Combustion Synthesis of a Composite Material from a Ti + 2B Mixture and 3Ni + Al Composite Particles

Abstract—A porous intermetallic/ceramic interpenetrating phase composite has been produced by self-propagating high-temperature synthesis (SHS) in samples of the Ni–Al–Ti–B model system. The starting mixture was prepared using composite granules (with the composition 3Ni + Al) produced by mechanical activation and a mixture of titanium and boron powders (with the composition Ti + 2B). The SHS process was run in the combustion regime. Two main chemical reactions occurred in the combustion wave: between aluminum and nickel in the granules and between titanium and boron in the mixture around the granules. Combustion was accompanied by the formation of a porous TiB₂ skeleton around the granules, into which molten nickel aluminides infiltrated from the granules. The solid phase of the SHS product contained interpenetrating fine-grained intermetallic and diboride skeletons. The composite had appreciable porosity on different scales.