Quantification of Sensitization in AA5083-H131 via Imaging Ga-Embrittled Fracture Surfaces

Sensitization of 5xxx series Al alloys involving precipitation of beta phase (Mg2Al3) at grain boundaries was studied for different exposure times at 100 degrees C upon AA5083-H131 (UNS A95083). In this work, we reveal that fracture surfaces prepared by liquid gallium embrittlement can yield a quantification of grain boundary beta phase with significant statistics on beta phase size and spacing. This information is a necessary first step toward development of quantitative damage models to describe intergranular corrosion (IGC) and stress corrosion (IGSCC).