Titanium, its alloys, and refractory compounds are often used in the compositions of surfacing materials. In particular, under the conditions of electron-beam surfacing the use of synthesized composite powder based on titanium carbide with a metal binder (TiC-Me) has a positive effect. These powders have been prepared via the self-propagating high-temperature synthesis (SHS) present in a thermally-inert metal binder. The initial carbide particle distribution changes slightly in the surfacing layer in the high-energy rapid process of electron-beam surfacing. However, these methods also have their limitations. The development of technologies and equipment using low-energy sources is assumed. In this case, the question of the structure formation of composite materials based on titanium carbide remains open, if a low-energy and prolonged impact in additive manufacturing will be used. This work reports the investigation of the sintered powders that were previously synthesized by the layerwise combustion mode of a mixture of titanium, carbon black, and metal binders of various types. The problems of structure formation during vacuum sintering of multi-component powder materials obtained as a result of SHS are considered. The microstructure and dependences of the sintered composites densification on the sintering temperature and the composition of the SH-synthesized powder used are presented. It has been shown that under the conditions of the nonstoichiometric synthesized titanium carbide during subsequently vacuum sintering an additional alloy formation occurs that can lead to a consolidation (shrinkage) or volumetric growth of sintered TiC-Me composite depending on the type of metal matrix used.

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The phase composition, microstructure and morphology of composite powders «TiC-HSS steel binder» obtained by the SHS method in layerwise combustion mode have been studied. Titanium powder, carbon (carbon black) in a ratio corresponding to equiatomic titanium carbide and high speed steel as a thermally inert binder was used as a reaction mixture. It was found that the mass transfer of reaction mixture components between the carbide and metal binder was taking place during synthesis, as a result of which the final phase and elemental composition of the synthesis products was formed. It is shown that the volume content of thermally inert binder significantly affects the dispersion of the formed carbide phase.

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The paper examines bulk changes and evolution of the microstructure and phase composition in solid-phase sintering of titanium and TiAl 3 powder mixtures. Metallography, x-ray diffraction, and electron microprobe analysis are used to ascertain the sequence of structural transformations during isothermal holding in sintering. Samples with high content of TiAl 3 intermetallide powder substantially expand during sintering since TiAl 3 particles dissociate leaving pores behind and TiAl particles grow pushing each other away.

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