On the Influence of the Furnace and Cell Conditions on the Phase Transition of the Eutectic Co-C

This paper considers the influence, in terms of temperature and time, of the following three factors on the phase transition of high-temperature fixed points: the temperature gradient of the furnace along the fixed-point cell, the thermal inertia of the furnace, and the thermal condition of the cell itself. Melting and freezing experiments have been performed for the eutectic Co-C in a three-zone furnace, of which the temperature gradient along the cell could be varied from positive to negative. To help the interpretation of these experiments, a realistic 2D finite-element model has been implemented, simulating the three influence factors. The model allowed us to understand the features observed in the melts and associated freezes, for the different furnace conditions, not only qualitatively but also quantitatively. This research identifies the essential requirements to facilitate the optimum configuration of the furnace and cell design.