Multifunctional Composites

Multifunctional composites include all composites which provide more than one property, or functionality, whether specifically designed or modified from existing designs. Although traditional polymer matrix composites have many useful properties including durability, these often involve tradeoffs such as poor acoustic damping. By designing multifunctional composites, new and enhanced functionalities can complement the existing high-stiffness and high-strength densities of composites....
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Multifunctional composites include all composites which provide more than one property, or functionality, whether specifically designed or modified from existing designs. Although traditional polymer matrix composites have many useful properties including durability, these often involve tradeoffs such as poor acoustic damping. By designing multifunctional composites, new and enhanced functionalities can complement the existing high-stiffness and high-strength densities of composites. Furthermore, multifunctional composites can feature entirely original functionalities, such as self-healing and microvascular transport, which do not exist in classical composites. Among the flaws of traditional composites are lower conductivity and higher contact resistance than aluminum. This complicates efforts to provide aircraft with shielding, grounding, and protection from electromagnetic phenomena such as lighting strikes.Laminated composites are also susceptible to damage when subjected to low velocity impact, resulting in reduced after impact (CAI) strength. In applications such as aircraft, rotorcraft, windmills, and missiles, erosion has major negative effects. Erosion by rain and sand roughens surfaces of classical composites, reducing aerodynamic performance, optical and radiation transmission, and even compromising structural integrity. In addition, traditional composites' high stiffness-to-weight ratio facilitates the spread of acoustic and mechanical vibration within aircraft, leading to passenger discomfort and even mechanical damage. In this book, alternative materials that mitigate these effects are thoroughly described from design to application.Self-healing composites can now remedy many types of damage, including intralaminar cracking, delaminations, erosion, and damage to anti-corrosion coatings. Composites endowed with microvascular transport can deliver healing agents, coolants, or refrigerant fluids throughout the material.Developments in nanotechnology include lower gas permeability, improving storage tanks, food packaging, anti-corrosion coatings, fire resistance, and thermal protection systems.New methods for increasing the fire resistance of composites and thermal protection systems are also thoroughly explored. Finally, an analysis of multifunctional composites with innovative excitation-response capabilities concludes the book.