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results obtained from the above section is analysed and related with the theory. The results are then analysed with the graphs obtained from the tabulated results. Any difficulties and anomalies if occurred were discussed with proper reasoning and passed over to the next section for conclusion.

1.3.8 Conclusion

This section considers all the sections above. The process and techniques used were analysed and proper conclusion is made from the available data. To improve the quality of the report, recommendations were made in the following section of study.

1.3.9 Recommendations

In this final part of study, suggestions are drawn to improve the nature and standard of this project by comparing the conclusion and discussion. In this section any improvements that can be done is put forward and described.

第二章-Chapter 2

2 文学观点-2 Literature Review

2.1 Introduction

Composite materials are made of fibres and matrix. In composite materials fibres are commonly known as reinforcement. Fibres are strong and stiff. But fibres alone cannot maintain a shape. They are weak in compression and strong in tension. The matrix material is reinforced with the fibres to form the composite material. Together with the matrix material, fibres can hold a shape and can be machined, drilled and glued. When load is applied to the composite material the matrix system transfer the load to the fibres and as a result the load will be distributed evenly along the composite material.

The fibres that are used commonly for commercial purpose are glass, carbon and Kevlar. Usually the fibres are incorporated into a matrix material in continuous lengths or in discontinuous lengths. The matrix material can be polymer, a metal or a ceramic. In structural applications fibre-reinforced composites are used in laminate form. The fibres and matrix are stacked into a number of layers to achieve desired thickness and the final product obtained after the stacking sequence is the laminates. The physical and mechanical properties of the composite laminates can be adjusted by varying the fibre orientation as well as the stacking sequence of various layers [1].

2.1.1 Fibres

Fibres are the main constituent in a fibre-reinforcement composite material. In a composite material, fibres occupy the major volume fraction. The main portion of the load acting on a composite material is on the fibres. The proper selection of the type, amount and orientation of fibres is very important, because it influence the following features of a composite laminate [1].

Specific gravity

Tensile strength and modulus

Fatigue strength and fatigue failure mechanism

Compressive strength and modulus

Electric and thermal conductivities

Cost

A wide range of fibres are available for use in composites. Glass fibres have been in use since the 1930s. But only in the late 1950s the fibres which demonstrate significantly higher stiffness were developed for structural applications. The high specific stiffness and high specific strength fibres are known as advanced fibres. Composites made from advanced fibres are called advanced composites [8].

The first advanced fibre developed for application in structural composites wa