Chapter 16: Composites

Example 16.1 Page No 589

In [15]:
E_gf=69.0     # in GPa  Elasticity of glass fibre
mf_gf=0.4     #Vol % of glass fibre
E_pr=3.4      # in GPa  Elasticity of poyester resin
mf_pr=0.6     #Vol % of polyester resin

E_cl=(E_pr*mf_pr)+(E_gf*mf_gf)
Ac=250.0         #mm**2
sigma=50.0       #MPa
ratio=(E_gf*mf_gf)/(E_pr*mf_pr)    # ratio=Ff/Fm
Fc=Ac*sigma    #N
Fm=Fc/(ratio+1)
Ff=Fc-Fm
Am=mf_pr*Ac
Af=mf_gf*Ac
sigma_m=Fm/Am
sigma_f=Ff/Af
e_m=sigma_m/(E_pr*10**3)  #Strain for matrix phase
e_f=sigma_f/(E_gf*10**3)  #Strain for fiber phase

print"(a)Modulus of elasticity of composite is ",round(E_cl,0),"GPa"
print"(b)Load carried by each of fiber and matrix phase is ",round(Ff,0),"N"
print"(c)Strain for matrix phase is ",round(e_m,4)
print"   Strain for fiber phase is ",round(e_f,4)

(a)Modulus of elasticity of composite is  30.0 GPa
(b)Load carried by each of fiber and matrix phase is  11640.0 N
(c)Strain for matrix phase is  0.0017
   Strain for fiber phase is  0.0017

Example 16.2 Page No 591

In [7]:
E_gf=69      # in GPa  Elasticity of glass fibre
mf_gf=0.4    #Vol % of glass fibre
E_pr=3.4     # in GPa  Elasticity of poyester resin
mf_pr=0.6    #Vol % of polyester resin

E_ct=E_pr*E_gf/((E_pr*mf_gf)+(E_gf*mf_pr))  #GPa

print"In transverse direction, modulus of elaticity is ",round(E_ct,1),"GPa"

In transverse direction, modulus of elaticity is  5.5 GPa

Design Example 16.1 ,Page No :601

In [10]:
Do=70*10**-3        #mm, outside diameter
Di=50*10**-3        #mm, inside diameter
L=1                 #m Length
F=1000              #N load
dy=0.35*10**-3      #mm, deflection

E=(4*F*L**3)/(3*math.pi*dy*(Do**4-Di**4))
Vc=(math.pi*L*(Do**2-Di**2))/4.0

print"(a)longitudinal modulus of elasticity is",round(E/10**9,1),"GPa"
print"(b)The total tube volume is",round(Vc*10**6,0),"cm**3"

(a)longitudinal modulus of elasticity is 68.3 GPa
(b)The total tube volume is 1885.0 cm**3
In [ ]: