Comparison of the Pore Structure of Calciothermic and Magnesiothermic Niobium and Tantalum Powders

Using the TERRA software suite, we have evaluated the adiabatic temperature of reactions of Ta2O5 and Mg4Ta2O9 with calcium (2900 and 2362 K, respectively). We have carried out a comparative analysis of the pore structure of niobium and tantalum powders prepared via magnesium and calcium vapor reduction of niobium and tantalum oxide compounds and identified characteristic features of the pore structure of these types of powder. Assumptions are made as to the causes of the formation of the coarser pore structure of the calciothermic powders.