Design and development of an induction furnace to characterize molten metals at high temperatures
Laurent Dejaeghere, Thomas Pierre, Muriel Carin, Philippe Le Masson and Mickaël Courtois
This work presents the first step concerning the design of a very high temperature inductive furnace dedicated to the characterization of molten metals in the 1 600 K – 2 800 K temperature range. One major constraint is to provide homogeneous temperature within the tested sample and thus avoid thermal gradients as well as magnetic fields. For that, the choice of materials for the furnace design has been made and validated through both a magneto-thermal simulation and some in situ temperature measurements of the sample with both thermocouples until 1 600 K, and with a visible-NIR pyrometer used for the upper temperatures. Experimentally, the pyrometer has been calibrated using the melting temperature measurement of a pure nickel sample placed in the furnace. Finally, the furnace heating capacity limit has been tested and reached during the niobium sample melting. During this test, technical difficulties occurred due to physico-chemical contamination from the crucible.
Keywords: High temperature, furnace, multi-wavelength pyrometer, numerical simulation, characterization, calibration