Characterization of infrared absorption by powder coatings on steel panels

Interest in faster curing systems has led to infrared (IR) curing of powder coatings. The efficiency of IR heating depends on both the coating spectra l absorption characteristics and the spectral emissions of the infrared sou rce. Coating spectral absorptivities were measured with an FTIR spectromete r with an integrating sphere. Using the spectral absorptivities and normali zed blackbody emissions, integrated average absorptivities and overall radi ant efficiencies were calculated for blackbody emitter temperatures ranging form 500 to 3000 K (440 to 4949 degrees F). The effects of several powder coating parameters on spectral absorptivities, integrated average absorptiv ities, and overall radiant efficiencies were studied.