Thermodynamic behavior of NiTi shape memory alloy against low-velocity impact: experiment and simulation

The response of laminated hybrid composite beam with embedded shape memory alloy wires subjected to impact of multiple masses is analytically investigated. Two degree of freedom spring-mass system and Fourier series are used in order to study the low velocity impact phenomenon on the resulting hybrid composite beam. A linearized contact law is chosen to calculate the contact force history. The effect of pseudo elasticity of wires as well as the recovery stresses generated in shape memory alloy wires due to shape memory effect is investigated. The beam is subjected to impactors with various masses, radii, and initial velocities. Impacts are occurred on the top and/or bottom surface of the beam. The effects of volume fraction of shape memory alloy wires, location of embedded wires, location of impacts and pre-strain in shape memory alloy wires on the contact force history and the deflection curve of the beam are investigated. The obtained results illustrated that embedding shape memory alloy wires in the laminated composite beam caused the deflection of the beam to occur more local at the points of impact, in comparison with the beams without shape memory alloy wires. Moreover, embedding 0.2 volume fraction of the shape memory alloy wires reduced the maximum deflection of the beam subjected to impact of 2 impactor masses by 57% and 3 impactor masses (on both sides) by 12%. Pre-straining the wires caused more reduction in deflection of the beam under impact loading.

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The low-velocity impact and compression after impact (CAI) behavior of foam core sandwich panels with shape memory alloy hybrid face-sheets

Science and Engineering of Composite Materials ◽

10.1515/secm-2019-0034 ◽

2019 ◽

Vol 26 (1) ◽

pp. 517-530 ◽

Cited By ~ 2

Author(s):

Ye Wu ◽

Yun Wan

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Sandwich Panels ◽

Image Correlation ◽

Low Velocity Impact ◽

Foam Core ◽

Low Velocity ◽

Velocity Impact ◽

Compression After Impact ◽

The Impact

AbstractDue to the properties of shape memory effect and super-elasticity, shape memory alloy (SMA) is added into glass fiber reinforced polymer (GFRP) face-sheets of foam core sandwich panels to improve the impact resistence performance by many researchers. This paper tries to discuss the failure mechanism of sandwich panels with GF/ epoxy face-sheets embedded with SMA wires and conventional 304 SS wire nets under low-velocity impact and compression after impact (CAI) tests. The histories of contact force, absorbed energy and deflection during the impact process are obtained by experiment. Besides, the failure modes of sandwich panels with different ply modes are compared by visual inspection and scanning electron microscopy (SEM). CAI tests are conducted with the help of digital image correlation (DIC) technology. Based on the results, the sandwich panels embedded with SMA wires can absorb more impact energy, and show relatively excellent CAI performance. This is because the SMA wires can absorb and transmit the energy to the outer region of GFRP face-sheet due to the super-elasticity-behavior. The failure process and mechanism of the CAI test is also discussed.

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