摘要:
Spray-drying was used to produce the high emissivity NiCr
2O
4 powders with a spinel structure. Preliminary investigations focused on fabricating the high emissivity powders for infrared radiation coatings and finding the relationship between microstructure and emissivity. The NiCr
2O
4 powders were characterized for composition, microstructure, and infrared emissivity by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared radiant instrument, and Fourier transform infrared spectra (FT-IR). Thermogravimetry and differential thermal analysis show that the appropriate baking temperature for NiCr
2O
4 powder preparation is about 1200℃. The emissivity measurement and FT-IR spectra show that, because of the special spinel structure, the NiCr
2O
4 powders have a high emissivity about 0.91. Spray-drying is a suitable method to produce the high emissivity ceramic powders.