2005 Volume 46 Issue 12 Pages 2880-2885
Although pre-crystallization phase separation was reported in the Al88Gd6Er2Ni4 amorphous alloy, this work has found no evidence for it. Surface crystallization was found to occur prior to the major crystallization of α-Al nanocrystals, which caused uneven foil thickness in transmission electron microscopy (TEM) specimens prepared by electro-polishing, resulting in artificial phase separation like contrast in TEM image. Partially crystallized samples were composed of α-Al nanocrystals with little solute content and an amorphous matrix. No solute enrichment was found at the interface between α-Al and the amorphous matrix, which acts as the heterogeneous nucleation sites for further formation of α-Al crystal, resulting in interconnected nanograin microstructure.
