Composite Materials Research Progress

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W.H. Zhong, R.G. Maguire, S.S. Sangari et al.
impact resistant and damage tolerant structure. Various means of accomplishing this have
ranged from elastomeric/thermoplastic minor phases to discrete layers of toughened materials.
Nano-modified polymeric matrices are mostly involved in the development trends for matrix
polymer materials. Technology for enhancing the interfacial adhesion properties between the
reinforcement and matrix for a composite to provide high stress-transfer ability is more
critically demanded and the science of the interface is expanding. Fiber/matrix interfacial
adhesion is vital for the application of the newly developed advanced reinforcement materials.
Effective approaches to improving new and non-traditional treatment methods for better
adhesion have just started to receive sufficient attention. Multi-functionality is also an
important trend for advanced composites, in particular, utilizing nanotechnology
developments in recent years to provide greater opportunities for forcing materials to play a
more comprehensive role in the designs of the future.
More reliable and low cost manufacturing technology has been pursued by industry and
academic researchers and the traditional material forms are being replaced by those which
support the growing need for high quality, rapid production rates and lower recurring costs.
Major trends include the recognition of the value of resin infusion methods, automated
thermoplastic processing which takes advantage of the unique advantages of that material
class, and the value of moving away from dependence on the large and expensive autoclaves.
Introduction
In sectors such as aerospace, wind energy, power transmission, marine, automotive and
trucking, composites have been moving into the primary structure of wings, fuselages,
chassis, hulls, and towers. In products such as sports goods and equipment, medical
equipment, civil infrastructure, and dentistry composites are contributing to a market growth
that will soon relegate homogeneous and isotropic materials to a niche category. The word
“composite” is becoming synonymous with greater design flexibility and optimized materials
utilization, leading to more opportunities for monolithic structural designs, less fasteners and
holes, optimization of overall structural element architecture, improved fatigue and corrosion
behavior, and high efficiency and maintainability. Composites are also particularly suitable
for structural health monitoring systems with the associated advantages of reduced
conservatism in designs.
As they have evolved over the past several decades, composites now are spreading out
and leaving their early material forms and traditional processes, and incorporating new
constituents from nano particles to smart additives to hybridizing to capture the best of all
technologies. This has led to lean and efficient automated processes that will enable these
new developments to be cost-effective in production and performance-enhanced in products
that serve us all.
Over the past several decades polymeric composites have matured and evolved,
sometimes fitfully, but much of the time in a steady development driven by the increasing
awareness among industries of the values available from combinations of matrices and fibers.
The world of aerospace has been one of the strongest proponents of advanced composites,
eventually converging on a combination of carbon fibers and thermosetting materials as the
preferred choice for the harsh environment and complex loading of aerostructures. Structural
materials applied for airplane structures from metallic materials, to composites and then nanomodified
composite materials are being developed, see Fig. 1.