Shape Memory Alloy Wire Reinforced Composites for Structural Damage Repairs

Abstract

Shape memory alloys (SMA) have demonstrated their potential use in various smart structural applications. SMA undergo a reversible phase transformation from martensite to austenite as temperature increases. This transformation leads to shape recovery and to the associated recovery strains.SMA can also be used to enhance the capacity of a damaged structure, especially adhesively bonded joints. One approach is to use SMA-reinforced patches for enhancing adhesively bonded joints. To this end a design strategy, by which one can integrate the properties of SMA reinforcement to improve the interlaminar stresses of the bonded joint must be developed. Therefore, an analytical solution for evaluation of the stresses in a SMA wire reinforced composite patch used for repairing cracks in banded joints was created. The variables considered in the model are the fraction of SMA wires, the associated phase transformation strain, patch thickness, and adhesive layer's thickness and mechanical properties. A finite element analysis (FEA) was also conducted to verify the integrity of the results obtained through the proposed solution, and good agreement was obtained.

Applications of Nickel-Titanium Alloy

“…In recent times, reinforcement and repair of the damaged structure using SMAs is to be introduced in civil engineering [58][59][60][61][62][63][64][65][66]. Files and Olson [67] might be founders in crack healing SMA, followed by many others (e.g., [58,68,69]).…”

Fabrication of NiTi alloy: A review

“…Reinforcement and repair of damaged civil structure using SMAs has been introduced in civil engineering. [10][11][12][13][14][15][16][17][18][19][20] NiTi is used in civil structures, because of its high density, energy dissipation through hysteresis, corrosion resistance, shape recovery after large strain and high fatigue resistance high stress. But still design guidelines are in a pending state to use SMA as seismic protective system.…”

Bending theory for laminated composite cantilever beams with multiple embedded shape memory alloy layers

“…Models for SMAs have been proposed by numerous research groups (Boyd and Lagoudas, 1996;Brinson, 1993;Chemisky et al, 2011;Liang and Rogers, 1990;Saint-Sulpice et al, 2012;Zaki and Moumni, 2007), and innovative applications using SMA technology were developed for aerospace (Jani et al, 2014), automotive engineering (Butera et al, 2007), robotics (Fujita, 1989), biomedical solutions (Machado and Savi, 2003), and so on. In particular, SMA-reinforced composite materials were proposed for applications in shape adaptation and control (Otsuka and Wayman, 1998), enhancement of resistance to buckling (Birman, 1997), structural frequency adjustment (Chen and Levy, 1999;Ostachowicz et al, 2000), damage repair (Shahin et al, 2005), vibration control (Fuller et al, 1996;Rogers et al, 1989), deflection and stress reductions under low-velocity impact (Birman et al, 1996), sensing, and absorption of impact energy (Angioni et al, 2011).…”