BACKGROUND To realize atraumatic vessel occlusion, a new hemostatic clamp using superelastic shape memory alloy (SMA) as a pressure control limiter has been proposed. It was designed taking advantage of a unique mechanical property of SMA. The ability to control pressure with the newly designed SMA clamp was investigated. The traumatic effect on vessel walls was evaluated in order to confirm th...

Living cells are constantly subjected to various mechanical stimulations. They must sense the mechanical aspects of their environment and respond appropriately for proper cell function. In general, cells adhere to substrata. Thus, the cells must receive and respond to mechanical stimuli mainly from the substrata. For example, migrating cells can create their own polarity and migrate in a certai...

Shape memory alloy (SMA) wires can be embedded in a host material to alter the stiffness or modal response and provide vibration control. The interaction between the embedded SMA and the host material is critical to applications requiring transfer of loads or strain from the wire to the host. Although there has been a significant amount of research dedicated to characterizing and modeling the r...

The properties and cost have made the Nickel-Titanium (NiTi) shape memory alloys (SMA) attractive for a variety of applications wherein shape memory effect (SME) / superelasticity (SE) and biocompatibility are important. Anisotropy of the shape recovery associated with shape memory effect strongly depends on the type of r 30 minutes in air) Ti-Rich Ni-Ti SMA (Ni51at%Ti) when subjected to cold r...

In this study, the combined effects of strengthening, precipitates, and textures on the shape recovery ability and superelasticity of thermomechanically treated Ti49.3Ni50.7 shape memory alloy (SMA) in both the rolling and transverse directions were studied by experimental measurements and theoretical calculations. Experimental results and theoretical calculations showed that the 300 °C × 100 h...

Hysteretic dynamical systems are challenging to control due to their hard nonlinearity and difficulty in modeling. One type of systemwith hysteretic dynamics that is gaining use in aerospace systems is the shape-memory alloy-based actuator. These actuators provide aircraft and spacecraft systems with the ability to achieve component-level or vehicle-level geometry or shape changes. Characteriza...

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Previous work at NASA Langley Research Center (LaRC) involved fabrication and testing of composite beams with embedded, pre-strained shape memory alloy (SMA) ribbons within the beam structures. That study also provided comparison of experimental results with numerical predictions from a research code making use of a new thermoelastic model for shape memory alloy hybrid composite (SMAHC) structu...

Benign prostatic hyperplasia (BPH) remains an incompletely understood disease, mostly striking old men. In fact, 40% of men over 50 show evidence of BPH [1]. The main consequence of BPH is an uncontrolled growth of prostate epithelial and stromal tissues. Eventually, this may lead to an acute urinary retention (AUR) [2], calling for an emergency treatment. Today, the first line treatment consis...

This report introduces Shape Memory Alloys, describes properties of SMA as an actuator and introduces some available commercial SMA actuator products.