硅酸盐学报2017，Vol.45Issue(12)：1788-1795,8.DOI:10.14062/j.issn.0454-5648.2017.12.10
粉体合成工艺对TiB2-TiC复相陶瓷微观组织及力学性能的影响
Effect of Powder Synthesis Processing on Microstructure and Mechanical Properties of TiB2-TiC Composite Ceramics
摘要
Abstract
TiB2-44%TiC (in mole fraction) composite ceramics with an eutectic composition were prepared by hot pressing sintering with TiB2-TiC composite powders synthesized by direct and indirect carbon-boron thermal reduction processes, respectively. The effects of the synthesis process and sintering temperature on the microstructure and mechanical properties of TiB2-TiC composite ceramics were investigated. The results show that TiB2 grains in TiB2-TiC composite ceramic sintered with TiB2-TiC composite powder by the direct process are rod-shaped and the microstructure is fine and uniform, while the TiB2 grains in TiB2-TiC composite ceramic sintered with TiB2-TiC composite powder by the indirect processare equiaxed. The density of the composite ceramics increases and the grains grow up, but the mechanical properties changes slightly with the increase of the sintering temperature. The TiB2-TiC composite ceramic prepared by hot pressing sintering at 2000℃ and 30 MPa for 1 h with the direct synthesized composite powder has the optimum comprehensive properties (i.e., relative density of 99.9%, elastic modulus of 537GPa, the Vickers hardness of 19.0GPa, flexural strength of 598MPa, and fracture toughness of 5.3MPa?m1/2 (by indentation method) and 11.6MPa?m1/2 (by SENB). The toughening mechanism of TiB2-TiC composite ceramics is due to crack deflection and branching.关键词
硼化钛-碳化钛复相陶瓷/热压烧结/力学性能/增韧机制/粉末合成工艺Key words
titanium boride-titanium carbide composite ceramics/hot pressing/mechanical properties/toughening mechanism/powder synthesis processing分类
通用工业技术引用本文复制引用
张宇,郭英奎,张馨予,赵彦伟,姚绵懿,王玉金..粉体合成工艺对TiB2-TiC复相陶瓷微观组织及力学性能的影响[J].硅酸盐学报,2017,45(12):1788-1795,8.基金项目
国家自然科学基金(51472060)资助. （51472060）
