A review of recent advancements in the impact response of fiber metal laminates

Abstract

Fiber metal laminates (FMLs) have garnered significant attention due to their exceptional impact resistance, making them attractive for various structural applications. This review presents recent advancements in understanding the impact behavior of FMLs under low- and high-velocity impact scenarios. Low-velocity impacts, commonly encountered during manufacturing, handling, and tool drops, are discussed, with a focus on damage mechanisms, energy absorption capabilities, and influential factors such as impactor geometry and boundary conditions. Additionally, this review delves into high-velocity impact events, simulating scenarios such as ballistic impacts, highlighting the role of FMLs in mitigating perforation and enhancing damage tolerance. The effects of various parameters on the impact response are critically analyzed. The findings presented herein contribute to the development of lightweight, impact-resistant FML components for aerospace, automotive, and defence applications.

Keywords: Composites; Fiber metal laminates (FMLs); High-velocity impact (HVI); Impact response; Low-velocity impact (LVI).

Fig. 1

FML classification.

Fig. 2

Classification of impact loading based on impact velocity.

Fig. 3

a)Force Displacement Curves FML at 60 J, and 75 J, b) Failures on top and bottom surface layers, c) Sectional View of failed FML [13]. (Reproduced with permission from Elsevier License Number – 5604030015245).

Fig. 4

Comparison of modified and unmodified SEM images of failed FMLs: (a) cross-sectional area and (b) and (c) magnified images of the damaged section [18]. (Reproduced with permission from Elsevier License Number – 5604021275085).

Fig. 5

A) Stress‒strain plot from the tensile test, B) cross-sectional view of the failed FML, and C) force‒time and energy–time curves for FML 2/2 at various impact energies(a-d) and the corresponding back side of the specimen [21]. (Reproduced with permission from Elsevier License Number – 5581750432209).

Fig. 6

A) Force‒time for the a)HBFM, b) H2024-T3, B) Force‒time for the a)OBFM, b)O2024-T3, C) force‒displacement curves for the a)HBFM and b)OBFM [23]. (Reproduced with permission from Elsevier License Number – 5604000802610).

Fig. 7

A) Cross-sectional images of failed samples of different FMLs. B) comparison of the AFE and AFB hybrid FMLs a) Force‒time, b) deflection‒time, c) force displacement, and d) work-time curves [25]. (Reproduced with permission from Elsevier License Number – 5604010270016).

Fig. 8

Specimen configurations based on placing the elastomer, (A) the elastomer up (EU), (B) the elastomer down (ED), and (C) without the elastomer (WE), and (D) comparison of sample cross-sections from experimental tests and numerical simulations [26].

Fig. 9

Damages and failures on the top, bottom, and cross-sectional views of FML laminates under different impactor heads A) Flat impactor, B) Hemispherical impactor, C) Conical impactor [45]. (Reproduced with permission from Elsevier License Number – 5604010520142).

Fig. 10

Factors influencing the High-Velocity Impact Behavior of FML Composites.

Fig. 11

High-velocity impact testing setup: a) gas gun system, b) high-speed camera, and c) projectile [70]. (Reproduced with permission from John Wiley and Sons License Number – 5581341121679).

Fig. 12

Stacking configuration of the FML sample [82].

Fig. 13

A) Damage induced in the FML impacted at various incident velocities. B) Impact pictures of a high-speed camera of a projectile on GLARE 5 FML [85] (Reproduced with permission from Elsevier License Number - 5604011394966).

Fig. 14

Stacking sequence order of the aluminum plate inside the laminated (a) upper, (b) middle and (c) lower layers. (Reproduced with permission from Elsevier License Number – 5641990456580).

Fig. 15

Cross-sectional images of failed FML sandwich laminates: a) UD and b) Woven composite [91]. (Reproduced with permission from Elsevier License Number – 5604020984546).

Fig. 16

a) Various nose head projectiles, b) GFRP laminates for high-velocity impact, and c) clamping target plates [92]. (Reproduced with permission from Elsevier License Number – 5604010767619).

Fig. 17

Vicinity of damage morphology of composite layers and metal sheets in FML: a) CFRP and b) HB50 [101]. (Reproduced with permission from Elsevier License Number – 5604020425483).

Fig. 18

Pieces of the perforated FML structure. SPB: shear plugging block, FPO: fiber pull-out [102]. (Reproduced with permission from Elsevier License Number – 5604020683674).