Electrical resistivity of Ti-Ni binary and Ti-Ni-X (X = Fe, Cu) ternary shape memory alloys
Journal
Materials Science and Engineering A
Journal Volume
438-440
Journal Issue
SPEC. ISS.
Pages
536-539
Date Issued
2006
Author(s)
Abstract
The electrical resistivities of Ti-Ni binary and Ti-Ni-X (X = Fe, Cu) ternary shape memory alloys (SMAs) are investigated. Experimental results reveal that the Ti-Ni and Ti-Ni-X SMAs exhibit different electrical resistivity (ρ) characteristics due to their different martensitic transformation behaviors. The increase of ρ during the B2 → R transformation of Ti-Ni SMAs is about 10-16 μΩ cm, which is a change of about 12-20%. For a two-stage transformation of B2 ↔ R ↔ B19′, there is a sharp increase of ρ during B2 → R transformation, and then a rapid decrease of ρ during R → B19′ transformation. However, for the Ti-40 at.%,Ni-10 at.%,Cu alloy, which exhibits a B2 ↔ B19 ↔ B19′ two-stage transformation, there is a small variation of ρ during B2 → B19 transformation, but a significant variation of ρ during B19 → B19′ transformation. These phenomena may be ascribed to their different structures, deformation defects, accommodated twin variants and crystal distortions. © 2006 Elsevier B.V. All rights reserved.
Type
journal article