TiB_(2)相含量对SiC-B_(4)C-TiB_(2)三相复合陶瓷微观结构演变和力学性能影响研究  

Effect of TiB_(2) on Microstructure Evolution and Mechanical Properties of SiC-B_(4)C-TiB_(2) Composite Ceramics

作　　者：王雯龙 陈刚[1] 刘凯[1] 王红杰 申震 田兆永 谭波 寇亦非 刘光[1] WANG Wenlong;CHEN Gang;LIU Kai;WANG Hongjie;SHEN Zhen;TIAN Zhaoyong;TAN Bo;KOU Yifei;LIU Guang(China Academy of Ordnance Science Ningbo Branch,Ningbo 315000,Zhejiang,China)

机构地区：[1]中国兵器科学研究院宁波分院,浙江宁波315000

出　　处：《陶瓷学报》2024年第4期760-766,共7页Journal of Ceramics

基　　金：宁波市2025重大科技攻关项目(2022Z008)。

摘　　要：以SiC、B_(4)C、TiO_(2)和C为原料,通过无压固相烧结原位制备SiC-B_(4)C-TiB_(2)三相复合陶瓷,并系统研究了不同TiB_(2)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,TiO_(2)可在烧结过程中完全转化为TiB_(2)相,TiB_(2)含量的增加会促进SiC-B_(4)C复合陶瓷的烧结致密化,当TiB_(2)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·m^(1/2)。SiC-B_(4)C-TiB_(2)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。SiC-B_(4)C-TiB_(2)three-phase composite ceramics were prepared by using pressureless solid-phase sintering,with SiC,B_(4)C,TiO_2 and C as raw materials.It is found that TiO_2 can be completely converted to the TiB_(2)during the sintering process.Simultaneously,densification of the SiC-B_(4)C composite ceramics during sintering was promoted by the increase in the content of TiB_(2).The maximum relative density,bulk density and apparent porosity of the composite ceramics with 12 vol.%TiB_(2)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·m^(1/2),respectively.Toughening mechanism of the SiC-B_(4)C-TiB_(2)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 

分 类 号：TQ174.75[化学工程—陶瓷工业]