from the conferences organized by TANGER Ltd.
Deposits of 92/8 at.% Ti/Ni were produced by low-pressure cold spray technique using heated air as working gas. The chemical composition of the 8 mm thick was kept in hypoeutectoid concentration. Samples of the deposited material were annealed at temperatures from 500 to 1000 °C for two hours in argon protective atmosphere. Selected samples were quenched directly from the homogenizing temperature of 1000 °C and subsequently evolution of precipitated eutectoid was studied. Generally microstructural changes of material character during annealing were evaluated together with changes in the character of fracture behaviour and local micro hardness of the evolved phases. Microstructure and chemistry of the newly formed phases was evaluated using analytical electron microscopy. DSC study was involved in order to characterize the precipitation behaviour under eutectoid temperature. Gradual evolution of intermetallic phases by diffusion mechanism was observed. The samples general shape was preserved during the heating process although formation of Kirkendall porosity was evident. First occurrence of intermetallic phases was observed at 600 °C. The evolved phases incurred by diffusion mechanism and included phases close to Ti2Ni, TiNi, and TiNi3.
Keywords: Cold spray, reaction synthesis, intermetallics, diffusion, metallic foam© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.