A Strategy for Phase Identification of Precipitates in High Al-containing Austenitic and Ferritic Steels Using Electron Diffraction

Abstract

A strategy for phase identification of precipitates in high Al-containing austenitic and Al-containing precipitates (k-carbide, Ni3Al, Fe3Al, FeAl) show the similarities of crystal ferritic steels using electron diffraction (ED) is studied. Comparative studies of the various Al-containing precipitates (k-carbide, Ni3 structure and lattice parameter. However, the slight differences of lattice parameter and Al, Fe3 Al, FeAl) show the similarities of crystal structure and lattice parameter. However, the slight differences of lattice parameter structure display characteristic ED patterns (EDPs) which can be identified. L12 k-carbide and structure display characteristic ED patterns (EDPs) which can be identified. L12 k-carbide and Ni3 Al can be differentiated by the length of g (the reciprocal lattice vector), and Ni3Al can be differentiated by the length of (the reciprocal lattice vector), even even though they show perfectly identical shapes of EDPs. DO3 Fe3 Al and B2 FeAl show though they show perfectly identical shapes of EDPs. DO3 Fe3Al and B2 FeAl show the the characteristic EDs in [110] and [112] beam directions due to the differences of Fe site occupancies in unit cells. k-carbide, Ni3 characteristic EDs in [110] and [112] beam directions due to the differences of Fe site Al, and FeAl show also the similar EDs in [112], [112], and [110] beam directions, respectively. All the possible similarities of EDs among each phases and the strategy for phase identification are discussed on the bases of occupancies in unit cells. k-carbide, Ni3Al, and FeAl show also the similar EDs in [112], kinematical ED simulation.