Amorphous ribbons consolidation of Cu46Zr42Al7Y5 alloy by hot extrusion

The Cu46Zr42Al7Y5 alloy with amorphous structure shows a temperature range between the glass transition temperature (Tg) and the crystallization temperature (Tx) of Tx-Tg=ΔTx= 100K. At this temperature range, the metal behavior is of a supercooled liquid with viscosity ≅ 106 N.s/m2. The aim of this work is to contribute on the development of a processing route to produce bulk metallic glass. Amorphous ribbons was produced by rapid quenching using 'melt spinning' process, the ribbons were fragmented in small pieces, compacted at room temperature and consolidated by hot extrusion under extrusion temperatures on the ΔTx, ram speed of 1mm/min and extrusion ratio of 3:1. The extruded samples were characterized by X-ray diffractometry (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The results showed that extrusion temperature was fundamental to promote a full or partial consolidation of the amorphous ribbons, but causing the formation of some voids and inducing some regions to crystallization that showing the high sensibility to fit the extrusion temperature.(author)