Phase transformation and deformation behavior of NiTi-Nb eutectic joined NiTi wires

• DOI: 10.1038/srep23905
• Publication Date: 2016-04-06T09:09:55Z
• Authors: Liqiang Wang; Cong Wang; Lai-Chang Zhang; Liangyu Chen; Weijie Lu; Di Zhang
• Keywords: Nickel titanium; Eutectic bonding; Diffusionless transformation; R-Phase

NiTi wires were brazed together via eutectic reaction between and Nb powder deposited at the wire contact region. Phase transformation deformation behavior of NiTi-Nb microstructure investigated using transmission electron microscopy (TEM) cyclic loading-unloading tests. Results show that R phase B19' martensite are induced by plastic deformation. transformation, which significantly contributes to superelasticity, preferentially occurs interfaces Round-shaped Nb-rich with rod-like lamellar-type eutectics observed in regions. These phases appear affect region five distinct stages stress-strain curves: (I) reorientation, (II) from parent phase, (III) elastic reoriented accompanied lamellar eutectic, (IV) martensitic (V) specimen.