UT TENSIO, SIC VIS THE EXTENSION IS PROPORTIONAL TO … · fiberglass 7.000 1 e 06 fiberglass...

UT TENSIO, SIC VIS

“THE EXTENSION IS PROPORTIONAL TO THE FORCE”

Max y = W L3/ 3 E I

ENGINEERING MATERIALS

DENSITY KG/M3

FIBERGLASS 1.800

CARBON FIBER 1.500

ALUMINIUM 2.700

STEEL 7.500

ENGINEERING MATERIALS

MODULUS OF

ELASTICITY

MPA

PSI

FIBERGLASS 7.000 1 E

06

FIBERGLASS INFUSION 35.000 5 E

06

CARBON FIBER 150.000 22 E

06

ALUMINIUM 70.000 10 E 06

STEEL 200.000 30 E 06

WEIGHT x VOLUME FRACTION

LAMINATE THICKNESS

40%

60% 60% 65%

70%

60%

40% 40% 35%

30%

0%

20%

40%

60%

80%

100%

HAND LAYUP VACUUM BAG INFUSÃO PRÉ PREG AUTOCLAVE

Fibra Resina RESIN FIBRE

FIBRE WEIGHT CONTENT X MANUFACTURING PROCESS

HOW MUCH REINFORCEMENT?

WEIGHT FRACTION

Used in manufacture and refer to fibre or resin weight

percentages.

Manufacturers will specify a glass content of (e.g.) 25 wt%

a prepreg supplier might give a resin content (e.g) of 34

wt%.

VOLUME FRACTION

Used in structural design to calculate composite properties

and almost always refers to fibre volume content.

WEIGHT FRACTION

X

VOLUME FRACTION CONVERSION

For the special case of a two-component composite (fibre and

matrix)

0,00

0,10

0,20

0,30

0,40

0,50

0,60

0,70

0,80

0,90

1,00

0,00 0,05 0,10 0,15 0,20 0,25 0,30 0,35 0,40 0,45 0,50 0,55 0,60 0,65 0,70 0,75 0,80 0,85 0,90 0,95 1,00

FIBRE VOLUME FRACTION

FIBRE WEIGHT FRACTION

GLASS HS CARBON ARAMID

VOLUME FRACTION X WEIGHT FRACTION CONVERSION

(EPOXY RESIN MATRIX)

A composite cannot contain 100% fibre. Maximum volume fraction could be

achieved only if unidirectional fibres are hexagonally ‘close packed’. The

triangular unit cell has area R2 3 The unit cell contains an area of fibre (three 60o segments) equal to πR2 / 2

2R

3R

MAXIMUM FIBRE VOLUME FRACTION

R 3

In a unidirectional fibre composite the fibre area fraction is

the same as the fibre volume fraction:


For other forms of reinforcement, maximum volume fraction also depends on the detailed arrangement of the fibres. Unidirectional 0.70 – 0.72 Stitched ‘non-crimp’ 0.60 – 0.65 Woven Fabric 0.40 - 0.55 Chopped Strand Mat 0.15 - 0.25


Commercial reinforcements are characterised by their areal weight (Aw). This is simply the weight (usually given in grams of 1 m2 of the reinforcement (gr/m2).

Aw depends on many factors - fibre density, tow or bundle

size, weave style, etc. Aw may range from 50 g/m2 or less (for

lightweight surfacing tissues), up to more than 2000 g/m2 for

some heavyweight non-crimp fabrics.


The thickness of a composite laminate depends on the amount of

reinforcement and the relative amount of resin which has been

included. For a given quantity of reinforcement, a laminate

with a high fibre volume fraction will be thinner than one

with a lower fibre volume fraction, since it will contain less

resin.

LAMINATE THICKNESS






resin.

LAMINATE THICKNESS

FIBRE

MATRIX

HIGH MATRIX CONTENT=LOW FIBRE CONTENT =THICK

LAMINATE






resin.

LAMINATE THICKNESS

FIBRE

MATRIX

HIGH MATRIX CONTENT=LOW FIBRE CONTENT =THICK

LAMINATE

LOW MATRIX CONTENT = HIGH FIBRE CONTENT = THIN

LAMINATE

0

20

40

60

80

100

0 0,5 1 1,5 2

FRAÇÃO EM VOLUME (%)

PRESSÃO DE MOLDAGEM (ATM)1/2

Mat Vidro

WR Vidro

Biax Vidro

WR Carbono

Uni Carbono

COMPRESSIBILIDADE DAS FIBRAS FRAÇÃO EM VOLUME

Fibre volume fraction is inversely proportional to

laminate thickness.

If the fibre content and laminate

thickness are defined, we can

calculate the fibre volume

fraction:

If the fibre content and volume

fraction are defined, we can

calculate the laminate thickness:

LAMINATE THICKNESS

0

0,2

0,4

0,6

0,8

1

1,2

1,4

1,6

0,2 0,25 0,3 0,35 0,4 0,45 0,5 0,55 0,6 0,65 0,7 0,75 0,8

PLY THICKNESS (MM)


100 g/m2 150 g/m2 200 g/m2 300 g/m2 500 g/m2

PLY THICKNESS X FIBRE VOLUME FRACTION (HS CARBON)

RULES OF MIXTURE AND

ELASTIC PROPERTIES

'Rules of Mixtures' are mathematical expressions which give

some property of the composite in terms of the properties,

quantity and arrangement of its constituents.

They may be based on a number of simplifying assumptions, and

their use in design should tempered with extreme caution!

RULES OF MIXTURE AND ELASTIC PROPERTIES

DENSITY

0

50 0

100 0

150 0

20 00

2500

300 0

0 0 ,2 0 ,4 0 ,6 0 ,8 1

KG

/M

3

FIBRE VOLUME FRA CTION

RULE OF MIXTURES DENSITY FOR GLASS/EPOXY COMPOSITES

rf

rm

GENERALISED RULE OF MIXTURES FOR TENSILE MODULUS

is a length correction factor ( 1 for fibres longer than about 10 mm)

corrects for non-unidirectional reinforcement:

UNIDIRECIONAL 1.000

BIAXIAL 0/90 0.500

BIAXIAL 45/-45 0.250

RANDOM 0.375

0

10

20

30

40

50

60

0 ,0 00 00 1 0 ,0 5 0 ,1 0 ,15 0 ,2 0 ,25 0 ,3 0 ,35 0 ,4 0 ,45 0 ,5 0 ,55 0 ,6 0 ,65 0 ,7 0 ,75

TE

NS

ILE

MO

DU

LU

S (

GP

A)


UD BIAXIAL CSM

RULE OF MIXTURES TENSILE MODULUS

(GLASS FIBRE/POLYESTER)

0

20

40

60

80

100

120

140

160

180

20 0

0 ,0 00 00 1 0 ,1 0 ,2 0 ,3 0 ,4 0 ,5 0 ,6 0 ,7

TE

NS

ILE

MO

DU

LU

S (

GP

A)


UD BIA XIA L QUA SI-ISOTROPIC

RULE OF MIXTURES TENSILE MODULUS

(T300 CARBON FIBRE)

0

20

40

60

80

100

120

140

160

180

0 ,15 0 ,2 0 ,25 0 ,3 0 ,35 0 ,4 0 ,45 0 ,5 0 ,55 0 ,6 0 ,65 0 ,7

GP

a


UD BIA XIA L UD QUA SI-ISOTROPIC UD PLA IN W OVEN

RULE OF MIXTURES ELASTIC MODULUS

HS CARBON / EPOXY RESIN

UT TENSIO, SIC VIS THE EXTENSION IS PROPORTIONAL TO … · fiberglass 7.000 1 e 06 fiberglass...

Documents

Transcript of UT TENSIO, SIC VIS THE EXTENSION IS PROPORTIONAL TO … · fiberglass 7.000 1 e 06 fiberglass...