PRODUCTION OF AL-BASED AMORPHOUS ALLOY WIRES WITH HIGH-TENSILE STRENGTH BY A MELT EXTRACTION METHOD

Al-based amorphous alloy wires with composition Al85Ni10Ce5 were produ ced by a melt extraction method using a copper wheel with a steep edge . The wire has a circular cross section and no appreciable trace resul ting from the use of copper wheel is seen on the outer surface. The wi re diameter is in the range of 40 to 70 mum and tends to decrease with increasing rotation speed of the wheel. The onset temperature of crys tallization, the glass transition temperature and the heat of crystall ization are 531 K, 546 K and 0.37 kJ/mol, respectively, for the wire w ith a diameter of about 70 mum, in agreement with those for the melt-s pun amorphous ribbon with a thickness of about 15 mum. The wires have good bending ductility and a high tensile strength of 950 MPa. The max imum wire diameter of 70 mum is nearly the same as the maximum ribbon thickness for the formation of ductile amorphous alloy with the same c omposition by the conventional melt spinning method. The high cooling rate for the present process is accomplished presumably because the su percooled liquid with a small volume and a large outer surface area to volume ratio is solidified homogeneously without contact of other sub stances.