Mechanical and ballistic studies of boron carbide filler reinforced glass fiber composites

Abstract Owing to the outstanding properties of boron carbide (B 4 C) particles, material researchers have shown potential in filler‐reinforced polymer composites. The present work studied the implication of B 4 C fillers on the mechanical and ballistic properties of glass fiber epoxy reinforced composites. Two different weight percentages of 2 and 4 wt% B 4 C fillers were used to modify the epoxy resin. The composite samples with glass fabric woven were made through compression molding. The results show that the tensile, flexural, interlaminar, impact strength and hardness of glass fiber composite were improved by addition of 2 wt% of B 4 C. The high‐velocity ballistic tests were conducted on the unfilled and B 4 C filler‐reinforced composites using a 9 mm parabellum projectile with an initial striking of 372 ± 15 m/s. The least back face signature (BFS) and highest specific energy absorption (SEA) were observed for 2 wt% B 4 C filler composite. Adding B 4 C filler enhanced matrix toughening and interfacial bonding between fiber and matrix. Matrix cracking and fiber breakage result in the least ballistic resistance for unfilled composite. Fracture behavior was studied on tensile, impact, and ballistic‐tested samples using scanning electron microscopy. The fractured surfaces of filler‐reinforced composite demonstrated good interfacial bonding, matrix hardening, and fiber pullouts. Highlights The addition of B 4 C with epoxy up to 2 wt% improves the mechanical and ballistic properties of the composites. The least back face signature and highest specific energy absorption were observed for 2 wt% B 4 C filler composite. B 4 C filler enhanced matrix toughening and interfacial bonding between fiber and matrix. Failure of unfilled glass fiber composites is a combination of matrix cracking, fiber pullout, and interface debonding.