Overview

Abstract

In the continuing quest for improved performance, which may be specified by various criteria including less weight, more strength and lower cost, currently-used materials frequently reach the limit of their usefulness. Thus materials scientists, engineers and scientists are always striving to produce either improved traditional materials or completely new materials. Compos ites are an example of the latter category.Not that composites are really new. A composite is a material having two or more distinct constituents or phases and thus we can classify bricks made from mud reinforced with straw, which were used in ancient civilizations, as a composite. A versatile and familiar building material which is also a composite is concrete; concrete is a mixture of stones, known as aggregate, held together by cement. In addition to synthetic composites there are naturally occurring composites of which the best known examples are bone, mollusc shells and wood; bone and wood are discussed later in the chapter.Within the last forty years there has been a rapid increase in the production of synthetic composites, those incorporating fine fibres in various plastics (polymers) dominating the market. Predictions suggest that the demand for composites will continue to increase steadily with metal and ceramic based composites making a more significant contribution (Figure 1.1).The spur to this rapid expansion over the last few decades was the development in the UK of carbon fibres and in the USA of boron fibres in the early 1960s. These new fibres, which have high elastic constants, gave a significant increase in the stifTness of composites over the well-established glass fibre containing materials, and hence made possible a wide range of applications for composites. One of the key factors was the very high strength-to-weight and stifTness-to-weight ratios possessed by these new composites (section 1.6). Early employment in aviation has led, in more recent times, to wide use in other areas such as the leisure and sports

Micrographs of Fractured Vinyl Ester Composites

“…This shrinkage is particularly serious if the fiber composite components are large. It can be more than ten percent in volume, which is much higher than claimed by some researchers and resins' manufacturers [1,2]. The main drawback of this shrinkage in a composite component is to have stresses set up internally.…”

Overview of Wood Plastic Composites: Focusing on Use of Bio-based Plastics and Co-extrusion Technique

“…Wood flour is considered as an effective reinforcing filler for WPCs because it has a special characteristic bearing a majority of the applied load in filled plastic composites compared to wood particles (Matthews and Rawlings 1999). Hence, wood flour is preferred as one of the widely utilized wood fillers in WPCs.…”

Prediction of Frictional and Wear Behavior of Aluminium Matrix Composites by Artificial Neural Network

“…ANN helps to solve the problems that require interpretation of relationships among the variables of high-dimensional space. [11][12][13] With the advancement in the computing technique researchers are now focusing on use of ANN to predict the mechanical and tribological behavior of composite materials. However, meager information is available as regards prediction of tribological characteristics of Aluminium based TiB 2 reinforced MMCs.…”