Thermal explosion synthesis of aluminum matrix composites reinforced with TiC-TiB_2 ceramic particulates

In situ TiC-TiB2 diphase ceramic reinforced aluminum metal matrix composites were successfully fabricated via thermal explosion(TE) reaction in the Al-Ti-B4C system. Using DTA and XRD analyses,the combustion reaction characteristic was examined. The results show that Al serves not only as a diluent but also as a reaction participant,affecting the reaction process and its final products. Combining with the DTA and the TE temperature-time curves,the ignition temperature is estimated to be about 970 K. With increasing Al content,the adiabatic combustion temperature is lowered and the sizes of the TiC and TiB2 particulates decrease. When the Al content in the reactants is more than 50%,Al3Ti intermediate phase is detected in the synthesized products. SEM observations reveal that the nearly spherical TiC particles and hexagonal or rectangular TiB2 particles distribute relatively uniformly in the Al matrix.

In situ TiC-TiB2 diphase ceramic reinforced aluminum metal matrix composites were successfully fabricated via thermal explosion （TE） reaction in the Al-Ti-B4C system, Using DTA and XRD analyses, the combustion reaction characteristic was examined. The results show that Al serves not only as a diluent but also as a reaction participant, affecting the reaction process and its final products. Combining with the DTA and the TE temperature-time curves, the ignition temperature is estimated to be about 970 K. With increasing Al content, the adiabatic combustion temperature is lowered and the sizes of the TiC and TiB2 particulates decrease. When the Al content in the reactants is more than 50%, AlaTi intermediate phase is detected in the synthesized products. SEM observations reveal that the nearly spherical TiC particles and hexagonal or rectangular TiB2 particles distribute relatively uniformly in the Al matrix.