| 摘要 |
PURPOSE:To produce easily an Ni-Ti alloy wire at a low cost, by melting an alloy consisting of specific ratios of Ni to Ti, and cooling and solidifying the same to a fine wire shape at the cooling rate in a specific range. CONSTITUTION:A crucible 1 having an introducing port 2 for gas and a nozzle 3 is installed in a rotary drum 4 having a shaft 5. An Ni-Ti alloy consisting, by weight, of 50-60% Ni and 40-50% Ti is stored in a molten state in the crucible 1. Cooling liquid such as water is supplied into the drum 4 and the drum 4 is rotated to form laminar flow 6 by centrifugal force. Gaseous argon or the like is then introduced through the inlet 2 to pressurize the molten metal and to inject the same from the nozzle 3 toward the flow 6. The molten metal is cooled to solidify at 10<2>-10<4>deg/sec average cooling rate, whereby a fine wire having a circular section is formed. The Ni-Ti alloy drawn to a fine wire shape is subjected to <=50% cold working then to heat treatment at 300-700 deg.C. |
