[ NEW MULTI-AXIAL CARBON-FIBRE CONCEPT OPENS ROUTE ]

Multi-disciplinary co-operative studies involving naval engineers, uni
versity staff and industrial carbon fibre technologists in Norway, Swe
den and Japan have resulted in the development of a new multi-axial re
inforcement that, when laid up as sandwich laminates with a pvc foam-c
ore, fully meets the strength and stealth requirements of modern high-
speed naval vessels while permitting ships to be built by the “sectio
nal” method normal to metal construction.
The first use of the new technology in large vessel construction is on
order from the Swedish Navy for two 71meter ships ― the largest ever
carbon-fibre construction ― to be built by Karlskronavarvet AB in Sw
eden, with an option for two further vessels.
Experience gained from aearlier Swedish Navy order for 39 combat boa
ts, each of 11m, currently being built at Storebro Royal Cruser AB, wi
ll be invaluable in constructing the large vessels during 1996 and 199
7.
While the theortical strengh of fibres is well acknowledged, approach
to achieving that strength in practice is a function of initial fibre
quality, fibre orientation, and integrity of the resin/fibre composite
. Until now, discontinuities - such as fibre twists, entrapped air and
uneven wetting - have seriously affected attained strength properties
. In consequence, while carbon fibres have been developed to increasin
gly higher specific strength and specific modulus of elasticity over t
he years, the attained strength/cost ratio of composites made from the
m has restricted their use to very small, highly specialised, products
.