Segregation and clustering of solutes at grain boundaries in Mg–rare earth solid solutions

The present study validates the previously reported investigations about segregation of rare-earth (RE) elements at grain boundaries in Mg–RE alloys and ultimately provides a direct visualization of the distribution of the solute atoms in the structure of a Mg–Gd alloy. It is demonstrated that Gd forms a solid solution within the Mg matrix in addition to substantial segregation at high-angle grain boundaries in the form of 1–2 nm clusters, with...