FeAl materials from intermetallic powders

FeAl materials with the aluminium concentration of 40 at.% were prepared from intermetallic powders, obtained by milling and screening of the products of self-propagating high-temperature synthesis (SHS), carried out in a loosely packed mixture of elemental powders. Pressureless sintering of the compacted intermetallic powders yielded porous materials that were densified by hot forming. The properties of dense bodies were strongly related to the grain size of the starting intermetallic powders. Two fractions with grain sizes of less than 25 μm and in the range from 25 to 40 μm were investigated. The amount of an oxide phase distributed along the grain boundaries of the intermetallic matrix was remarkably higher in the former case. The oxide dispersions adversely affected the room temperature strength and ductility of the material.