Benchmarks For Composite Delamination

Davies, G A O

First Published - November 2002
Softback Report - 35 Pages

High performance composite materials have been in use for 20 years in the Aerospace industry. The specific stiffness of carbon fibre reinforced plastics is unmatched by any metal, and most agile and high speed military aircraft could not have met their specification without using it. The expense has restricted their use, outside Aerospace, to rather specialist areas like sporting goods, racing cars, medical equipment, nuclear fuel processing and the like. Hybrid structures have also been effective, using carbon composite skins as a way of rescuing aging concrete structures. However the costs of the basic materials and their processing have come down of late and the engineering community has also realized that composite structures may actually be cheaper due to the small number of parts compared with traditional metal structures assembled from many components. The buzz word is ‘unitisation’.

Any form of transport will benefit from being light, as fuel costs and environmental pressures begin to bite, and mass produced cars will contain more composites, probably thermo-plastics. These can be formed quickly from cured flat sheets, in contrast to thermosets in which the fibres and the resin are brought together and cured in an autoclave or heated press. The use of composite structures represents a challenge to the designers and finite element community because their strengths and failure modes are not as easy to predict as in metals.

This is the reason for this report and the research programme which underpinned it.

Contents

INTRODUCTION

THE NEED FOR BENCHMARKS

BENCHMARKS
Benchmark 1(A)
Benchmark 1(B)
Benchmark 2
Benchmark 3

REFERENCES
Benchmark specifications
Figures 1-14