摘要
通过系统研究烧结温度对SiO_(2f)/SiO_(2)陶瓷基复合材料的密度、孔隙率、微观形貌、拉伸性能、弯曲性能及韧性的影响,获得了高强高韧性复合材料。随着烧结温度升高,材料密度升高;而孔隙率先降后升,归因于基体的收缩增加,且在850℃下收缩严重产生了微裂纹。微观形貌结果表明:随着烧结温度升高,收缩增加,SiO_(2)基体由粗糙变得光滑;基体由颗粒黏接状转变为陶瓷熔融状;且纤维与基体结合由弱变强。随着烧结温度的升高,拉伸强度逐渐降低。拉伸性能主要取决于复合材料的韧性。随着烧结温度升高,弯曲强度先升后降,并在700℃取得最高值71 MPa。只有在基体具备一定强度前提下,韧性才能充分发挥作用。在650℃~750℃烧结温度制度下,复合材料可实现拉伸性能、弯曲性能与韧性的最优化。
The effects of sintering temperature on density,porosity,micromorphology,tensile properties,bending properties and toughness of Si O_(2f)/Si O_(2) ceramic matrix composites were systematically studied,resulting in samples with high strength and high toughness.With increasing sintering temperature,density of the composites is increased.However,the porosity first decreases and then rises,which is attributed to the increase in shrinkage of the matrix and the microcracks produced due to the serious shrinkage at 850℃.With increasing sintering temperature and shrinkage,the Si O_(2) matrix becomes smoother and smoother.Microstructure of the matrix changed from bonded particles to melting ceramics.Meanwhile,the connection between fiber and matrix becomes stronger and stronger.With increasing sintering temperature,the tensile strength gradually decreased,which is mainly dependent on toughness of the composites.The bending strength first increased,then decreased and reached the highest value of 71 MPa at 700℃.Only when the matrix possesses sufficiently high strength,the toughness can fully play its role.At temperatures of 650–750℃,tensile properties,bending properties and toughness of the composites can be optimized.
作者
毛帮笑
夏细胜
王大奎
高国胜
白乐乐
高震洋
吕海花
李晓辰
冯晓雨
MAO Bangxiao;XIA Xisheng;WANG Dakui;GAO Guosheng;BAI Lele;GAO Zhenyang;LYU Haihua;LI Xiaochen;FENG Xiaoyu(Beijing Xinfeng Aerospace Equipment Co.,Ltd.,Beijing 100854,China;Beijing Institute of Electronic System Engineering,Beijing 100854,China)
出处
《陶瓷学报》
CAS
北大核心
2024年第1期125-132,共8页
Journal of Ceramics