Eur. Phys. J. Plus (2020) 135: 765
https://doi.org/10.1140/epjp/s13360-020-00737-6

Regular Article

Phase transformation temperatures and physical characteristics of NiTiCo shape memory alloys produced by arc melting method

Faculty of Science, Department of Physics, Firat University, Elazig, Turkey

^a ctatar@firat.edu.tr

Received: 14 April 2020
Accepted: 31 August 2020
Published online: 26 September 2020

Abstract

The effect of cobalt addition with different proportions into Ni_50−xTi₅₀Co_x and 6 wt%) shape memory alloys was investigated. The alloys were produced by arc melting method and then some characteristics, including microstructure, phase transformation temperatures, and magnetic properties, were analyzed. Additionally, the determination of the crystal structure on the alloy’s microstructural phases, changes in chemical composition proportions, phase transformation temperatures, and magnetization were investigated at room temperature using XRD, SEM–EDX, DSC, and PPMS, respectively. As a consequence of these measurements, the absorbed and released energies and transformation temperatures exhibit an obvious decrease with the increase of Co addition into the alloys. The microhardness results revealed that the second phase of the alloys has higher hardness compared to the matrix phase. Moreover, with the increase of Co addition into the alloy, Gibbs free energy showed a regular increase while elastic energy exhibited irregular changes. The increase of Co addition to the alloys increased the magnetization property of the alloys.