Papers by Keyword: B₄C-TiB₂

Abstract: In this study, B₄C-TiB₂ ceramic composites were manufactured by hot pressing method. The raw materials for the in-situ synthesis of TiB₂ were TiO₂ and TiC. After being sintered at 1900°C for 60min under a pressure of 30MPa, compact composites samples with a TiB₂ volume fraction range from 0 to 11.05% were prepared. The relative density, fracture toughness and flexural strength of different sample were tested. Microstructures on the fracture surface were studied by SEM. The result shows that B₄C-TiB₂ ceramic composites sintered from B₄C-TiC had a better mechanical property than the one sintered from B₄C-TiO₂. When the content of TiB₂ (reacted from TiC) was 11.05vol.%, the strength and toughness of B₄C-TiB₂ ceramics can reach 598MPa and 6.45MPa·m^1/2. The toughening mechanisms of B₄C-TiB₂ composites include micro-crack toughening and energy consumption by the pulling out process of second phase.

Abstract: This study was carried out to produce and characterize B4C - TiB2 ceramics by spark plasma sintering. Initial B4C and TiB2 powders were mixed in ethanol solution with YSZ balls for 1 hour. Sintering was performed with 5, 10, 15 and 20 volume % TiB2 containing mixtures respectively in disc-shaped graphite dies. The applied pressure was 40 MPa at 1760 °C for 5 minute sintering duration. The improvement of low sinterability and low strength of B4C was investigated as well as strength of flexibility, hardness and fracture toughness. The obtained products were characterized by X-ray diffraction and SEM imaging. The hardness values were measured under 1000 g load and the density values were measured with Archimedes' principle. The 3-point bending tests and modulus of elasticity measurements were also conducted.