High temperature internal friction in Ni50.3Ti29.7Zr20 shape memory alloy

• Published in: Intermetallics Vol. 109; pp. 174 - 178
• Main Authors: Zuo, Shungui, Wu, Riming, Pang, Guobo, Yang, Yanping, Jin, Mingjiang
• Format: Journal Article
• Language: English
• Published: Barking Elsevier Ltd 01.06.2019; Elsevier BV
• Subjects: Activation; Binary alloys; Enthalpy; Heat resistant alloys; High temperature; Internal friction; Martensitic transformation; Ni[sbnd]Ti[sbnd]Zr; Precipitation; Shape memory alloy; Shape memory alloys; Zener relaxation; Zirconium; NiTiZr; Martensitic transformation; Precipitation; Internal friction; Shape memory alloy
• ISSN: 0966-9795; 1879-0216
• DOI: 10.1016/j.intermet.2019.04.006

The internal friction at temperature up to 980 K in Ni50.3Ti29.7Zr20 (at.%) high temperature shape memory alloy was investigated. A relaxation peak was observed at about 750 K for 0.1 Hz. Its activation parameters were determined, Hact = 1.82 ± 0.04 eV, τ0 = 2.22 × 10−12 s. Similar relaxation peak with the activation enthalpy of about Hact = 1.42 eV was observed in NiTi binary alloy at a slightly lower temperature. Alloying of Zr is found to increase the activation enthalpy of this relaxation. The mechanism of this relaxation was discussed based on a Zener relaxation related to the short-range diffusion of Ni. [Display omitted] •A relaxation peak at approximately 750 K for 0.1 Hz is observed in Ni50.3Ti29.7Zr20 alloy.•The activation parameters of the peak is determined as Hact = 1.82 ± 0.04 eV, τ0 = 2.22 × 10−12 s.•Similar relaxation peak was observed in NiTi binary alloy.•Alloying of Zr increased the activation enthalpy of the relaxation.