Question

Question 1. A continuous and aligned fibre-reinforced composite material is to be produced consisting of 40 vol % glass fibres and 60 vol % of an epoxy matrix. The mechanical characteristics of these two materials are as follows: MaterialModulus of Elasticity rcture Strength (GPa) (MPa) 2500 Glass Fibre 76 Epoxy 3.35 58 For this composite material, estimate by calculation the following parameters: i. The longitudinal tensile strength ii. The longitudinal modulus of elasticity

Answer 1

Ans ) Given,

Volume of glass fiber(V_f) = 40%

   Volume of epoxy matrix (V_m) = 60%

i) Longitudinal Tensile strength of composite material($\dpi{100} \sigma$_c) :

$\dpi{100} \sigma$_c = $\dpi{100} \sigma$ _fV_f + $\dpi{100} \sigma$ _m V_m

= 2500(0.40) + 58(0.60)

= 1034.8 MPa

ii) Longitudinal modulus of elasticity of composite material (E_c)

E_c = E_fV_f + E_mV_m

= 76(0.40) + 3.35(0.60)

= 32.41 GPa