TiB2相含量对SiC-B4C-TiB2三相复合陶瓷微观结构演变和力学性能影响研究
Effect of TiB2 on Micro structure Evolution and Mechanical Properties of SiC-B4C-TiB2 Composite Ceramics
王雯龙 1陈刚 1刘凯 1王红杰 1申震 1田兆永 1谭波 1寇亦非 1刘光1
作者信息
- 1. 中国兵器科学研究院宁波分院,浙江宁波 315000
- 折叠
摘要
以SiC、B4C、TiO2和C为原料,通过无压固相烧结原位制备SiC-B4C-TiB2三相复合陶瓷,并系统研究了不同TiB2相含量对复合陶瓷微观结构演变和力学性能的影响.结果表明,TiO2可在烧结过程中完全转化为TiB2相,TiB2含量的增加会促进SiC-B4C复合陶瓷的烧结致密化,当TiB2含量为12 vol.％时,复合陶瓷的最大相对密度达到97.82％,体积密度和表观孔隙率分别为3.12 g·cm-3和2.6％.复合陶瓷的力学性能随着密度的增加而提高,抗弯强度、维氏硬度和断裂韧性最高分别达到(491±24)MPa、(30.1±0.8)GPa和(5.17±0.23)MPa·m1/2.SiC-B4C-TiB2三相复合陶瓷增韧机制以残余热应力增韧为主,裂纹偏转和弥散颗粒相的钉扎等机制协同增韧.
Abstract
SiC-B4C-TiB2 three-phase composite ceramics were prepared by using pressureless solid-phase sintering,with SiC,B4C,TiO2 and C as raw materials.It is found that TiO2 can be completely converted to the TiB2 during the sintering process.Simultaneously,densification of the SiC-B4C composite ceramics during sintering was promoted by the increase in the content of TiB2.The maximum relative density,bulk density and apparent porosity of the composite ceramics with 12 vol.％TiB2 reached 97.82％,3.12 g·cm-3 and 2.6％,respectively.Mechanical properties of the composite ceramics are positively correlated with their relative density.Flexural strength,Vickers hardness and fracture toughness of the samples reached(491±24)MPa,(30.1±0.8)GPa and(5.17±0.23)MPa·m1/2,respectively.Toughening mechanism of the SiC-B4C-TiB2 three-phase composite ceramics was dominated by the toughening of residual thermal stresses.Mechanisms such as crack deflection and immobilisation of diffuse particulate phases were present to achieve synergistic toughening.
关键词
无压烧结/复合陶瓷/微观结构/力学性能Key words
pressureless sintering/composite ceramics/microstructure/mechanical properties引用本文复制引用
基金项目
宁波市2025重大科技攻关项目(2022Z008)
出版年
2024
国家科技期刊平台
NSTL
万方数据