Combustion synthesis and densification of NiAl/TiB₂ Composites

Abstract

A suitable combustion synthesis and densification process was designed to fabricate dense NiAl/TiB₂ composites from Ni−Al−Ti−B system. Combustion synthesis processing and microstructure characteristics of products were studied in detail. The results show that the amount of TiB₂ ceramics has a great influence on the combustion synthesis processing and microstructure; with the increase of the amount of TiB₂ ceramics, the combustion temperature and combustion velocity increase rapidly. The volume of synthesized products and the grain size of ceramics particle size are also affected by the amount of TiB₂ ceramics. TiB₂ ceramics fiber can be produced in this synthesis system. The dense NiAl/TiB₂ composites with residual porosity of no more than 1% are fabricated by the combustion synthesis and hot pressing, the mechanical properties of the dense NiAl/TiB₂ composites increase with increase of the amount of TiB₂ ceramics.

Keywords

NiAl/TiB₂ composites / combustion synthesis and hot pressing / microstructure and mechanical properties

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