功能材料
功能材料
공능재료
JOURNAL OF FUNCTIONAL MATERIALS
2014年
5期
5129-5131
,共3页
聚碳硅烷先驱丝%γ射线%Ar%NH3
聚碳硅烷先驅絲%γ射線%Ar%NH3
취탄규완선구사%γ사선%Ar%NH3
polycarbosilane precursor fibers%γ-ray%argon%ammonia
研究了γ辐照聚碳硅烷(polycarbosilane, PCS)先驱丝在Ar与NH3中的热解过程,探讨了气氛与温度对化学结构演变、元素组成、晶型结构和微观形貌的影响。结果表明,热解温度低于600℃时,气氛对化学结构无影响；热解温度达700℃时,Ar 中先驱丝的化学结构主要由 Si-O-Si 和 Si-CH2-Si 构成,而在NH3中发生了 N 与 C 的亲核取代反应,化学结构主要由 Si-O-Si、Si-N H-Si 和 Si-N H 2构成；1000℃时,Ar 中得到β-SiC 晶型的 SiC 陶瓷纤维, NH3中得到无定型Si3 N4陶瓷纤维。
研究瞭γ輻照聚碳硅烷(polycarbosilane, PCS)先驅絲在Ar與NH3中的熱解過程,探討瞭氣氛與溫度對化學結構縯變、元素組成、晶型結構和微觀形貌的影響。結果錶明,熱解溫度低于600℃時,氣氛對化學結構無影響；熱解溫度達700℃時,Ar 中先驅絲的化學結構主要由 Si-O-Si 和 Si-CH2-Si 構成,而在NH3中髮生瞭 N 與 C 的親覈取代反應,化學結構主要由 Si-O-Si、Si-N H-Si 和 Si-N H 2構成；1000℃時,Ar 中得到β-SiC 晶型的 SiC 陶瓷纖維, NH3中得到無定型Si3 N4陶瓷纖維。
연구료γ복조취탄규완(polycarbosilane, PCS)선구사재Ar여NH3중적열해과정,탐토료기분여온도대화학결구연변、원소조성、정형결구화미관형모적영향。결과표명,열해온도저우600℃시,기분대화학결구무영향；열해온도체700℃시,Ar 중선구사적화학결구주요유 Si-O-Si 화 Si-CH2-Si 구성,이재NH3중발생료 N 여 C 적친핵취대반응,화학결구주요유 Si-O-Si、Si-N H-Si 화 Si-N H 2구성；1000℃시,Ar 중득도β-SiC 정형적 SiC 도자섬유, NH3중득도무정형Si3 N4도자섬유。
The pyrolysis process ofγ-ray irradiation curing of polycarbosilane precursor fibers in argon and am-monia atmosphere were studied.The effect of atmosphere and temperature on chemical structure evolution,ele-mental composition,crystal structure and microstructure were discussed.Results showed that the chemical structures of the fibers treated in two kinds of atmosphere had no difference below 600 ℃.At the temperature of 700 ℃,the chemical structures of the fibers treated in argon were composed of Si-O-Si and Si-CH2-Si, while the fibers treated in ammonia composed of Si-O-Si,Si-NH-Si and Si-NH2 .When the temperature reached 1 000 ℃,SiC ceramic fibers withβ-SiC micro crystal were obtained in argon and amorphous Si3 N4 ce-ramic fibers in ammonia.
