Glass Forming and Crystallization of Melt-Spun Mg65(Cu1-xAlx)25MM10 (MM: Mischmetal) Alloys

S. ROZENBERG, F. AUDEBERT, C. RODRIGUEZ ALIAGA, C. BOLFARINI, C.S. KIMINAMI AND W. J. BOTTA F

Rio de Janiero, Brasil

Workshop; III Workshop on Metastable and Nanostructured Materials” (NANOMAT 2006); 2006

Bulk metallic glasses can be obtained in the Mg-Cu-RE (RE: Rare Earth) systems. These amorphous alloys usually exhibit high strength and brittle fracture. However, It was observed that the partial substitution of Cu by Al can improve the ductility of these amorphous alloys. In the present work the glass forming ability, the stability and the crystallisation process of melt-spun Mg65Cu25MM10 and Mg65Cu20Al5MM10 (at%) alloys were analysed by means of X-ray diffraction and differential scanning calorimetry. The alloy without Al content exhibited three crystallization steps, the first and the second ones being overlapped. The alloy containing Al exhibited three separated crystallization steps. It was observed that Al increased the crystallisation and the melting temperatures. The apparent activation energy of the crystallisation steps were determined and the Al effect on the glass forming ability is discussed.