background and aims. the aim of this study was to assess the opening torque of grooved and non-grooved screws made of shape memory alloys (sma) for fixation of mandibular fractures. materials and methods. in this in vitro study the opening torques of ten sma screws with grooves and ten sma screws without grooves were compared in 20 holes (10 holes for grooved screws and 10 holes for non-grooved...

in this research a cu-zn-al alloy is produced by melting the raw materials in an electric resistance furnace and then pouring it into a steel mould. the optimum way to achieve the final analysis in the hypo-eutectoid range is determined and the influence of the alloying element, ti on the grain size and the shape memory properties of the samples are investigated. solution treatment (done at 850...

A thermomechanical model for shape memory alloy (SMA) actuators and SMA hybrid composite (SMAHC) structures has been recently implemented in the commercial finite element codes MSC.Nastran and ABAQUS. The model may be easily implemented in any code that has the capability for analysis of laminated composite structures with temperature dependent material properties. The model is also relatively ...

A unique shape memory alloy (SMA) restrainer cable is developed and tested to evaluate its effectiveness in limiting the hinge opening in bridges. The SMA cables, connected at the deck–abutment interface, are tested on a four-span, one-quarter scale, concrete slab bridge. The bridge is subjected to a suite of ground motion to assess the performance of the SMAs under different magnitudes of load...

Abstract Shape memory alloy (SMA) materials possess complete superelasticity or pseudoelasticity above the austenite finish temperature (Af) and many unique mechanical, thermal, thermal–mechanical and electrical properties compared with other conventional materials. Many studies have reported that the superelastic and hysteresis properties of SMA materials can absorb energies coming from extern...

As a rst step towards the design of a high frequency, high force, large strain shape memory alloy(SMA) actuator, we model in this work a thermoelectrically cooled thin SMA layer linear actuator. The SMA is subjected to cyclic phase transition between the martensitic and austenitic phases by alternate heating/cooling, achieved with the thermoelectric Peltier e ect of a pair of P/N semiconductors...

The shape memory alloy (SMA)-based robotic hand has been a new emerging technology with potential applications ranging from life service to surgical treatment, because of the characteristics SMA, such as high power-to-weight ratio, small volume and low driving voltage. However, due complex dynamic model nonlinear aspects it is complicated control an SMA-based hand. This paper presents novel fre...

A large scale testing program was conducted to determine the effects of shape memory alloy (SMA) restrainer cables on the seismic performance of in-span hinges of a representative multiple-frame concrete box girder bridge subjected to earthquake excitations. Another objective of the study was to compare the performance of SMA restrainers to that of traditional steel restrainers as restraining d...

A kind of shape memory alloy (SMA) hysteretic nonlinear model is developed, and the stochastic bifurcation characteristics of SMA intravascular stents subjected to radial and axial excitations are studied in this paper. A new nonlinear differential item is introduced to interpret the hysteretic phenomena of SMA strain-stress curves, and the dynamic model of SMA intravascular stent subjected to ...

Abstract Soft composite actuators can be fabricated by embedding shape memory alloy (SMA) wires into soft polymer matrices. Shape retention and recovery of these are typically achieved incorporating segments the actuator structure. However, this requires complex manufacturing processes. This work uses multimaterial 3D printing to fabricate with variable stiffness capable recovery. The hinges be...