In the present article, the dynamic behavior of sandwich plates with embedded shape memory alloy (SMA) wires is evaluated for two cases wherein (i) the stress-strain curve of the superelastic behavior of the SMA wires is symmetric and (ii) the mentioned curve is non-symmetric. A modified version of Brinson’s constitutive model is proposed and used. The high non-linearity in the behavior stems f...

-A nonlinear finite element procedure is developed which incorporates a thermodynami~ly derived cons~tutive law for shape. memory alloy material behavior. The constitutive equations include the necessary internal variables to account for the material transfo~ations and are utilized in a onedimensional finite element procedure that captures the unique shape memory alloy responses of pseudoelasti...

*Correspondence: Marcelo J. Dapino, 201 West 19th Avenue, Columbus, OH 43210, USA e-mail: [email protected] Shape memory composites (SMCs) based on shape memory alloys (SMAs) and shape memory polymers (SMPs) allow many design possibilities due to their controllable temperature-dependent mechanical properties. The complementary characteristics of SMAs and SMPs can be utilized in systems with shap...

The response of shape memory alloy (SMA) components employed as actuators has enabled a number of adaptable aero-structural solutions. However, there are currently no industry or government-accepted standardized test methods for SMA materials when used as actuators and their transition to commercialization and production has been hindered. This brief fast track communication introduces to the c...

We have investigated the effect of pressure and thermal ageing on transformation behavior of Ni-%45.16Ti shape memory alloy. 70-320 MPa pressure was applied and annealed at 500 o C for 2 hour to see the effect of applied pressure on transformation temperature. It was observed that the starting and final temperature of austenit increased, the martensite start temperature almost remain constant a...

A combined theoretical/experimental study of the heat transfer in thermoelectric Shape Memory Alloy (SMA) actuators is undertaken in this paper. A one-dimensional model of a thermoelectric unit cell with a SMA junction is developed rst and the transient temperatures in the SMA are evaluated for di erent applied electric current densities. As a rst step towards the design of an actuator, a therm...

Mechanical counter-pressure (MCP) space suits, which apply pressure to the wearer using tight-fitting materials rather than pressurized gas, offer numerous mobility and mass advantages over traditional gas-pressurized suits [1]. However, MCP design challenges related to pressure uniformity, pressure magnitude, and donning/doffing remain unsolved [2]. Previous MCP efforts have focused on passive...

Underactive bladder or detrusor underactivity (DU) is defined as a reduction of contraction strength or duration of the bladder wall. Despite the serious healthcare implications of DU, there are limited solutions for affected individuals. A flexible 3D printed implantable device driven by shape memory alloys (SMA) actuators is presented here for the first time to physically contract the bladder...

A gripping device actuated by shape memory alloy (SMA) wire was fabricated and investigated. The actuation mechanism and the working rinciple of the gripping device are simple. A SMA wire was used to close the gripper during operation and a torsion spring was integrated to open he gripper when the SMA wire relaxed. Several experiments were conducted to investigate the performance of the grippin...

The recovery stress of martensitic shape-memory alloy [SMA] wires can be used to confine concrete, and the confining effectiveness of the SMA wires was previously proved through experimental tests. However, the behavior of SMA wires under recovery stress has not been seriously investigated. Thus, this study conducted a series of tests of NiTiNb martensitic SMA wires under recovery stress with v...