Purification of Ti-Al alloys by induction-heating floating-zone melting and cold-crucible melting in ultra-high vacuum

The effect of ultra-high vacuum melting on the purification of Ti-Al alloys, especially on reducing gaseous impurities. is investigated using new Heating-zone melting furnace and cold-crucible melting furnace in which ultra-high vacuum of 10(-7) Fa is attainable, Ulva-high vacuum melting is effective in the purification of Tl-Al alloy, especially in reducing oxygen content. The high purity homogeneous Ti-Al alloy ingot containing 85 mass ppm oxygen is obtained from Ti of 99.99 mass% purity and Al of 99.9998 mass% purity by cold-crucible melting twice in argon and lastly in ultra-high vacuum. The Ti-Al alloy bar prepared from Ti of 99.9999 mass% purity and Al of 99.9998 mass% purity by are melting is further zone-melted under ultra-high vacuum and 36 mass ppm oxygen in the bar is reduced to 13 mass ppm. nle new floating-zone melting furnace and cold-crucible melting furnace which can attain to ultra-high vacuum of 10(-7) Pa are useful for the preparation of high-purity Ti-Al alloy containing low concentration of gaseous impurities.