HUANG Zhenren, ＊SHEN Zhijian, LING Luwei, TAN Shouhong,＊Mats Nygren, JIANG Dongliang

(Shanghai Institute of Ceramics ,China Academy of Science , ＊Stockholm University , Swedy)

Abstract: 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·m1/2 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 .

Key words: mullite , silicon carbide whiskers , SPS(Spark Plasma Sintering)processing