1987 Volume 73 Issue 14 Pages 1691-1697
Technical review and experimental study have been conducted on melting process for Ni-base superalloy using calcia refractory.
Experiments were carried out first on denitrogenation for liquid iron, and secondly on reaction between calcia crucible wall and molten Ni containing Hf. Major experiments were carried out on producing Ni-base model alloy, and remelting of IN738 and MarM 247.
These experimental results have revealed that Ni-base superalloy thus made has very low oxygen and nitrogen content below 10 ppm and superior cleanliness, and that calcia refractory has an excellent stability for melting and refining.