Thermal conductivity and electrical resistivity dependences on growth rate in the directionally solidified Al-Cu-Ni eutectic alloy

Abstract

The thermal conductivity and electrical resistivity dependences on growth rate in the directionally solidified Al-Cu-.Ni eutectic alloy (Al-32.5 wt%Cu-%l wt.Ni) were investigated. For this purpose, the Al-Cu.Ni eutectic alloy was solidified at a constant temperature gradient of 4.93 K mm(-1) with different growth rates, V = 9.25-2056.68 mu m s(-1) by a Bridgman type directional solidification furnace. The thermal conductivity (K) and electrical resistivity (rho) of the Al-Cu-Ni alloy solidified with different growth rates were measured with the longitudinal heat flow method and DC four-point probe technique at room temperature. The dependences of K and rho on V for directionally solidified Al-Cu-Ni eutectic alloy were experimentally obtained by linear regression analysis. Finally, the specific heat difference between solid and liquid phases (Delta C-P) and enthalpy of fusion (Delta H) for Al-32.5 wt%Cu-%l wt.Ni alloy were determined by means of differential scanning calorimetry (DSC) at its melting temperature. (C) 2018 Elsevier B.V. All rights reserved.