Abstract
Self-propagating high-temperature synthesis (SHS), also called as combustion synthesis, has advantages such as energy efficiency, simplicity, high reaction temperature and productivity.
The TiAl-based composite materials containing TiB2 and Ti2AlN were combusion-synthesised within few seconds from the mixed reactants of Ti+(0.7-0.95)Al+(0.05-0.50)B under nitrogen gas atmosphere of 30-100atm. The combustion temperature exceeded the melting points of TiAl and Ti2AlN, and hence most parts of the composite was fused due to high reaction heat. The molten product was isostatically pressed by surrounding nitrogen gas. The products solidified were fully dense without cracks, which consist of homogeneous grains of -10μm due to rapid cooling after the SHS reaction. The use of pressurized reactive gas such as nitrogen was found to be very effective for simultaneous synthesis and consolidation of nitride ceramics-dispersed TiAl intermetallic compound.
