Microstructural evolution and growth behavior of intermetallic compounds at the liquid Al/solid Fe interface by synchrotron X-ray radiography

Abstract

The growth of Inter-Metallic Compounds (IMCs) with dissolution was investigated on the liquid Al/solid Fe interconnection by using synchrotron radiation real-time imaging technology. At the initial stage of holding at 850°C, a layer of the η-Fe2Al5 phase formed at the interface, and tongue-like η grew into α-Fe. The tongue-like η phase had a stronger (001) texture than the layered phase. The coalescence of tongue-like η started at the bottom, followed by the dissolution of IMCs, which leads to a further increase in its growth rate. During solidification stage, the dotted, needle-like and flake θ-FeAl3 phases were sequentially formed.