCs, Powder Processing Practice for PMCs, and High-temperature Composites: Processing and Properties.In the 4th basic level,  ‘ Manufacturing and Implementation of Composite Materials ’  are discussed in general way as Manu-facturing Process Selection for Composite Components and Joining of Composites.In the 5th basic level, Design and Applications of Composites is discussed under   󿬁  ve sublevels with different chapters asfollows: Composites in Automotive Applications: Design Concepts, Industrial Applications of Ceramic Matrix Composites,Composites in Aeronautic and Aerospace Applications, Design Concepts Composite Applications Advanced Composites, and Applications and Design Concepts for Railway-Train-High Speed Train.In the 6th basic level,  ‘ Damage Analyses of Composite Structures ’  is discussed with very rich chapters under the sublevels asfollows: Damage Analyses of MMCs, Damage Analyses of Ceramic Matrix Composites, Damage Analyses of PMCs, and Damage Analyses of Hybrid Composites.In the 7th basic level,  ‘ Novel Composites from Recycled Materials and Their Environmental Effects ’  are discussed in thefollowing sublevels: Recycled MMCs. Recycled Ceramic Matrix Composites, and Recycled PMCs. Concluding Remarks and Acknowledgment  This Section 12 presents a collection of very rich chapters related to aspects of general information and methods of compositematerials and composite technologies. Putting together a volume as a successful work of this scale is a skillful endeavor and couldnot have been achieved without the contribution and hard work of the authors of the chapters of this volume. The editor conveyshis deep appreciation to all the authors and coauthors of the actual articles of this Section for their contribution in preparing their individual subjects. Their hard work is gratefully acknowledged. And  󿬁 nally, my deep and sincere acknowledgments to Professor Saleem Hashmi, the Editor-in-Chief of   Reference Module in Materials Science and Materials Engineering   as a Comprehensive Materials Processing   ‘  Work  ’  for the role he has played as a driving force to edit and help us to  󿬁 nish each Section. Special thanks are also to the coordinating staff members of ELSEVIER of thismassive work and to the ELSEVIER editorial staff. 2  Section 12 Composites Materials and Technologies
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