Characterization of triplet Ti–TiB–TiC composites: Comparison of in-situ formation and ex-situ addition of TiC

Four hybrid titanium-based samples with different amounts of B4C as reinforcement and the same numbers of specimens with TiB2 + TiC additives were produced using the SPS method at 1200 °C. For a reliable comparison, stoichiometry relations of starting powders were applied to estimate the precise contents of mentioned reinforcements to reach the same vol% of final TiB and TiC phases. The microstructure, relative density (RD), and mechanical properties of both series of SPSed composite samples were studied to make a reliable comparison. The best value of the RD (99.9%) was achieved for the sample doped with 0.48 wt% B4C. The in-situ TiBw phase formation in both series of samples was confirmed using XRD and microscopical evaluations. Samples doped with B4C exhibited better UTS, tensile elongation, and bending strength than the ones doped with TiB2 + TiC. The sample with the least B4C content presented the best value of mentioned mechanical properties. © 2020 Elsevier Ltd and Techna Group S.r.l.