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The effects of the most important parameters of hot pressing, including temperature, time and pressure on densification, microstructure and infrared transparency of MgF2 ceramics are discussed. The results show that the absorption or scattering of incident radiation is strongly dependent on the amount of porosity. By increasing the temperature or the pressure, transparency at infrared wavelengths has been increased due to the rise in density. For the longer hot pressing times, a continuous increase in density and infrared transparency has been seen as well. Cold pressing before hot press has minor effects on the density and infrared transparency of MgF2. © 2008 Elsevier B.V. All rights... 

In this paper, a conceptual study and quantification of using a thermophotovoltaic system (TPV) to convert incident radiation on furnace panels to electrical energy is presented. In typical electric arc furnaces (EAF), a considerable amount of energy is wasted during the melting process, that is, steel enthalpy, off-gas extraction, vessel cooling, slag enthalpy, and others. Although a remarkable share of the energy is wasted in circulating water, the contained exergy is simply too low to be considered for heat recovery (under 0.5% of input exergy) in comparison to energy content of the extracted gasses and slag. In the performed study, a TPV power output is calculated as a function of arc...