Damping characteristics of Ti50Ni47Fe3 alloy

Low-frequency internal friction (IF) of Ti50Ni47Fe3 alloy has been measured in the temperature range of 100-400 K, as well as the electrical resistivity and differential scanning calorimetry (DSC). Similar to other TiNi-based alloys IF of the austenitic phase (B2) is very low and almost independent of temperature, while it increases steeply at B2-R phase transformation. Then, making a sharp peak, IF decreases with decreasing temperature gradually. The peak height is around 50 x 10(-3), indicating a very large damping capacity of 27%. At the A, temperature, which appears around 100 K, IF makes a small peak associated with the phase transition. Temperature dependence of electrical resistivity and calorimetric measurement show that a two-stage phase transformation takes place, which is in accordance with the behavior of IF. It has been revealed that the M-s temperature is dependent on the solution treatment temperature. (C) 2007 Elsevier B.V. All rights reserved.