Comparative study of two types of self-recovery shape-memory alloy pseudo-rubber isolator devices under compression–shear interactions

Abstract

Two types of novel shape-memory alloy-based devices with three-dimensional isolation potential and deformation recovery abilities were developed. These two types of isolators, which are called shape-memory alloy pseudo-rubber isolators, were both created with martensitic shape-memory alloy wires through weaving, rolling, and punching processes, but they underwent heat treatment at different fabrication stages and for different durations. A series of mechanical tests were performed on these two types of shape-memory alloy pseudo-rubber isolators to investigate their properties under compression, shear, and combined compression–shear loading at room temperature. The restorable shear limit was then investigated, and the corresponding shear failure mechanism was discussed according to a tension test of one thin layer of the shape-memory alloy wire mesh. Subsequently, the deformation recovery ability of the shape-memory alloy pseudo-rubber isolator with residual deformation was tested through heating on a thermo-control stove. Finally, the mechanical-property stabilities, energy-dissipation abilities, and recovery abilities were compared between the two types of shape-memory alloy pseudo-rubber isolator devices. The experimental results indicated that both types of shape-memory alloy pseudo-rubber isolators had excellent residual deformation recovery abilities, and the type-I shape-memory alloy pseudo-rubber isolator device had more stable mechanical properties than the type-II shape-memory alloy pseudo-rubber isolator. The type-I shape-memory alloy pseudo-rubber isolator device is thus an ideal candidate for traditional three-dimensional isolators.

Softening Effects in Biological Tissues and NiTi Knitwear during Cyclic Loading

“…Considering that during the cyclic tension of the knitted NiTi mesh there was a variable residual strain and stress hysteresis, depending on the wire diameter, it can be assumed that the losses were associated with friction at the contact areas during slipping of the loops. It is known that the Mullins effect is characteristic of tensegrity structures [ 48 ], rubber-like materials [ 49 ], cell membranes [ 50 ], and pressed shape-memory wires [ 51 ]. Comparing the stress-strain curves of a 60 μm wire and a knitted mesh created from it, it is clear that the tensegrity structure of the knitted mesh limited the manifestation of the superelastic effect inherent in the wire.…”

Laser powder bed fusion of diatom frustule inspired bionic NiTi lattice structures: compressive behavior and shape memory effect

“…In addition, using NiTi in satellite solar cell arrays, spacecraft antennas, and rotary actuators of active helicopter rotor blades had been experimentally and theoretically researched [7,8]. However, due to the relatively simple structure [9,10], the existing NiTi components cannot meet the high-performance and multi-functional needs of the aerospace field. Therefore, the structure of NiTi components should be preciously designed to realize controllable performance [4,11].…”