Ultrahigh temperature processing by concentrated solar energy with accurate temperature measurement

An ultrahigh temperature solar processing platform consisting of a High-Flux Solar Simulator (HFSS) and auxiliary equipments is developed to research high-temperature materials and processes. Refractory metals of zirconium (melting point of 1855 degrees C), niobium (2477 degrees C) and tantalum (3017 degrees C) were successfully melted by concentrated light from xenon lamps of the HFSS. The melting experiment was monitored by a charge-coupled device camera, and the temperature was recorded by a near-infrared multi-wavelength pyrometer. Then the processed metals were examined by SEM and EDS to compare the difference before and after the ultrahigh-temperature experiments. In addition, a numerical model combining Monte-Carlo ray-tracing method and finite-element method was established to simulate the melting process, the results of which agreed well with experimental results. Furthermore, melting temperatures measured by the well-calibrated near-infrared multi wavelength pyrometer were close to the melting points of the refractory metals (i.e., +/- 2% relative error). The experimental platform also demonstrates the capability of providing high radiative flux and ultrahigh temperatures (> 2000 degrees C) for the calibration of heat flux gauges and the testing of high-temperature properties of materials. The concentrated solar energy based ultrahigh temperature technology provides an innovative approach for processing refractory materials in general.