CAJ | 학술논문

将 PCS 电子束交联丝在氨气氛中氮化热解、脱碳氨化,继在氮气氛中高温热引发缩合/转氨基反应,生成硅氮烷并最终形成氮化硅(Si3 N4)纤维。所制备的 Si3 N4纤维白色透明,横截面和表面均光滑致密,无明显缺陷和孔洞。还研究了氮化热解的反应机理以及热解工艺对氮化硅(Si3 N4)纤维结构和性能的影响。红外光谱和元素分析的结果显示,氮化热解脱碳彻底,Si3 N4纤维 C 含量<1%；烧结温度提高,N含量随之增加,O 含量则先增后减；烧结温度不超过1500℃,纤维为无定型。力学性能结果分析表明,随热解温度的提高,纤维力学性能先提后降,1300℃时达到最大值。氮化热解过程是采用NH3进行脱碳氨化,并在N2气氛下高温热引发缩合/转氨基反应产生硅氮烷并最终形成Si3 N4的过程。
장 PCS 전자속교련사재안기분중담화열해、탈탄안화,계재담기분중고온열인발축합/전안기반응,생성규담완병최종형성담화규(Si3 N4)섬유。소제비적 Si3 N4섬유백색투명,횡절면화표면균광활치밀,무명현결함화공동。환연구료담화열해적반응궤리이급열해공예대담화규(Si3 N4)섬유결구화성능적영향。홍외광보화원소분석적결과현시,담화열해탈탄철저,Si3 N4섬유 C 함량<1%；소결온도제고,N함량수지증가,O 함량칙선증후감；소결온도불초과1500℃,섬유위무정형。역학성능결과분석표명,수열해온도적제고,섬유역학성능선제후강,1300℃시체도최대치。담화열해과정시채용NH3진행탈탄안화,병재N2기분하고온열인발축합/전안기반응산생규담완병최종형성Si3 N4적과정。
In this work,PCS cured fibers were pyrolysis nitridation in the ammonia atmosphere for carbon re-moval and amination,and then condensation/nitridation reaction at high temperature in the nitrogen to produce Si3 N4 fibers.Results showed that as-prepared Si3 N4 fibers were colorless and transparent.What was more,the skin of the fiber was smooth and the cross section was rather dense without identifiable defects.This paper also discussed the mechanism of nitridation and the influence of pyrolysis conditions on the structure and properties of Si3 N4 fibers.The results of FT-IR spectra and elemental analysis showed that the carbon content was ex-tremely low after amination and pyrolysis,which was less than 1%,while the nitrogen content increased with the elevated pyrolysis temperature,and the oxygen content first increased and then decreased with the elevated pyrolysis temperature.The fibers were amorphous when the pyrolysis temperature was less than 1500℃,while the tensile strength reached a maximum at 1300℃.The processes of pyrolysis nitridation were a process of de-carburization and ammonification,and then condensation/nitridation at high temperature in the nitrogen,finally producing Si3 N4 fibers.