DAY 35: MAKING COMPOSITE
MATERIALS
Some Matrix Materials
 Manufacturing Methods
 Structural Composites

BOEING 767
AIRBUS A380
http://www.airporttech.tc.faa.gov/safety/patterson2.asp
http://www.hsc.csu.edu.au/engineering_studies/aero_eng/2579/polymer_composites.html
COMPOSITE PROPERTIES (EPOXY MATRIX)
VF=0.6
BORON FIBERS ARE AN UNCOMMON ADDITION –
THEY ARE LARGE AND INFLEXIBLE
Epoxy
Boron
Graphite
http://www.metallographic.com/Procedures/Applications.htm
BORON FIBER - CHEMICAL VAPOR
DEPOSITION ON A TUNGSTEN WIRE
http://www.specmaterials.com/boronfiber.htm
CARBON FIBER (HEXCEL)
http://www.hexcel.com/NR/rdonlyres/225E3CA5-965B-4B29-9A920CE184B1DDF3/0/CarbonFiber_SelectorGuide.pdf
CARBON FIBERS (TORAY)
http://www.toraycfa.com/pdfs/Torayca
SummaryDataSheet.pdf
http://www.fibraplex.com/tow.asp
CARBON EPOXY COMPOSITE PROPERTIES
http://www.hexcel.com/NR/rdonlyres/225E3CA5-965B-4B29-9A920CE184B1DDF3/0/CarbonFiber_SelectorGuide.pdf
COST COMPARISON
MATRIX MATERIALS FOR COMPOSITES

1.
2.
3.
4.

Function and Properties of the Matrix Material
Binding fibers together into a shape
Protect the fibers from damage
Serve as a barrier to failure. If an individual
fiber fails, the failure will not spread.
Be very easy to bond to fiber
The matrix materials are usually polymers and
are the”weak link” as far as operating
temperatures are concerned.
LIST OF MATRIX MATERIALS, SOMETIMES
CALLED “RESINS”
Polyester
 Vinyl ester
 Epoxy
 Phenolic
 PEEK

POLYESTER
Very common polymer family. It can be
thermoplastic and in this form is a common
synthetic fiber.
 Unsaturated polyesters are used in producing
thermosets, (copoymerization with styrene)
which are used as matrix materials.
 Mostly in fiberglass. The bond is strong, and is
particularly good at resisting water and chemical
attack.
 Cheap

VINYL ESTERS

Better than polyester, but a little more expensive.
Gives upper end fiberglass.
Glassair – first
composite kit
airplane.
EPOXY

We have already discussed this one, a top of the
line thermoset, very commonly used in aerospace
composites.
OTHERS
Phenolics, high strength thermosets. Very good
adhesives and high temperature uses.
 PEEK. PEI (polyetherimide) PPS (polyphynolene
sulfide) Very strong. Good at higher
temperatures. This is a thermoplastic. In recent
years, thermoplastic matrix materials have seen
increased use.

Tough,
damage
resistant, can
be welded!
FABRICATION PROCESSES
Pultrusion
 Filament winding
 Prepreg and Lay up

PULTRUSION

Quick, inexpensive way to make long fiber
oriented composites. Fibers oriented. For the
kind of stuff you make by extrusion. Hollow core
is possible.
PULTRUSION IMAGES
http://www.henanpolymer.com/english/frp1.html
http://www.aims-intl.com/images/grating___pultruded.gif
FILAMENT WINDING
Filaments are carefully
wound onto a mandrel
after being wetted with
resin.
 When the desired
number of windings is
obtained, the object
may be cured.
 The manufactured
object will often be
cylindrical in shape.

FILAMENT WINDING IMAGES
http://www.adoptech.com/pressure-vessels/main.htm
http://imghost.indiamart.com/data/T/P/MY-718936/filamentwound-frp-pipes_10676686_250x250.jpg
http://www.gilgwang.com/english/frp/img/grp03.gif
PREPREG AND LAYUP
You will see sheets of prepreg. They consist of the
fiber and the uncured resin, with paper backing.
 The sheets are applied, often by hand to a form,
where they adhere. This is often done by hand, by
expert workers.
 Then cure.

IMAGES
Prepreg must be stored at low
temp. to avoid curing or drying
out.
COMPOSITE MADE BY LAY UP
STRUCTURAL COMPOSITES

Sandwich Composites are an example of how
different parts of a beam, plate or shell structure can
be made in layers, in which each layer performs a
function.
•SANDWICH
TYPES OF HONEYCOMB
Aramid Fiber
(Nomex®/Kevlar®)
 Aluminum
 Stainless Steel
 Thermoplastic







Polycarbonate
Polypropylene
PVC
SAN
PE
ABS
http://www.plascore.com/product-honeycomb-cores.htm?gclid=CJK_5_HP6p8CFQoNDQodExVGYg
http://www.azom.com/details.asp?ArticleID=1092#_Honeycombs
APPLICATION: TOYOTA EAGLE 987
Fuselage is carbon fiber honeycomb composite
GLARE
GLARE is used in aerospace structures. It is a
composite in which layers of aluminum and
fiberglass prepreg sheets are bonded together by
epoxy.
 Why not use carbon fiber?
 The fibers are aligned in a way which is most
favorable for load carrying.
 Once fabricated, GLARE is then processed in
much the same way that aerospace aluminum is.

GLARE IMAGES (HYBRID COMPOSITE)
Outer layers of
Aluminum act
as protective
barriers.
Water
absorption can
be a problem.
Here is reduced
USE OF GLARE