Ti3Ni4 precipitation in heat-treated nanocrytalline Ti – 50.9 at. % Ni alloy

The structure of a nanocrystalline Ti–50.9 at. % Ni alloy with mixed subgrain/nanograin structure is investigated by transmission electron microscopy after annealing at temperature 400°C. The size, morphology and distribution of Ti3Ni4 particles formed in the process of the decomposition of a TiNi B2 solid solution are investigated. It is shown that the Ti3Ni4 particles precipitate in the substructure in the low-angle boundaries regions. The precipitation of coherent particles in subgrains is possible with the latter sizes less than 100 nm. At the same time, precipitations of Ti3Ni4 particles are not observed inside the nanograins.The structure of a nanocrystalline Ti–50.9 at. % Ni alloy with mixed subgrain/nanograin structure is investigated by transmission electron microscopy after annealing at temperature 400°C. The size, morphology and distribution of Ti3Ni4 particles formed in the process of the decomposition of a TiNi B2 solid solution are investigated. It is shown that the Ti3Ni4 particles precipitate in the substructure in the low-angle boundaries regions. The precipitation of coherent particles in subgrains is possible with the latter sizes less than 100 nm. At the same time, precipitations of Ti3Ni4 particles are not observed inside the nanograins.