Processing conditions, structural evolution, and mechanical properties of Fe–28Al, prepared by two‐step sintering technology

Two technological modes for the production of Fe‐Al intermetallics were used: pressureless vacuum sintering of samples consolidated from a mixture of elementary powders or the mode including pre‐sintering of consolidated samples at 1050 °C, their repressing, and subsequent high‐temperature vacuum sintering. The effect of sintering temperature and mode of manufacturing on the phase composition, structure, and physical and mechanical properties of the intermetallic compound has been studied. It is shown that a significant increase in density and strength properties occurs at a sintering temperature exceeding 1350 °C. The use of the second mode for production with the sintering temperature of 1450 °C allows to obtain samples with a porosity that does not exceed 5 % with the best level of mechanical properties. The creep investigations of the obtained material show that the use of powder metallurgy technology allows to provide sufficiently high values of high‐temperature properties of iron aluminide. The analysis of creep parameters of sintered iron aluminide at different temperatures and loads made it possible to establish the occurrence of mainly the dislocation mechanism of creep.