Development of amorphous and nanocrystalline Al65Cu35−xZrx alloys by mechanical alloying

Mechanical alloying of Al65Cu35−xZrx (x=5, 15 and 25 at.% Zr) elemental powder blends by planetary ball milling up to 50 h yields amorphous and/or nanocrystalline products. Microstructure of the milled product at different stages of milling has been characterized by X-ray diffraction, (XRD) high-resolution transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). Among the different alloys synthesized by mechanical alloying, Al65Cu20Zr15 yields a predominantly amorphous product, while the other two alloys develop a composite microstructure comprising nanocrystalline and amorphous solid solutions in Al65Cu10Zr25 and nano-intermetallic phase/compound in Al65Cu30Zr5, respectively. The genesis of solid-state amorphization in Al65Cu20Zr15 and Al65Cu10Zr25 is investigated.