Balancing impact and indentation performance of hybrid GFRE-steel mesh laminates under various indenter shapes and loading scenarios

The study offers insight into the behavior of hybrid composites under both low-velocity and sudden impact conditions through the evaluation of quasi-static indentation (QSI) and Izod impact. QSI tests are utilized for evaluating energy absorption, damage initiation, and load capacity under various indenter shapes (Hemispherical, conical and flat). For evaluating surface and through-thickness impact performance, Izod impact tests utilize flat and edge-wise loading conditions. The study examines hybrid laminates comprising GFRE laminates and expanded steel mesh of varied sizes and arrangements, fabricated utilizing the hand layup process. Failure mechanisms and damage area are recognized and evaluated utilizing a digital microscope and image processing techniques. Results showed that indenter shape affected loading and failure behavior: the flat indenter yielded high load and energy, conical caused lower load with extended penetration, and the hemispherical provided progressive loading response. Mesh size and arrangement had a significant effect on performance. Fine mesh enhanced energy absorption and peak load by up to 27.5 % and 20.5 %, respectively, while coarse mesh showed moderate performance. Medium mesh exerted the lowest damage area with reduction of −32.8 %. Outer arrangement showed limited damage, while inner arrangement improved initial stiffness and impact toughness by up to 11.9 %. The study offers a strategy for optimizing hybrid variables to enhance mechanical reliability under various impact conditions, which can be utilized for practical applications in aerospace, automotive, and defense structures.