Titanium alloys with TiB particle reinforcements were prepared from c.p. Ti (grade 2) and FeB as precursors. Both ingot and powder metallurgical methods were utilized. During the first melting or sintering the FeB reacts in situ with titanium and forms TiB and an iron enriched matrix. The TiB particle morphology and size is influenced by the type of reaction (liquid or solid), the temperature and the processing time. Solid state reactive sintering leads to globular aggregates of the reaction products, exhibiting a core-shell structure. Incomplete reactions caused by low temperatures or short reaction times lead to metastable intermediate phases. Liquid phase sintering produces needle shaped TiB in the former molten regions and globular aggregates in regions of solid diffusion. Electron beam melted powder compacts react completely and form small TiB needles with a fine dispersion if the superheating of the melt is low. These ingots are suitable for hot and cold working. Coarse TiB particles exhibit plate and blocky as well as rod shapes. With increasing concentrations of coarse TiB the wear resistance of the alloys is considerably improved. During thermomechanical treatments, various phase transformations between iron stabilized β, TiFe and a take place.
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