摘要
将低氧碳化硅纤维(KD-Ⅱ)在氩气中分别于1 400、1 600、1 800和2 000℃热处理1 h,对纤维强度和微观结构进行了测试和表征。结果表明,随着热处理温度的升高,KD-Ⅱ中β-SiC晶粒不断长大,孔隙逐渐增多,强度下降。经1 800℃热处理后纤维拉伸强度保持在1 GPa以上。纤维拉伸强度的下降主要是因为β-SiC晶粒的长大、SiC_xO_y相的分解和自由碳的增多。
A precursor - derived SiC fiber with low oxygen content ( KD - Ⅱ) was treated respectively at 1400℃, 1600℃, 1800℃ and 2000℃ for 1 hour in flow argon. The residual strength and microstructures were characterized by XRD and SEM analysis. Results showed that with the temperature increased, the crystal size and porosity of β - SiC in fibers increased while the tensile strength decreased. The strength of fiber could remain over 1 GPa after heat treatment at 1800℃. The strength decrease of the fiber was caused by the growth of β -SiC crystal, decomposition of SiCxOy phase and the increase of the free carbon.
出处
《有机硅材料》
CAS
2017年第1期15-18,共4页
Silicone Material
基金
国防科学技术大学创新群体资助(CJ12-XX-01)
关键词
低氧含量
碳化硅纤维
强度
惰性气氛
孔隙
晶粒
low oxygen content, silicon carbide fiber, intensity, inert atmosphere, porosity, grain