High strength ceramics such as boron carbide (B4C) exhibit exceptional performance under impact up to the Hugoniot elastic limit (HEL), but apparent brittle failure after the HEL results in an immediate loss of strength prior to a rise to the peak Hugoniot state. By contrast, materials with more plasticity prior to failure such as silicon carbide (SiC) and titanium diboride (TiB2) exhibit hardening following the HEL. In order to enhance the toughness of high performing ceramics, blends of ceramic materials have been fabricated in a ceramic-ceramic composite structure. Here, two variants of B4C-23.vol%TiB2 ceramic composite processed through spark plasma sintering (SPS), one with initially coarse TiB2 powders and the other with initially fine TiB2 powders, are investigated under shock loading. The HEL and post-HEL responses are discussed and compared to monolithic SPS processed B4C. The ceramic composite exhibited enhancements in both the HEL and post-HEL response as compared to the monolithic material. Initial TiB2 powder size played only a minimal role in the dynamic mechanical response of the materials where the large powders resulted in similar HEL and post-HEL response with a slight increase in the scatter in data.