PSI - Issue 18

D.A. Bondarchuk et al. / Procedia Structural Integrity 18 (2019) 353–367 D.A. Bondarchuk, B.N.Fedulov, A.N. Fedorenko/ Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 6. Ratio of maximum(minimum) stress in composite before cut to stress after cut.

The bar chart diagram (Fig. 7) and Fig. 4 show that absolute maximum stress in a transverse direction (σ y ), mainly concentrated in a quite small area, and close to the ultimate stress of composite material provided in epoxy matrix product datasheet (2018). Thus there is a possibility of nucleation of microcracks in sample during manufacturing or at low exploitation load, which confirms the conjecture about the reduction of mechanical performance, especially for matrix-dominated loading. The results of the simulation are consistent with the conclusions indicated by Zobeiry et al. (2016), who demonstrated the initiation of matrix cracks in [0 0 /90 0 ] composite sample as a result of residual stresses obtained during curing cycle.