Hematite particles' radiative properties within the ultraviolet-visible spectrum and thermal properties at low temperatures


JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, vol.36, no.1, pp.191-200, 2021 (SCI-Expanded) identifier identifier


The radiative in the UV and visible spectra and the conductivity properties at low temperatures of hematite (alpha-Fe2O3) samples of different particle size distributions and compositions obtained by the pressure welding procedure within temperatures of 900-1100 degrees C were investigated. In this study, the two samples which have different chemical properties were called as Case 1 and Case 2. Debris iron oxides samples, which are in the morphology of hematite, were separated according to particle sizes by sieve analysis. The absorbance-wavelength change and the thermal conductivity-temperature change of the samples of, the smallest, medium and largest of which the particle size were analysed. The coating on particles due to the aging effect was examined using scanning electron microscopy (SEM) images. It has been concluded that the content and size of the particles and the oxidation effect are effective in the variation of the radiation properties of the samples with the wavelength and the temperature of the thermal conductivity coefficient. Radiative and thermal transfer properties of debris hematite particles increase as the particle size increases. However, the radiative property decreases with increasing wavelength and the thermal conductivity property decreases with increasing temperature.