Mechanical behavior of nanostructured TiNi shape memory alloy with different grain size. (2017)

• Record Type: Journal Article
• Authors: Resnina, Natalia; Belyaev, Sergey; Pilugin, Vitali; Glazova, Diana
• Is Part Of: Materials today. Volume 4:Number 3(2017)Part B
• Page Start: 4841
• Page End: 4845
• Publication Date: 2017
• Subjects: Grain size -- TiNi -- Mechanical properties -- Hall-Petch law -- Deformation mechanisms; Materials science -- Congresses -- Periodicals; 620.1
• DOI: 10.1016/j.matpr.2017.04.081
• Languages: English
• ISSNs: 2214-7853

Abstract

Abstract: The influence of grain size on the deformation mechanisms of nanostructured Ti-50, 2at.%Ni alloy during tension at two temperatures was studied. The deformation temperatures were chosen as 130 °C, at which TiNi phase was in the B2 phase; and 25 °C, at which the TiNi phase was in the R and/or B19' phase depending on the grain size. The results showed that in the austenite B2 phase, the nanostructured TiNi alloy was unelastically deformed by dislocation slip and no pseudoelasticity behavior was observed. At a temperature of 25 °C, the reorientation of martensite crystals was found before the dislocation slip, as observed for coarse-grained TiNi alloy. The deformation mechanisms observed in the nanostructured Ti-50, 2at.%Ni alloy were the same as those in the coarse-grain and a decrease in grain size did not have any additional effect on the mechanical behavior of the samples. It was found that in the samples of the Ti-50, 2at.%Ni alloy with a grain size of 80 nm and less, the dependence of the yield stress on grain size was described by the Hall-Petch law.