Spectral absorptance at 3.8-μ wavelength for aluminum and pyroceram at elevated temperatures

The results of experiments that measure the spectral emittance ελ (hence absorptance) at 3.8-μ wavelength for 6061 aluminum alloy and 9606 pyroceram at elevated temperatures are reported. ελ for 6061 aluminum was measured within the molten state over the surface temperature range of 1200–2100 °F. For 9606 pyroceram, ελ was measured between 1000 and 2000 °F. The data shows that for aluminum, ελ increases linearly with temperature from 0.138 at 1200 °F to 0.190 at 2100 °F. For pyroceram, ελ has an initial value of 0.91 at 1000 °F and slowly decreases to 0.68 at 2000 °F.