Observation of a metastable Cu phase formed at a crystalline Si/liquid Al-alloy interface in Al-Cu-Mg-Si alloy

Abstract

This study employed in-situ high-resolution transmission electron microscopy (HRTEM) to quantify the structure of a metastable Cu phase that was found to form at the interface between solid Si and liquid Al-alloy in an Al-Si-Cu-Mg alloy at 650 °C. HRTEM image simulations were used to determine the structure of the interface and the {113}Si||{076}Cu; <110>Si||<100>Cu orientation relationship (OR) between the solid phases. Atom-row matching showed that 44% of the Si atom-rows aligned with Cu atoms in this OR.