A process was developed for fabricating arrays of micro-channels in shape-memory NiTi for bone implant applications, with a tailorable internal architecture expected to improve biomechanical compatibility and osseointegration. Ni-51.4 at.% Ti with 24-34 vol.% porosity was fabricated by electrochemical dissolution of parallel layers of steel wire meshes embedded within a NiTi matrix during hot p...

Transformation sequences in a NiTi shape memory alloy after deformation and subsequent annealing were studied using various methods. Low temperature annealing of the deformed alloy caused that the R-phase preceeded the martensitic transformation. The R-phase formation during both cooling and heating depends strongly on the deformation degree and temperature of annealing. On DTA curves an additi...

Abstract The large reversible strain upon heating (shape memory effect) or unloading (superelasticity), high power-to-weight ratio, good functional stability, compact size, and lightweight make the rotary NiTi shape alloys actuators an interesting candidate for various engineering applications. Additive manufacturing (AM) provides a single step freeform process that not only fabricates complex ...

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...

Laser microwelding was used to join, for the first time, superelastic NiTi biomedical PtIr which can be in multicomponent devices. By process optimization, it possible control formation of B2 NiTiPt phase, with no intermetallic compounds being formed. The phase inside fusion zone had a strong metallurgical bonding base material due smooth transition its grain orientation towards ?111? NiTi. maj...

The shape memory effect (SME) response of a deformation-processed NiTiNb shape memory alloy is benchmarked against the response of a cast alloy. The insoluble Nb element ternary addition is known to widen the hysteresis with respect to the binary NiTi alloy. Cast microstructures naturally consist of a cellular arrangement of characteristic eutectic microconstituents surrounding primary matrix r...

The effect of Ni-content on phase transformation behavior of NiTi-20 at. % Zr high temperature shape memory alloy (HTSMA) is investigated over a small composition range, i.e., 49.8, 50.0 and 50.2 at. % Ni, by differential scanning calorimetry (DSC), high-energy synchrotron radiation X-ray diffraction (SR-XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). All s...