Loss of pseudoelasticity in nickel-titanium sub-micron compression pillars

摘要: Abstract Nickel–titanium (NiTi) is capable of undergoing pseudoelastic deformation wherein relatively large amounts inelastic are recovered upon load removal due to a martensitic phase transformation. This study investigates as well plastic in sub-micron diameter NiTi compression pillars. Pillars ranging from approximately 2 μm 200 nm were prepared using focused ion beam micro-machining aged [1 1 1] single crystal NiTi. Results reveal pseudoelasticity all samples tested with diameters between and 400 nm, although permanent strain was introduced at low strains compared bulk. Decreased sample size generally showed smaller stress–strain hysteresis, full loss recoverable for than 200 nm. In addition, flow stress the martensite shown be independent material. Lastly, it observed that crystallographic orientation has stronger influence on strength pillar size.