Investigations of the structure of porous titanium nickelide after thermal treatment

Methods of optical metallography, scanning electron microscopy, and x-ray structural and spectral microanalyses are used to investigate the structural features of porous titanium nickelide produced by the method of self-propagating high-temperature synthesis (SHS) after its thermal treatment. It is demonstrated that the clearly expressed structural-phase inhomogeneity observed in porous titanium nickelide after SHS is retained after thermal treatment. During thermal treatment with increase in the annealing temperature, the volume fraction of the Ti₂Ni phase enriched in titanium remains essentially unchanged; it is redistributed over the sample volume. The volume fraction of the TiNi₃ phase increases and nonuniformity in its density distribution over the sample volume, caused by the chemical inhomogeneity of the matrix, is observed. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 86–92, October, 2008.