APPLICATION OF CALCIA CRUCIBLE TO MELT HIGH PURITY ALLOYS

A new process melting the high purity alloys by using calcia crucible has been developed. The calcia crucible with excellent refining and keeping temperature properties is made successfully in 10 kg vacutun induction furnace. The purified experiment of pure iron and GH169 alloys was carried out in vacuum induction furnace and adding Al, La and Ca as cleaner. In 10 kg vacuum induction furnace and tinder condition of 1.5 - 2.5 Pa vacuum and 1400 ℃,the contents of N, O and S in alloy GH169 are reduced to less than 20×10-4%, 20×10-4% and ×10-4% from 70×10-4%, 33×10-4% and 35× 10-4%, respectively. The refilling mechanism of calcia crucible was discussed.