Effect of projectile nose on high-velocity impact behavior of fiber metal laminates

Fiber metal laminates (FMLs) are a class of hybrid materials consisting of several thin metal layers bonded by layers of composite material. In the present study, the ballistic limit, absorbed energy, specific perforation energy and failure mechanism of FML 2/1 (Al/GFRE/Al) and FML 3/2 (Al/GFRE/Al/GFRE/Al) are numerically and experimentally studied under the high-velocity impact loading using a single-stage light gas gun. In addition, the ballistic behavior of FML 2/1 and FML 3/2 is investigated using three different projectile nose geometries. Numerical simulation of the ballistic tests was performed to determine the residual velocity and the FML panel failure mechanism by using AUTODYN. The results indicated that the highest ballistic limit for FML 2/1 and FML 3/2 was obtained for the conical nosed projectile and the ballistic limit of FML 3/2 was 75.63% higher than FML 2/1. Although the FML 3/2 thickness is similar to 67% higher than FML 2/1, the specific perforation energy of FML 3/2 is improved by 72.51%, 55.26%, and 89.22% compared to FML 2/1 for blunt, hemispherical, and conical nosed projectiles, respectively.