TiB.sub.2 -based materials and process of producing the same

摘要

There is disclosed a process for synthesizing TiB.sub.2 composite materials containing a metallic phase. The preparation of these composites comprises providing mixtures of titanium alloys which in addition to at least 30 wt. % titanium also contain F, Ni, Al, Mo, Cr, Co, Cu or mixtures thereof, and boron or ferroboron, reacting these mixtures by local igniting and exothermic reaction or by heating or melting, resulting in the synthesis of composite material containing fine TiB.sub. 2 crystals dispersed in a fine metallic phase which is derived from the metallic element previously alloyed or combined with the titanium of the titanium alloys or the metallic element or elements contained in the ferroboron. By leaching out the metallic phase, fine TiB.sub.2 powders may be obtained. Parts and coatings can also be obtained. The parts are normally obtained by treating the TiB.sub.2 material by powder metallurgic techniques. Coatings may be obtained by thermo or plasma spray depositing on a substrate. Hard facing techniques may lead to TiB. sub.2 composite overlays.