Effect of Ce addition on the glass-forming ability and thermal stability of Sm-Cu-Ni-Al alloys

Sm55-xCexCu15Ni10Al20 (x=0,7,10,13,15,20,25) alloy samples were prepared by casting the melt ingots into a water-cooled copper mould under vacuum. The structure of the alloy samples were analyzed with X-ray diffraction. The glass transition, crystallization and melting behavior of the alloys were investigated by differential scanning calorimetry (DSC). The supercooled liquid region Delta T-x and the reduced crystallization temperature T-x/T-m were used to indicate the glass-forming ability. T-g and T-x were used to indicate the thermal stability. As a result, with the addition of Ce the thermal stability of Sm-based were decreased and with a certain amount of Ce it has the best glass-forming ability which can prepare bulk metallic glasses samples of phi 5 mm or more. The glass-forming ability of this system were discussed based on electronegativity difference Delta X and Miedema's theory.