Abstract
The effect of green powder composition and centrifugal overload n on combustion temperature, separation of metallic products from ceramic phases, chemical composition and microstructure of intermetallic Ti-Al-Nb alloys prepared by Self-propagating High-temperature Synthesis (SHS) in a centrifugal machine was investigated. It was found that SHS can be performed in a combustion mode by addition of energy-producing CaO₂+Al components into the product-forming Ti + Nb + Al or TiO₂ + Nb₂O₅ + Al powder mixtures. The yield of a metallic product increases, porosity decreases and microstructure significantly changes with increasing n. The presence of CaO in combustion products and centrifugal overload facilitates almost complete separation of ceramic phases from the metallic product. The uniform microstructure of metallic products and chemical composition close the targeted Ti-46Al-8Nb (at.%) can be achieved by an appropriate selection of SHS parameters.

Key words
SHS, combustion synthesis, intermetallics, cast titanium aluminides

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