Monochromatic imaging studies of a low pressure arc burning on molten Inconel 718 alloy electrodes during vacuum arc remelting

Conference · Fri Jan 01 00:00:00 EST 1988

OSTI ID:7092735

Williamson, R L; Zanner, F J; Hareland, W A

Vacuum arc remelting (VAR) is a melting and solidification process used to produce high quality ingots of chemically reactive or segregation sensitive alloys. Melting is accomplished through the use of a sustained high current (several kiloamperes) dc arc. Energy from the arc is used to melt a consumable electrode (cathode) which is cast from the alloy to be remelted. The molten material drips down into a water-cooled copper crucible (anode) where it solidifies as a larger diameter, homogeneous, porosity-free, cylindrical ingot. Solidification is driven mainly by radial heat extraction from the molten pool atop the ingot and is influenced by magnetically and buoyancy driven fluid flows that are coupled to the arc behavior. The paper reports the initial results of efforts to characterize the VAR furnace arc during remelting of Inconel 718 alloy using monochromatic imaging. This technique allows one to examine how individual atomic species are distributed throughout the arc plasma in the electrode gap. Because only species existing in excited electronic states are able to emit light, the images also give insight into the energy distribution in the gap. Chromium and manganese distributions were investigated. Chromium was chosen to represent one of the major alloy constituents, while manganese represents a highly volatile trace component. 13 refs., 7 figs.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 7092735
• Report Number(s): SAND-87-2582C; CONF-8804182-1; ON: DE88012855
• Resource Relation: Conference: 9. international vacuum metallurgy conference on special melting, San Diego, CA, USA, 11 Apr 1988; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM
IMAGES
INCONEL 718
VACUUM MELTING
MANGANESE
MECHANICS
ARC FURNACES
DISTRIBUTION
ELECTRODES
ENERGY DENSITY
EXCITED STATES
MONOCHROMATIC RADIATION
PLASMA
SOLIDIFICATION
ALLOYS
CHROMIUM ALLOYS
ELECTRIC FURNACES
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY LEVELS
FURNACES
INCONEL ALLOYS
MELTING
METALS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ALLOYS
PHASE TRANSFORMATIONS
RADIATIONS
TRANSITION ELEMENTS
360101* - Metals & Alloys- Preparation & Fabrication