Spectral-Directional Emittance of High Temperature Oxidized Aluminum

Spectral-directional emittance measurements for high purity aluminum, oxidized in air for an extended period of time (150h) at high temperature are presented. The data presented here cover the spectral range between 3 and 14 μm, directional range from surface normal to 72° polar angle and temperatures from 400 to 600°C with a step increment of 100°C. The measurements were performed using a radiometric, direct emission method. The experimental setup used was comprised of a Fourier transform infrared spectrometer and a blackbody cavity. The Al sample has a nominal surface roughness of 0.635 μm. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were used as surface techniques to characterize the aluminum oxide film that formed on the metallic surface.