Answer:
632.5 MPa
Explanation:
[tex]\sigma_{m}[/tex] = Matrix stress at fiber failure = 10 MPa
[tex]V_f[/tex] = Volume fraction of fiber = 0.25
[tex]\sigma_f[/tex] = Fiber fracture strength = 2.5 GPa
The longitudinal strength of a composite is given by
[tex]\sigma_{cl}=\sigma_{m}(1-V_f)+\sigma_fV_f\\\Rightarrow \sigma_{cl}=10(1-0.25)+(2.5\times 10^3)\times 0.25\\\Rightarrow \sigma_{cl}=632.5\ MPa[/tex]
The longitudinal strength of the aligned carbon fiber-epoxy matrix composite is 632.5 MPa
