Behavior of Nitrogen in GH4169 Superalloy Melt during Vacuum Induction Melting Using Returned Materials

The nitrogen behavior of superalloy melt GH4169 during the vacuum induction melting (VIM) process was clarified by using different proportions of returned materials including block-shaped returned material, chip-shaped returned material, and pure materials to produce a high–purity superalloy melt an...

Full description

Saved in:
Bibliographic Details
Published in:Metals (Basel ) 2021-07, Vol.11 (7), p.1119
Main Authors: Gao, Shengyong, Wang, Min, Xie, Xiaoyu, Liu, Meng, Bao, Yanping
Format: Article
Language:English
Subjects:
Alloys
Chemical reactions
denitrification
Flotation
Gasification
Liquid phases
Low vacuum
Mass transfer
Mechanical properties
Metallurgy
Nickel
Nitrides
Nitrogen
Nitrogen removal
Raw materials
returned materials
Sulfur
superalloy
Superalloys
Vacuum induction melting
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The nitrogen behavior of superalloy melt GH4169 during the vacuum induction melting (VIM) process was clarified by using different proportions of returned materials including block-shaped returned material, chip-shaped returned material, and pure materials to produce a high–purity superalloy melt and provide guidance for the purification of the superalloy melt. For the nitrogen removal during the VIM process, the denitrification rate in the refining period reached 10 ppm per hour on average, which is significantly higher than 1 ppm per hour on average in the melting period. The denitrification reaction of superalloy melt GH4169 under extremely low vacuum pressure is controlled by both the mass transfer of nitrogen in the melt and the chemical reaction of the liquid–gas interface. The nitrogen removal of superalloy melts during VIM occurs through the two methods of gasification denitrification and nitride floatation because the nitrides begin to precipitate in the liquid phase at 1550 °C. A higher nitrogen removal rate can be obtained by increasing the proportion of chip-shaped material or decreasing the proportion of block-shaped material.
ISSN:2075-4701
2075-4701
DOI:10.3390/met11071119