Synthesis of in-situ TiC-Al composite by dipping exothermic reaction process

Abstract

TiC reinforced Al composites with high volume fraction of TiC were synthesized by a novel in-situ process, a Dipping Exothermic Reaction Process (DERP). The reaction sequences of DERP are as follows: (1) first infiltration of molten aluminum into a porous preform; (2) an exothermic reaction between Ti and C to form TiC; and (3) second infiltration of molten aluminum into the porous skeleton of TiC-Al composites. TiC powder was added as a dilution agent to control the explosive reaction and provided a critical clue to the microstructure variation. In the preform, aluminum powder was used as an activator for the first infiltration. After the initial infiltration, a high exothermic reaction similar to a typical combustion reaction occurred. The high temperature of the exothermic reaction accelerated the second infiltration.