Dynamic Fracture Toughness and Damage Monitoring in Hybrid Composites

An experimental investigation is performed to study dynamic mode-I fracture toughness and damage sensing capabilities of hybrid composites using a novel modified split-Hopkinson pressure bar (SHPB) setup. Six different hybrid glass/carbon composites (two interlaminar and four intralaminar) are considered in this study. A modified four probes measurement system and high-speed imaging are used to determine the change in resistance response and dynamic fracture toughness. Furthermore, scanning electron microscopy (SEM) imaging is used to investigate the fracture mechanisms. Mode-I fracture toughness is also determined under static loading conditions to compare with that of dynamic conditions. Results show that G-inter interlaminar composite shows the highest fracture initiation toughness (G(IC)) of 741 J/m(2) and 620 J/m(2) under dynamic and static loading conditions, respectively. However, (G45/C45)(A) intralaminar composite shows better damage sensing capability with a change in resistance of 1168% and 593% for a 40 mm crack growth under dynamic and static loading conditions, respectively. The composites also demonstrate rate sensitivity for both fracture initiation toughness and the peak resistance change during mode-I fracture loading.

Automated summary

This study investigates the dynamic mode-I fracture toughness and damage sensing capabilities of hybrid composites using a modified split-Hopkinson pressure bar (SHPB) setup. Six different hybrid glass/carbon composites are considered, and a four probes measurement system and high-speed imaging are used to determine resistance response and fracture toughness. Scanning electron microscopy (SEM) imaging is used to investigate fracture mechanisms. The results show that different composites have varying fracture initiation toughness and damage sensing capabilities under different loading conditions.