无机材料学报2025，Vol.40Issue(4)：405-414,中插13-中插16,14.DOI:10.15541/jim20240439
烧结条件对制备高结晶近化学计量比SiC纤维的影响
Influence of Sintering Conditions on Preparation of Nearly Stoichiometric SiC Fibers with Highly Crystalline Microstructure
摘要
Abstract
Fine-diameter continuous SiC fibers are considered one of the most effective reinforcing fibers for advanced ceramic matrix composites,possessing significant application potential in aerospace and nuclear industries.Among them,near-stoichiometric SiC fibers characterized by a highly crystalline micro structure have garnered considerable attention due to their exceptional high-temperature resistance.However,influence of high-temperature sintering conditions on composition and microstructure of the fibers is still unclear.Here,influences of different sintering temperatures and durations on decomposition of the SiCxOy phase,grain growth and densification of the fibers were systematically investigated.It was found that decomposition of SiCxOy and densification of fibers occur progressively from surface to core.Notably,a specific sintering temperature of 1800℃ was identified as optimal,wherein growth of β-SiC grains effectively compensated for the pore defects resulting from the decomposition of SiCxOy phase,thereby achieving fiber densification.Conversely,excessively high sintering temperature might result in decomposition of β-SiC grains.Although extending sintering duration facilitated removal of residual oxygen within the fibers,it could cause accumulation of graphite phases at β-SiC grain boundaries,leading to an increase in pore defects within the fiber core.Finally,near-stoichiometric SiC fibers with highly crystalline micro structure were successfully fabricated through optimization of sintering conditions,possessing a composition of SiC1.04O0.02Al＜0.01.The β-SiC grains within the fibers were uniformly distributed with sizes ranging from 100 to 200 nm.The fibers exhibited a tensile strength of 1.88 GPa and a Young's modulus of 373 GPa,accompanied by a high density of 3.1 g/cm3.The findings of this research provide a robust foundation for further improving comprehensive properties of SiC fibers.关键词
SiC纤维/烧结/近化学计量比/密度/高结晶Key words
SiC fiber/sintering/nearly stoichiometric/density/highly crystalline分类
化学工程引用本文复制引用
苟燕子,康伟峰,王堋人..烧结条件对制备高结晶近化学计量比SiC纤维的影响[J].无机材料学报,2025,40(4):405-414,中插13-中插16,14.基金项目
国家自然科学基金(52272100) （52272100）
湖南省自然科学基金面上项目(2022JJ30662) （2022JJ30662）
新型陶瓷纤维及其复合材料重点实验室基金项目(WDZC20215250507) （WDZC20215250507）
核反应堆技术全国重点实验室(中国核动力研究设计院)基金(KGSW-0324-0301-08)National Natural Science Foundation of China(52272100) （中国核动力研究设计院）
Natural Science Foundation of Hunan Province(2022JJ30662) （2022JJ30662）
Fund of Science and Technology on Advanced Ceramic Fibers and Composites Laboratory(WDZC20215250507) （WDZC20215250507）
Fund of National Key Laboratory of Nuclear Reactor Technology of Nuclear Power Institute of China(KGSW-0324-0301-08) （KGSW-0324-0301-08）
