摘要
研究了采用先驱体转化 -热压烧结制备的单向Cf/SiC复合材料室温 ,15 73,172 3,192 3K温度下力学行为 ,并从显微结构的特征分析了单向Cf/SiC复合材料高温力学行为的变化原因 .结果表明 :Cf/SiC复合材料的室温 ,15 73,172 3 ,192 3K温度下弯曲强度分别为5 5 0 ,392 ,394,5 74MPa ,弯曲模量分别为 15 7,14 8,132 ,83GPa .Cf/SiC复合材料破坏时 ,其破坏方式将从室温和 15 73K的分层断裂向172 3K ,192 3K的脆性断裂转化 .Cf/SiC显微结构的分析表明 ,在纤维周围和大晶粒间存在着大量的有一定结晶程度的玻璃相 。
The bending behavior of C f/SiC composites prepared by precursor pyrolysis and hot pressing was studied at temperatures from RT to 1 973 K. The changes of the mechanical behavior at different temperatures were explained by the changes in microstructure. The results show that the UD_C f/SiC composites′ bending strength and modulus at RT, 1 573, 1 723, 1 923 K are 550, 392, 394, 574 MPa and 157, 148, 132, 83 GPa, respectively. The fracture behavior changes from delaminating mode at RT and 1 573 K to brittle mode at 1 723 K and 1 923 K. It is found from the HRTEM images that there are a glass layer in the fiber/matrix interface and the interface between SiC powders. The softening of the glass layer at high temperature will strongly influence the high temperature mechanical behaviors of the C f/SiC composites.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2001年第5期435-438,共4页
Journal of The Chinese Ceramic Society
基金
国防预研重点资助项目 ( 12 .1.4.3)
