Volumetric Reduction of the FeCl2–CaCl2 Melt by Calcium Dissolved in Calcium Chloride

The purpose of this study is to fabricate highly dispersed powder suitable for spheroidization with further application in additive technologies. The volumetric reduction of the FeCl2–CaCl2 melt by calcium dissolved in CaCl2 produced a fine iron powder. The process included three states, notably, the preparation of melts containing FeCl2 and Ca, their mixing, and high-temperature aging at 800°C for 1 h. Upon finishing the process, the solidified fusion cake is divided into top and bottom parts. The product from the top part has a specific surface of 7.60 m2/g, and that from the bottom part has a specific surface of 5.38 m2/g. The average particle size is 157 μm for the former and 124 μm for the latter. Ultrasonic dispersing is reduced to 26 μm and 71 μm, respectively. Quantitative X-ray phase analysis shows that the main phase of powder is metallic iron (more than 97 wt %). Thus, the originality of the research is due to the application of an intense volumetric reduction of iron from chloride melts by calcium dissolved in its chloride. The uniqueness of the study is due to its product, so far as the main part of reduced iron is arranged in the melt bulk in the form of linear aggregates 40–600 μm in length and 10–50 μm in diameter, which easily destruct by ultrasonic dispersal into separate crystals with an average size of 26 μm. The results of the study show the possibility of implementing the calcium-thermal production of fine iron powder.