Denitrogenation and desulphurization during vacuum induction melting
refining Ni-base super alloy
refining Ni-base super alloy
(1. The Institute of Metal Research, The Chinese Academy of Sciences,
Shenyang 110016, China;
2. Department of Materials Engineering, Shenyang University,
Shenyang 110044, China)
Shenyang 110016, China;
2. Department of Materials Engineering, Shenyang University,
Shenyang 110044, China)
Abstract: The denitrogenation and desulphurization behavior during vacuum induction melting (VIM) refining Ni-base superalloy using CaO crucible was studied. It has been found that the desulphurization process did not occur by only using CaO crucible. Combining with the results of XRD and composition analysis, the desulphurization mechanism of CaO crucib le was proposed. Al addition limits effect on denitrogenation, but it is very important for desulphurization. Ti addition has adverse effect on denitrogenation. The increase of vacuum is a powerful measurement to accelerate the denitrogenat ion process.
Key words: Ni-base superalloy；VIM (vacuum induction melting)；CaO crucible；denitrogenation； desulphurization