In-situ formed TiCx reinforced Ti composites derived from polyzirconocarbosilane precursor: Synthesis, characterization and mechanical properties

Discontinuously reinforced titanium (Ti) matrix composites (DRTMCs) strengthened by in-situ TiCx particles are synthesized via pyrolysis of polyzirconocarbosilane (PZCS) and pressureless sintering. The Ti matrix reacts with the pyrolysis product of PZCS to form TiCx particles, which effectively refine the α-Ti grains and create a clean, well-bonded semi-coherent interface. A notable orientation relationship is observed between the TiCx and α-Ti phases: (111)_TiCx||(10$\overline{1}$1)_Ti and [$\overline{1}$10]_TiCx||[1$\overline{2}$10]_Ti. The Ti-2PZCS composite demonstrates a significant reduction in average grain size, from 101.5 μm in pure Ti to 39.49 μm, coupled with superior comprehensive mechanical properties: an ultimate tensile strength of 710 MPa, a yield strength of 588 MPa, and an elongation of 9.5 %. The enhanced strength of Ti/PZCS composites is mainly due to grain refinement, solid solution strengthening, and load transfer mechanisms. This study introduces a novel approach for fabricating high-performance Ti composites, highlighting the potential for advanced material applications.