Effects of geometry on the impact response of curved composite laminates with concave and convex curvature

Abstract

Laminated composite structures with curved geometries are widely used in various engineering applications due to their lightweight and high-strength properties, but their behavior under low-velocity impact remains a critical area of study. This research experimentally investigates the impact response of curved laminated composites with concave and convex curvatures. Test specimens were designed with three distinct camber heights, and a custom fixture was utilized to conduct impact tests at two initial energy levels, with three repetitions per condition to ensure measurement accuracy. Results indicate that concave specimens exhibit significantly smaller damaged areas compared to convex ones under similar impact energies. Furthermore, increasing camber height leads to a larger damaged area. While delamination and matrix cracking dominate the damage mechanisms across all samples, no fiber breakage is observed in concave specimens. To provide further insights, the study evaluates maximum impact force, maximum displacement, and surface damage using optical imaging of the front and back sides of the specimens. These findings contribute to a deeper understanding of the impact performance of curved composites, informing their design and application in impact-prone environments. Highlights: Experimental analysis of curved composite laminates with low-velocity impact. Optical imaging of front and back surfaces of curvature damage propagation. Identifies distinct failure mechanisms: delamination and matrix cracking. Reveals a correlation between increased camber height and damage zones. © 2025 Society of Plastics Engineers.