In this study, NiTi thin films were deposited on the glass and NaCl substrates by means of magnetron sputtering method. The influence of aging temperature, over the range 300-500 oC, on phase transformation and mechanical properties of the sputtered NiTi thin films were studied by differential scanning calorimetry (DSC) and nano-indentation assay, respectively. The DSC curves showed that the ag...

We report on free-standing NiTi alloy nanowires (120 nm × 75 nm) fabricated using a technique referred to as "nanoskiving", which complements conventional thin film sputter deposition with ultramicrotomy for thin sectioning. To date, the technique has been limited to pure metals without exploring metallic alloys. Leveraging the technique for the fabrication of shape memory alloy (SMA) nanostruc...

We have investigated the crystallization of amorphous equiatomic NiTi thin films sandwiched between two protective silicon nitride barrier films using optical, atomic force, and transmission electron microscopy. Crystallite nucleation occurs homogeneously inside the NiTi films because small composition shifts at the interfaces between NiTi and surrounding layers suppress heterogeneous nucleatio...

Nanocrystalline TiN/NiTi thin films have been grown on silicon substrate by dc magnetron sputtering to improve the corrosion and mechanical properties of NiTi based shape memory alloys without sacrificing the phase transformation effect. Interestingly, the preferential orientation of the TiN films was observed to change from (1 1 1) to (2 0 0) with change in nature of sputtering gas from 70% Ar...

The mechanical properties of sputter-deposited NiTi shape memory alloy thin films ranging in thickness from 35 nm to 10 μm were examined using nanoindentation and atomic force microscopy (AFM). Indents made in films as thin as 150 nm showed partial shape recovery upon heating, although film thickness was found to have a marked effect on the results. A modified spherical cavity model is used to ...

The temperature dependence of the crystallite nucleation and growth rates is measured for amorphous NiTi thin films. Using transmission electron microscopy, crystallites are shown to nucleate homogeneously in the film and to grow in a channeling mode. A mechanism that suppresses heterogeneous nucleation is proposed. By manipulating nucleation and growth rates, grains as large as 60 lm can be ob...

Surface nanomechanical behavior under nanoindentation of ZrN and ZrCN film on NiTi substrate was studied. The surface hardness and modulus of the films increase initially with larger nanoindentation depths and then reach their maximum values. Afterwards, they diminish gradually and finally reaching plateau values which are the composite modulus and composite hardness derived from the ZrN/ZrCN f...

Nanocantilevers have become key components of nanomechanical sensors that exploit changes in their resonant frequencies or static deflection in response to the environment. It is necessary that they can operate at a given, but adjustable, resonant frequency and/or static deflection ranges. Here we propose a new class of nanocantilevers with a significantly tunable spectrum of the resonant frequ...

Laser annealing of shape memory alloy thin films provides new opportunities in actuator design and fabrication for microelectromechanical systems applications. In this paper, we present a three-dimensional thermal model to simulate the crystallization process when a laser beam is swept across an amorphous NiTi thin film. Experimental crystallite nucleation and growth rates are included in the m...