The use of Composite Materials in Aerospace, Wind Power and Automotive Technologies

Introduction
A composite is a multiphase heterogeneous material comprising of fibres that are embedded in a matrix [1], [2]. A composite is unlike an alloy because in an alloy, the other components have been produced by naturally occurring changes. There is a diversity of types of composites currently available, since “it is possible to design materials with property combinations that are better than those found in the metal alloys, ceramics and polymeric materials” [3]. The main ones focused on in this essay are polymeric matrices, metal matrix composites and ceramic composites, and their applications in the aerospace, automotive and wind industries.
(1) Brief Fundamentals of Composites
1.1 Concise History [4]
The search for alternative materials arose from growing technological and environmental demands for more efficient and sustainable components for industrial purposes. It was in the 1940s when the military first placed a priority on finding more high-strength and lightweight materials for their vehicles. The main materials used at that time were metallic, and while they were functional, they were often prohibitively heavy, so that the engines could not carry as much as cargo as they preferred, whereas the composite materials were much less heavy, as shown in Table 1, and when compared to non-composites, even steel, carbon based composites have a higher tensile strength. At the bottom of the table is a polymer, with the lowest comparative tensile strength.

Table 1: Mean comparisons of several composite materials against several non-composite materials. Information cumulated from various sources: http://www.matweb.com/tools/weightcalculator.aspx, http://www.onlinemetals.com/calculator.cfm, http://www.azom.com,