PREPARATION OF BULKY ZR-BASED AMORPHOUS-ALLOYS BY A ZONE-MELTING METHOD

A bulk amorphous Zr60Al10Ni10Cu15Pd5 alloy was prepared by the zone melting method using an are-type heat source. The bulk amorphous alloy prepared on the copper hearth has a rectangular parallelepiped shape with a thickness of 10 mm, a width of 12 mm and a length of 170 mm. A majority of the region except the bottom and side edge regions contacted with copper hearth consists of an amorphous phase. The cooling rate achieved by the zone melting method is high enough to cause an amorphous phase in the Zr-based alloy where heterogeneous nucleation is suppressed. The amorphous phase subjected to continuous heating exhibits a distinct glass transition, followed by a wide supercooled liquid region and then an exothermic peak due to crystallization. The success of producing the bulk amorphous alloys by the zone melting method implies the possibility of the continuous production of the bulk amorphous alloys and seems to accelerate the subsequent progress of amorphous alloys.