Comparison of the dynamic characteristics of GFRP, CFRP, and hybrid composites subjected to repeated low-velocity impact

Abstract

The current study used the vacuum-assisted hand lay-up method (VAHLM) to manufacture glass fiber-reinforced polymer (GFRP), carbon fiber-reinforced polymer (CFRP), and glass/carbon fiber-reinforced hybrid composites to examine the influences of fiber materials and hybridization on the repeated low-velocity impact (LVI) responses. In this regard, the manufactured composites were exposed to repeated LVI loading at 3 m/s under 25.2 J impact energy, and thus dynamic characteristics such as total impulse, contact/bending stiffness, interaction time, peak force/displacement, and absorbed-rebounded energies depending on the impact number were acquired. LVI tests were continued until penetration was observed in the composites, at which point the penetration threshold numbers for each composite type were acquired. Furthermore, the macro-scale damage analyses depending on the impact number were gradually examined, and the impacts of hybridization and fiber material on the damage mechanisms were determined. The study found that GFRP, hybrid and CFRP composites had the highest impact resistance, respectively, and that glass fiber-reinforcement is well-suited for applications that require higher impact resistance. When the average penetration threshold numbers for the composites were examined, it was observed that GFRP composites had approximately five times higher penetration threshold numbers than CFRP composites and that hybrid specimens exhibited similar properties to CFRP composites in terms of impact resistance. This scenario was linked to the various deformation capabilities of glass and carbon fibers, and it was concluded that the high-deformation capability of the fibers improved the penetration threshold numbers.