碳化硅晶须补强莫来石复合材料的SPS烧结致密化研究  

STUDY ON THE SPS DENSIFICATION OF SiC WHISKER REINFORCED MULLITE COMPOSITES

作　　者：黄政仁[1] 沈志坚[2] 凌律巍[1] 谭寿洪[1] Mats Nygren 江东亮[1] 

机构地区：[1]中科院上海硅酸盐研究所 [2]瑞典斯德哥尔摩大学

出　　处：《陶瓷学报》2001年第3期115-120,共6页Journal of Ceramics

摘　　要：采用SPS工艺制备了SiC晶须增强莫来石基复合材料。SEM分析结果表明 ,SiC晶须在莫来石基体中分布均匀 ,看不到晶须团聚 ,晶粒中可看到由于快速烧结而导致的微气孔残留 ;晶须的拔出、解离非常明显 ,是主要的晶须增韧机制。SiC晶须的取向 ,在热压烧结条件下呈各向异性。在不同方向的裂纹扩展、亦即材料的断裂韧性 ,也表现出明显的各向异性。采用 3 0vol%SiC晶须增强莫来石 ,SPS烧结条件下材料强度比热压高 10 %左右 ,为 5 70MPa ,KIC为 4.5MPa .m1/ 2 ,比纯莫来石提高 10 0 %以上。同HP法烧结相比 。SiC whisker reinforced mullite composites were prepared by SPS(Spark Plasma Sintering)process.SEM analysis showed that the SiC whiskers wer well dispersed in mullite substrate,no agglomerates could be detected,but mini-pores remained due to the fast sintering process.In addition,the pullout,breaking of SiC whiskers were well observed and considered a dominate toughing mechanism.The orientation alignment of SiC whiskers as well the propagation of cracks in different direction(the fracture toughness)exhibited antistrophic behavior.Mechanical measurements showed that the strength and fracture toughness was 570MPa and 4.5MPa·m 1/2 respectively.In comparation with SiC w-mullite composites prepared by hot pressing,an increase of 10% and 100% was obtained.It was showed that SPS method was favorable for the densification process.

关 键 词：碳化硅 晶须补强 莫来石复合材料 SPS工艺 烧结致密化 陶瓷材料 

分 类 号：TQ174.758[化学工程—陶瓷工业]