A Theoretical Investigation on Low Velocity Impact on Composite Plates Reinforced with Shape Memory Alloy Wires Including Damage Evolution

Investigating of composite laminates strengthened with shape memory alloy (SMA) thin films, as new smart structures, which has higher impact resistance in comparison with conventional fiber-reinforced polymer (FRP) laminates, is a new subject that researchers have studied these kind of laminates both analytically and experimentally. In the present article, the behavior of a laminated graphite-epoxy strengthened with shape memory alloy thin films, under impact load, is modeled. Also deformation of the laminate as well as development of damage, caused by low velocity impact, is investigated. For this purpose, a two degree of freedom spring-mass system is used to estimate the contact load between laminated plate and the impactor. The stiffness of the plate changes over time and after damage initiation, the composite plate is divided into two undamaged and damaged regions. Each region has its own specific stiffness that changes over time. Through using theory of first-order shear deformation (FSDT), deflection of the plate, stress and strain fields are calculated. The effect of embedding SMA wires, with different volume fractions, on the contact load, deflection of the plate, stress and strain fields are studied with considering damage evolution. Results show that by using SMA wires into composite plate, maximum deflection of the plate, stresses and strains reduce and the strength of the laminated plate against impact loading increases. © 2021, The Institution of Engineers (India).