Download 6. Glossary of Terms

Glossary
6.
Glossary of Terms
Anisotropic binding structure
Brooming
Brushing
Carbonising
Cellulose
Charged coupled device
Chemical polymerisation/shrinkage
Chromatic aberration
Class A surface
Crimping
Debaulked
Exotherm
Fibre buckling
Fibre bundles
C A Squires
The binding structure differs along the
line (or direction, x, y, z) that is being
measured.
Transverse splitting of the composite.
Slight application of load to the test
specimen.
Fibres heated to high temperatures
(3000°C) without oxygen. With no
oxygen the fibres cannot burn, instead
the high temperatures cause the atoms
to vibrate violently until most the noncarbon atoms are expelled.
A complex carbohydrate, (CHO), that is
composed of glucose units, forms the
main constituent of the cell wall in most
plants, and is important in the
manufacture of numerous products, such
as paper, textiles, pharmaceuticals, and
explosives.
A charge-coupled device (CCD) is a lightsensitive integrated circuit that stores and
displays the data for an image in such a
way that each pixel (picture element) in
the image is converted into an electrical
charge the intensity of which is related to
a colour in the colour spectrum.
This is when the molecules in the resin
bond during the cure cycle causing
volumetric shrinkage of the resin.
Is caused by a lens having a different
refractive index for different wavelengths
of light (the dispersion of the lens).
It is a term used to characterised an
aesthetic surface finish in the automotive
industry as a perfectly polished, high
lustre surface, free from porosity and
scratches of any kind
Waviness is present in the carbon fibre
fabric
Placing the laminate stack under vacuum
pressure at room temperature to displace
any air entrapment.
Describes a process or reaction that
releases energy in the form of heat.
The bending of a fibre under a given
force.
See Tow.
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Glossary
Fibre kinking
Fibre misalignment/mis-orientation
Fibre volume fraction
Fibre waviness
Filament
Gel point
Glass transition temperature
Hydroscopic
Hygrothermal
Interface debonding
Kink bands
Long wave defects
Microbuckling (elastic/plastic/shear)
Non-visible spectrum
Original equipment manufacturer
Oxidising
C A Squires
A fibre with a geometric anomaly in the
length mostly due to external factors.
When the fibre is off-axis of its designed
path.
The ratio of fibre volume to matrix volume
within a given laminate.
A fibre that has a formed a wave shape
rather than the nominal aligned form.
The individual thread of carbon fibres that
come together to form a tow.
Stage at which, a liquid begins to exhibit
elastic properties and increased
viscosity.
The glass transition temperature is the
temperature, below which the physical
properties of amorphous materials vary in
a manner similar to those of a crystalline
phase (glassy state), and above which
amorphous materials behave like liquids
(rubbery state).
Is the ability of a substance to attract
water molecules from the surrounding
environment through either absorption or
adsorption.
Separation occurring at the meeting point
of the fibres and the matrix.
A group of fibres with a geometric
anomaly in the length mostly due to
external factors.
Long-term waviness is generalised as
wavelengths () that are greater than
10mm.
Localised buckling of the composite
laminate in elastic mode/plastic mode
and shear (45°)
This is used to quantify the sharpness of
the given image (the dullness).
Term used in automotive manufacturing
for the original supplier of the
components used in the construction of a
vehicle
This is heating the fibers in air to about
200-300° C for 30-120 minutes. This
causes the fibers to pick up oxygen
molecules from the air and rearrange
their atomic bonding pattern, prior to
carbonising.
242
Glossary
Pin holing
Polyacrylonitrile polymer fibres
Porosity/voids
Print through
Short wave defects
Sink marks
Spectrometer
Spectrophotometer
Teddy bears ears
Thermal shrinkage
Thermocouple
Thermoplastics
Thermosets
Tow
Transverse rupture
Visco-elastic nature
Visible spectrum
C A Squires
A small hole in the surface of a laminate.
A synthetic polymer used in the
manufacture of artificial fibres
A volume within a composite laminate
where there is no fibre or resin present
Is the effect on the surface of a laminate
due to the volumetric shrinkage in the
matrix due to polymerisation
Short-term waviness is formed from
surface anomalies (i.e. porosity/print
through etc.), with wavelengths between
1 and 3mm in length and commonly
below 1mm in amplitude
Defect in the Class A surface that has not
caused breaking of the surface resin.
A spectroscope equipped with scales for
measuring wavelengths or indexes of
refraction.
An instrument used to determine the
intensity of various wavelengths in a
spectrum of light.
Surface distortion on the Class A surface
of CBS 95 surrounding the vents on a
DB9 bonnet.
Reverse thermal expansion.
A thermoelectric device used to measure
temperatures accurately, especially one
consisting of two dissimilar metals joined
so that a potential difference generated
between the points of contact is a
measure of the temperature difference
between the points.
Polymers that can soften and then can
be shaped with the addition of heat.
Polymers that acquire their final shape
after an irreversible process.
A tow is filaments of carbon fibres, often
in multiples of 6,000 up to 48,000.
Due to differences in Poisson’s ratios of
the material constituents and non uniform
distribution of transverse strains over the
specimen length
Viscoelasticity, also known as
anelasticity, describes materials that
exhibit both viscous and elastic
characteristics when undergoing plastic
deformation.
The visible spectrum (or sometimes
optical spectrum) is the portion of the
electromagnetic spectrum that is visible
243
Glossary
Warp yarn
Weft yarn
Worm tracks
C A Squires
to (can be detected by) the human eye.
Warp uses a needle that loops its own
thread. The needles produce parallel
rows of loops simultaneously that are
interlocked in a zigzag pattern.
Weft differs from warp as it uses one
continuous yarn to form courses, or rows
of loops, across a fabric
These are localised rows of voids found
at the edge of DB9 bonnet.
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