Dynamic Compaction of Combustion Synthesized TiC-Al2O3 Composite

Abstract

A dispersed phase TiC-Al2O3 composite was densified and consolidated by dynamic compaction using explosives immediately after it was formed by a combustion synthesis reaction from TiO2, Al, and C powders. By taking advantage of the self-generated heat from the exothermic reaction, this one-step processing technique has the potential for considerable cost savings over conventional processing methods. Near full densification was achieved with samples from 25 to 76 mm in diameter × 6 mm thick. The high-rate densification is necessary to consolidate the ceramic material before heat loss to the containment fixture reduces the temperature to a level below that necessary for bonding. Numerical modeling was used to assist in the design of the fixture and determine the dynamic compression conditions. Good density and strength are achieved by selecting the correct compaction parameters, addressing heat loss, and allowing for evolution of impurity gases.