Fiber and Laminar Composites

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FIBER AND LAMINAR

COMPOSITES



FIBERS



COMPOSITE MATERIALS

• Composite materials have two or morephysically and chemically faces on amicroscopic scale separated by a distinct

interface• In composites! the constit"ent which

present in lar#er $"antities are termed as“Matrix”.

• The constit"ents which present in smaller$"antities as compared to matri% aretermed as ”Reinforcement”.



REI&'ORCEME&T

• The p"rpose of addin# thereinforcement is to #et the desirableproperties of matri%

• Types of reinforcements "sed incomposites are (

)* 'ibers

+* ,his-ers

.* 'la-es

/* Partic"lates



'I0ERS

• 'ibers are similar to the thread which are "sed

as principle load resistin# members incomposite

materials• 'ibers are #enerally "sed as reinforcement in the

composite materials to prevent the penetration

of the crac-



T1PES O' 'I0ER2based on reinforcement*

'I0ER REI&'ORCE3COMPOSITES

Sin#le layered M"ltilayered

LaminatesSandwich 4ybrid

panels

Contin"o"s 5bers 3iscontin"o"s 5bers

6ni 7 directional 0i7 directional Random Ali#ned

orientation

orientation



CLASSI'ICATIO& O' 'I0ERS

20ased on materials*

Classi5cation of 5bers based on thematerials

"sed for the 5bers(

)* 8lass 5bers

+* Carbon 5bers

.* Aramide 5bers /* 0oron 5bers

9* Ceramic 5bers



8LASS 'I0ERS

• 8lass 5bers are the most common ofall reinforcin# 5bers for polymericcomposites2PMC:s*

• The types of #lass 5bers "sed in the5ber reinforced plastics 2'RP:s * are (

)* E7 #lass

+* S7 #lass .* C7 #lass



GLASS FIBER



E-GLASS:

• E7#lass has the lowest cost of allcommercially available reinforcin#5bers! which is the reason for itswidespread "se in 'RP in the

ind"stryAPPLICATIOS:

• E7#lass 5bers mainly "sed where the

electrical ins"lations are re$"ired



S-GLASS:

• S7#lass has the hi#hest tensile stren#th

amon# all the #lass 5bers

• 4owever! the compositional di;erenceand hi#her man"fact"rin# cost ma-e it

more e%pense than E7#lass APPLICATIOS:

• S7#lass mainly "sed for the aircraft

components and missile casin#s



C-GLASS:

• C7#lass has better chemical propertiesthan E7#lass and S7#lass

APPLICATIOS:

• C7#lass are "sed where thereresistance is re$"ired a#ainst acid andcorrosion



CAR0O& 'I0ERS

• Carbon 5bers are commercially available with

a variety of tensile mod"l"s val"es ran#in#

from

+<= 8pa2.<%)<>? psi* on the low side to )<.98pa 2)9<%)<?? psi*

• In #eneral! the low7mod"l"s 5bers have the

lower density! lower cost! hi#her tensile andthe

compressive stren#ths



• Carbon is very li#ht element with thedensity of ++?@ # cc

• 8enerally amon# crystalline forms ofCarbon #raphite str"ct"re is "sed ascomposites

• In the carbon! the atoms are

arran#ed in the form of he%a#onallayers



CAR0O& 'I0ERS

©2003 Brooks/Co le, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark sed herein nder license.



APPLICATIOS:

• 4i#h temperat"re applications li-espace and air crafts

• Electrical and thermal cond"ctin#applications

• Aerospace and sportin# #ood

Ind"stries



ARAMI3E 'I0ERS

• Aramide 5bers are prod"ced from thechemical

called Aromatic and Polyamide and so itcalled

as the Aramide 5bers

• It is a man"fact"re 5ber in which 5berformin#

s"bstance is a lon# chain syntheticpolyamide in

which at least @9B of amide lin-a es or



• Commercial names of Aramide 5bers are as

EDELAR and &ome%

• O"t of these EDELAR is "sed for thereinforcement

in r"bbers

!E"ELAR-#$:

• EDELAR7+ is "sed for ropes!cables! coatedand architeched fabrics

!E"ELAR-%$ :

•It is mainly "sed for reinforcement of the Epo%ypolyesters and other resins for "se in theAerospace machine ! A"tomative and Sportsind"stry



0ORO& 'I0ER

• 0oron is coated on a s"bstance which is called

as s"bstrate "s"ally made of t"n#sten

• 0oron is deposited on t"n#sten and the

processis contin"ed "ntil the desired thic-ness of 5ber

obtained

• Properties of the boron 5bers #enerally

chan#es

with the diameter of the t"n#sten



PROPERTIES

• 3ensity of boron is +./ #cc

• 0oron 5ber with t"n#sten core has adensity

of +? #cc for a 5ber )<<"m

• Meltin# point is +</<o Celsi"s

•

Thermal e%pansion co7eFcient of@.%)<>7?

"p to .)9 de#ree Celsi"s



CERAMIC 'I0ERS

The ceramic 5bers for notable hi#hertemperat"re

applications are(

)* Silicon Carbide

+* Al"min"m o%ide



SILICO& CAR0I3E 'I0ER

• Silicon carbide can be created over fewmetals and their room temperat"re! tensilestren#th and tensile mod"le are li-e those of

boron and t"n#sten• Elevated temperat"re properties are #ood

• They show only .9B loss of stren#th

• Silicon carbide coated on t"n#sten or Siliconcarbide coated on carbon ! both have veryhi#h

•

Stress at ))<<o

C and ).<<o

C



AL6MI&A 'I0ERS

• Al"mina 5bers are commonly employed inmetal matrices

• Ma#nesi"m and Al"min"m matrices "seAl"min"m 5bers reinforced composites as theydo not dama#e the 5ber even in the li$"idstate

• It o;ers #ood compressive stren#th rather

than tensile stren#th• It has hi#h meltin# point of abo"t +<<<o C



LAMIAR COMPOSITES



LAMI&AR COMPOSITES

• Laminar composites involves two or more Layersof the same or the di;erent materials

• The layers can be arran#ed in di;erent directions

to #ive the stren#th where needed• Li-e all composites laminar composites aim at

combinin# the constit"ents to prod"ce properties

neither constit"ents alone wo"ld have

In laminar composites there are t o



• In laminar composites there are twoimportant

terms they are(

)* 'ace

+* 0ase

'ACE(

• The face in laminar composites are o"termetal which is similar to that of the matri%in the

Composites0ASE(

• The inner metal of the laminar composites

are called as base



LAMI&ATE3 STR6CT6RE



LAMI&A

LAMI&A(• A lamina is a Gat 2or some times

c"rved*arran#ement of "nidirectional or

woven 5bers in a s"spended in a matri%material

• The thic-ness of lamina depends "pon the

material from which it made• 'or the p"rpose of analysis! a lamina is

typically modeled as havin# one layer of5bers thro"#h the thic-ness



STR6CT6RE O' LAMI&A



LAMI&ATE

LAMI&ATE(• A laminate is a stac-in# of lamina!

where oriented in a speci5c manner to

achieve the desired res"lt • Individ"al lamina is bonded to#ether by

a c"rin# proced"re that depends on the

material "sed• The mechanical response of a laminate is

di;erent from that of individ"al lamina

that forms the laminate



The laminate:s propertiesdepends "pon the

properties of each lamina! as well as orderin which

the lamina are stac-ed



STR6CT6RE O' A LAMI&ATE



T1PES O' LAMI&ATES

'ew special type oflaminates and the

standard lamination code are as #iven asfollows(

)* 6nidirectional laminate

+* An#le7ply laminate

.* Cross7ply laminate

/* Systematic laminate



6&I3IRECTIO&AL LAMI&ATE

6&I3IRECTIO&AL LAMI&ATE(

• In a "nidirectional laminate! the 5berorientation an#les are the same in alllaminas

• 'or e%amples! in a "nidirectional laminatethe orientation in a lamina is <o then the

orientation in all laminates are <o



6&I3IRECTIO&AL LAMI&ATE



A&8LE PL1 LAMI&ATE

• In an an#le7ply laminate! if the orientationof a

lamina is < then the orientation of secondlaminate is

7<

• In other words the alternate layersorientation

of the an#le7ply laminate is opposite in thesi#n



CROSS7PL1 LAMI&ATE

• In cross7ply laminate the 5ber orientationan#les in alternate layers are <o and <o

• The orientation of each laminate in thecross Hply laminate described as follows(

)* <o

+* <o

.* <o

/* <o



CROSS7PL1 LAMI&ATE



S1MMETRIC LAMI&ATE

In a symmetric laminate! the ply7orientation

is symmetric abo"t the centerline of thelaminate

that is ! for each ply above the mid plane! there is

an identical ply at an e$"al distancebelow the mid

plane



T4A& 1O6

Fiber and Laminar Composites

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