Effect of Graphene Nanoplatelets on Progressive Failure Behavior under Internal Pressure of Composite Cylindrical Pressure Vessels

In this study, burst behavior of filament winding basalt/epoxy composite cylindrical pressure vessels (B-CPVs) with 0.25 wt.% graphene nanoplatelets (GnPs) reinforced and non-reinforced [±55°]4 configurations was investigated for close-ended conditions. An innovative test apparatus was designed to obtain close-ended conditions. Internal pressure tests of the GnPs reinforced and non-reinforced B-CPVs were carried out following ASTM D1599 standard. Radial and axial displacements of reinforced and non-reinforced CPVs under the internal pressure were detected using linear position sensors. Elasticity moduli of reinforced and non-reinforced B-CPVs were determined for pressurized conditions. Burst failure pressure of the non-reinforced samples was found to be increased by 13.34%. The GnPs reinforcement increased the amount of strain that occurs in the radial and axial directions of non-reinforced B-CPVs. After the burst testing, formation and progression of damage under internal pressure were evaluated based on the measured data and microscopic analysis. Consequently, it was found that damage formation such as matrix cracking, transverse cracks, debonding, and leakage can occur for the investigated conditions. Besides, the mechanical performance improvement of non-reinforced B-CPVs under internal pressure was achieved due to homogeneous distribution of GnPs in the epoxy matrix and strengthening adhesion of the fiber-matrix interface. Graphical Abstract: [Figure not available: see fulltext.]