METHOD OF MANUFACTURING NI-TI SHAPE MEMORY ALLOY BY USING DOUBLE MELTING

摘要

The present invention relates to a method of manufacturing a nickel-titanium-based shape memory alloy using a double melting. The method of manufacturing a nickel-titanium-based shape memory alloy using a double melting includes: a vacuum arc melting step of producing a master alloy of titanium and nickel in a vacuum arc remelting (VAR); an introduction melting step of melting titanium and a nickel master alloy by inserting the master alloy in a graphite crucible in a vacuum induction melting (VIM) and performing induction heating on the master alloy; and an alloy forming step of maintaining the temperature of 1350 to 1450 °C by stirring the induction melted titanium and nickel. The nickel-titanium-based shape memory alloy manufactured using a double melting of the VAR/VIM according to the present invention is an alloy containing nickel of 49 to 51 at%, carbon of equal to or less than 500 ppm and inevitable impurities, can be easily manufactured at low cost compared with a case of manufacturing in a calcia crucible, and is satisfied with the size of ASTM F2063 when the carbon content of an implant for medical tools and surgery is equal to or less than 500 ppm.