INTRODUCTION This article aims to evaluate how different superelastic nickel-titanium (NiTi) alloys determine the static mechanical performance of endodontic files during bending and torsion. METHODS Two NiTi rotary instruments with similar geometries and equal cross sections, ProFile GT (GT) and a GT Series X (GTX), were selected. The latter file is made from M-Wire, a NiTi alloy that, accor...

Based on the experimental results and the finite element analysis, a constitutive model is proposed for two phase shape memory alloys by introducing a compensative volumetric strain into a constrained relationship between the two phases, accounting for the reduced constraint due to the growth of martensite band. The pseudoelasticity of NiTi shape memory alloy micro-tube, subjected to pure tensi...

It is well known that the Fe based alloys can exhibit shape memory effect due to the y to E martensitic transformation. The effect may not be as striking as observed in the NiTi alloy but it might become attractive fkom the practical point of view. In this work, two compositions of Fe-Cr-Ni-Mn-Si(-Co) stainless steel based shape memory alloy, prepared by the VIM technique, will be presented. Th...

This study investigated the deformation effects of the interface between conventionally produced stainless steel X2crNi 19 11 and HIPed NiTI coating (Hot Isostatic Pressed). Near-equiatomic nickel-titanium alloy (NiTi) has many attractive material properties, such as pseudo-elasticity and shape memory effects, which result into beneficial engineering properties e.g. as cavitation resistant coat...

Traditionally, prosthetic limb is interconnected to the residual limb via a “socket”. As the body weight upon the prosthesis is transferred through soft tissue to human skeleton, the muscles and skin could be traumatized. To overcome the problem, an osseointegration trans-femoral implant technique has been used to attach prosthetic limb to human skeleton directly. However, due to the malfunctio...

Large changes in hysteresis are reported as a function of applied stress under thermal cycling experiments in NiTi single crystals. In the low Ni alloy the thermal hysteresis expanded with increasing stress while in the high Ni alloy the thermal hysteresis contracted with increasing stress. The results in both cases meet the limit obtained from Differential Scanning Calorimetry at zero stress. ...

The development of innovative adaptive structures on UAVs (and UUVs), such as morphing wings, can potentially reduce system complexity by eliminating control surfaces and their auxiliary equipment. This technology has the potential of allowing a UAV to adapt to different mission requirements or executing a particular mission more effectively. The first part of the paper deals with a review of m...

T his is the fourth paper in our series, identifying unusual phenomena and providing recommendations for the thermo-mechanical characterization of shape memory alloy (SMA) wire. Part 11 provided basic background of the martensitic transformations between austenite (A) and martensite (M) which are responsible for the shape memory (SM) effect and superelasticity (SE). Two typical NiTi SMA alloys ...

A new membrane actuator based on our previous diaphragm actuator was designed and constructed to improve the dynamic performance. The finite element analysis was used to estimate the frequency response of the composite membrane which will be driven close to its resonance to obtain a large stroke. The membrane is made of ferromagnetic shape memory alloy (FSMA) composite including a ferromagnetic...