Rasit Zengin

Influence of neutron irradiation on the characteristics of Cu–13%wt.Al–4%wt.Ni shape memory alloy

Abstract Unirradiated and neutron irradiated Cu–13%wt.Al–4%wt.Ni shape memory alloy, SMA, were investigated by differential scanning calorimetry, DSC, and electrical resistivity changes, ERC, measurements, X-ray diffraction, XRD and optical microscopy methods. The forward and reverse temperatures of martensite⇔austenite phase transformation decreased and transformation enthalpies increased after the neutron irradiation of samples. Some changes in the lattice parameters and surface morphologies of sample were also seen after neutron irradiation.

Effects of hydrostatic pressure on the martensitic phase transformation, thermal conduction and thermodynamic parameters of Cu–13 wt.% Al–4 wt.% Ni shape memory alloy

Effects of hydrostatic pressure on the martensitic phase transformation, thermal conduction and thermodynamic parameters of Cu-13 wt.% Al-4 wt.% Ni alloy have been investigated. The pressure dependence of Ms, Mf, As and Af temperatures are interpreted in the frame of the study. The pressure dependence of the dissipative energy terms of the martensitic and reverse transformation has been separated and analyzed. It is found that the transformation temperatures of the shape memory alloy increase with applied stress. The thermal conductivity of the alloy was measured as a function of pressure. The thermodynamic parameters such as enthalpies, entropy and specific heat capacity of the alloy were determined. D 2003 Elsevier Science B.V. All rights reserved.