NEW SOLAR EXPERIMENTAL METHOD FOR MELTING PLATEAU OBSERVATION FOR REFRACTORY OXIDES IN THE RANGE 2000-3000 °C

摘要

We present a new method developed at the Odeillo Solar Furnace (IMP-CNRS) to measure melting and freezing plateau temperatures between 2000 to 3000°C with a controlled plateau duration. The principle is to heat a self crucible product with the solar concentrated flux and to preserve the thermal equilibrium at the temperature melting point with continous regulated solar flux supply. Two critical points are treated: the control of the right level of temperature and its measurement which can be hampered by the solar reflection. Results obtained with Al_2O_3 (melting point = 2046°C) are presented as example.