Effects of external static electrical field on thermal and electrical conductivity in the Al-Cu, Al-Ni, and Al-Si eutectic alloys

Abstract

This study aims to investigate the effects of external positive and negative static electric fields (E₊ and E_- respectively) on thermal conductivity (K) and electrical conductivity (σ) in Al-33 wt. % Cu, Al-6.4 wt. % Ni and Al-12 wt. % Si eutectic alloys. For this purpose, the solidifications of Al-Cu, Al-Ni, and Al-Si eutectic alloys were directionally done under E₊ and E_-. The directions of E were chosen to be parallel (E₊) and antiparallel (E_-) to the solid-liquid (S-L) growth direction and the magnitudes of E were approximately (+10) and (−10) kV cm⁻¹ and (+16) and (-16) kV cm⁻¹ for the Al-Cu, Al-Ni, and Al-Si eutectic alloys, respectively. The effects of E₊ and E₋ on the K and σ were determined by the longitudinal heat flow and the four-point probe methods, respectively. While the K and σ values decreased with increasing temperature, the K and σ were increased and decreased with E₊ and E₋, respectively.