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In this investigation, yttria nanopowder was synthesized by precipitation method using yttria micro powder and ammonium hydrogen carbonate as precursor materials. The most important parameters, aging time and calcination temperature, have been reviewed in detail. The effects of aging time (3, 6, 12 and 24 h) and calcination temperature (700o, 800o, 900o, 1000o and 1100oC) were studied. Disk samples were fabricated from nanopowder at 1800oC and 50 Mpa via SPS method. Synthesized phases, thermal behaviour and particle size were shown by X-ray diffraction pattern, thermogravimetry and differential thermal analysis, and field emission scanning electron microscopy, respectively. Fourier transform infrared spectroscopy was used for bonding study before and after heat treatment at different temperatures.

Thermal control has become more and more important in the development of the spacecraft technology. The thermal control coatings are exposed to electrostatic charges that develop on the external surface of the spacecraft. In this research, the synthesis, the surface resistivity, and the influence of the type, percent of the pigments, and adhesive properties on the coating were studied. The weight fraction of the pigment in coatings fabricated by carbon black with a sponge-like structure are lower compared to coatings fabricated by carbon black with a nonporous structure also, the surface resistance decreased with increasing pigment contents.