Ballistic Impact Behaviour of Glass/Epoxy Composite Laminates Embedded with Shape Memory Alloy (SMA) Wires

Abstract

This paper aims to estimate the enhancement in the energy absorption characteristics of the glass fiber reinforced composites (GFRP) by embedding prestrained pseudo-elastic shape memory alloy (SMA) that was used as a secondary reinforcement. The pseudo-elastic SMA (PE-SMA) embedded were in the form of wires and have an equiatomic composition (i.e., 50%–50%) of nickel (Ni) and titanium (Ti). These specimens are fabricated using a vacuum-assisted resin infusion process. The estimation is done for the GFRP and SMA/GFRP specimens at four different impact velocities (65, 75, 85, and 103 m/s) using a gas-gun impact set-up. At all different impact velocities, the failure modes change as we switch from GFRP to SMA/GFRP specimen. In the SMA/GFRP specimen, the failure mode changed from delamination in the primary region to SMA-pull out and SMA deformation. This leads to an increase in the ballistic limit. It is observed that energy absorbed by SMA/GFRP specimens is higher than the GFRP specimens subjected to the same levels of impact energy. To understand the damping capabilities of SMA embedment, vibration signals are captured, and the damping ratio is calculated. SMA dampens the vibrations imparted by the projectile to the specimen. The damping ratio of the SMA/GFRP specimens is higher than the GFRP specimens. The damping effect is more prominent below the ballistic limit when the projectile got rebounded (65 m/s).

Shape Memory Hybrid Composites

“… 30 An improvement in energy absorption capacity of CFRP composites was found at 10 J of impact energy that is attributed to the stress-induced martensitic transformation (SIM), reversible deformation, and hysteretic energy dissipation of the superelastic wires. The impact and vibration damping ability of SMA-reinforced glass fiber composites (GFRPs) was studied by Verma et al 88 The energy absorption and vibration damping capacity of the SMA/GFRP composite are found to be better than unreinforced GFRP composites. The vibration damping ratio of SMA/GFRP is better below the ballistic limit, i.e., 65 m/s, above which SMA fiber pullout is observed, resulting in a decrease in damping capacity.…”

Effect of Graphene Oxide-Boron Nitride-Based Dual Fillers on Mechanical Behavior of Epoxy/Glass Fiber Composites

“…Conversely, the stiffness of epoxy resin primarily depends on the existence of crosslinking density. Still, the occurrence of higher crosslink density might lead to the formation of brittle fracture with minor deformations [3,4].…”