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Title: FEEDBACK-BASED CONTROL OVER THE SPATIO-TEMPORAL DISTRIBUTION OF ARCS DURING VACUUM ARC REMELTING VIA EXTERNALLY APPLIED MAGNETIC FIELDS
Ampere Scientific’s VARmetricTM measurement system for Vacuum Arc Remelting (VAR) furnaces passively monitors the distribution of arcs over time during VAR in real time. The arc behavior is known to impact both product yield and quality and can pose potentially catastrophic operating conditions. Arc position sensing with VARmetricTM enables a new approach to control the heat input to the melt pool. Transverse external magnetic fields are applied to push the arcs via the Lorentz force using feedback of the arc location to control the arc. This has been tested on Ampere Scientific’s small-scale laboratory arc furnace with electromagnets used for control for up to 60 seconds while monitoring the arc location with VARmetricTM. The arc distributions are shown to be significantly different from the uncontrolled distributions with distinct thermal profiles at the melt pool. Alternatively, this type of control can be periodically applied to react to undesirable arc conditions.
Authors:
Award ID(s):
1831255
Publication Date:
NSF-PAR ID:
10120902
Journal Name:
Proceedings of the Liquid Metals Processing & Casting Conference
Sponsoring Org:
National Science Foundation
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