TY - JOUR ID - 4499 TI - Effects of in-situ formed TiB whiskers on microstructure and mechanical properties of spark plasma sintered Ti–B4C and Ti–TiB2 composites JO - Scientia Iranica JA - SCI LA - en SN - 1026-3098 AU - Sabahi Namini, Abbas AU - Azadbeh, Maziyar AU - Shahedi Asl, Mehdi AD - Department of Materials Engineering, Sahand University of Technology, Tabriz, Iran AD - Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil, Iran Y1 - 2018 PY - 2018 VL - 25 IS - 2 SP - 762 EP - 771 KW - Spark plasma sintering KW - titanium KW - Ceramic additives KW - TiB whisker KW - microstructure KW - mechanical properties DO - 10.24200/sci.2017.4499 N2 - Monolithic titanium, Ti–1 wt% B4C, Ti–2.5 wt% TiB2 were spark plasma sintered at 1050 ºC for 5 min under 50 MPa. The effect of B4C and TiB2 additions on densification process, microstructural development and mechanical properties of titanium was investigated. The results revealed that relative density of undoped, B4C- and TiB2-doped Ti samples reached ~98-99%. X-ray diffraction patterns, thermodynamic assessments, and microstructural investigations verified the in-situ formation of TiB whiskers in both composite samples as well as appearance of TiC spheres in Ti–B4C composite. However, trace unreacted TiB2 and B4C additives were remained in the composites as a result of incomplete chemical reactions due to short-time SPS process. Compared to undoped Ti sample, grain growth was hindered when the sample was doped by B4C or TiB2. Elongation, ultimate tensile strength and Vickers hardness of B4C- or TiB2-doped samples were higher than those of monolithic titanium but bending strength of ceramic-doped samples significantly lower, compared to undoped titanium. These outcomes were discussed in detail and related to presence/formation of several ceramic phases with different morphologies in Ti matrix. UR - https://scientiairanica.sharif.edu/article_4499.html L1 - https://scientiairanica.sharif.edu/article_4499_5b904bef8b63842096469abfd8299389.pdf ER -