NOMENCLATURE
a Crack length
a * The shortest distance between the midpoint of two cracks
B Thickness of FMLs
W Width of sample
\(K_{I}\) Stress intensity factor of mode I
\(K_{\text{II}}\) Stress intensity factor of mode II
\(K_{C}\) Critical value of stress intensity factor of mixed mode
\(K_{I}^{0}\) The revised results of stress intensity factor of mode I
\(K_{\text{II}}^{0}\) The revised results of stress intensity factor of
mode II
\(K_{e}\) Effective revised stress intensity factor range
θ Inclined angles