| Abstract |
| Dispersed particles of (3 and 10) wt.% Si3N4 were incorporated into Ti-50 at alloys via a mechanical alloying-spark plasma sintering (MA-SPS) technique. Since Si3N4 was chemically incompatible with TiAl, Si3N4 decomposed into silicon and nitrogen during sintering and the subsequent exposure to air at 1100℃ for 100 hr. The decomposition of Si3N4 resulted in the formation of Ti5Si3, nitrides such as Ti2AlN and TiN, and voids in the matrix. Although Si3N4 was unstable in the TiAl matrix at high temperatures, Si3N4 increased the oxidation resistance, forming a thin scale on the surface of the Ti-50 at.% Al-(3, 10) wt.% Si3N4 composites. |
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| Key Words |
| titanium aluminide, silicon nitride, sintering, oxidation |
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