No Cover Image

Journal article 651 views 195 downloads

Valence Electron Ratio for Design of Shape Memory Alloys with Desired Phase Transformation Temperatures

Mehrdad Zarinejad, Kiyo Wada, Farshid Pahlevani, Reza Katal, Sajjad Rimaz

Shape Memory and Superelasticity, Volume: 7, Issue: 1, Pages: 179 - 189

Swansea University Author: Kiyo Wada

Check full text

DOI (Published version): 10.1007/s40830-021-00319-0

Abstract

Dependence of phase transformation temperatures of TiPd- and TiPt-based shape memory alloys on valence electron ratio (VER), number (ev/a), and average atomic number of the alloys (Z) are investigated. The alloys have medium numbers of valence electrons (6.6 ≤ ev/a ≤ 7.3) that are near 7 and a wide...

Full description

Published in: Shape Memory and Superelasticity
ISSN: 2199-384X 2199-3858
Published: Springer Science and Business Media LLC 2021
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa56691
Abstract: Dependence of phase transformation temperatures of TiPd- and TiPt-based shape memory alloys on valence electron ratio (VER), number (ev/a), and average atomic number of the alloys (Z) are investigated. The alloys have medium numbers of valence electrons (6.6 ≤ ev/a ≤ 7.3) that are near 7 and a wide range of the average atomic number (Z = 25–54). The forward and reverse phase transformation temperatures, Ms and (As), increase with average atomic number of the alloys, respectively. Clear correlations between transformation temperatures and VER are found. Ms and (As) both decrease from around 1184 °C (1175 °C) to as low as 20 °C (32 °C), respectively, with increasing VER from 0.134 to 0.270. Temperature hysteresis of the thermoelastic transformation in these alloys tends to decrease with increasing VER. Dependence of transformation temperatures and temperature hysteresis of these shape memory alloys on VER is discussed based on the variations of elastic moduli and atomic bonding due to composition change.
Keywords: phase transformation temperature, valence electron, shape memory alloy, TiPd, Ti Pt, intermetallics
College: Faculty of Science and Engineering
Issue: 1
Start Page: 179
End Page: 189

Similar Items