摘要
以莫来石为基体,SiC晶须(SiC_w)和Y-TZP(Y_2O_3稳定的四方ZrO_2多晶)为两种补强剂,采用热压烧结工艺,制备SIC_w/莫来石和SIC_w/Y-TZP/英来石复合材料。研究了复合材料的力学性能与显微结构,并对强化增韧机制进行了分析。结果表明,SiC晶须补强莫来石,可以改善其强度和断裂韧性。若SiC晶须和Y-TZP共同补强英来石,则可以进一步提高其强度和断裂韧性。晶须引起裂纹偏转,晶须拔出以及由ZrO_2相变引起的微裂纹增韧是该复合材料的主要增韧机制。SiC晶须和Y-TZP两种补强剂的共同作用,对莫来石强度和断裂韧性的提高具有叠加或协同效应。
SiC whisker (SiC_w)/mullite and SiC_w/Y-TZP (yttria stabilized tetragonal zirconia)/mullite composites were fabricated by hot-pressing with SiC whiskers and Y-TZP as reinforcing phases. The mechanical properties and microstructure as well as reinforcing mechanisms were investigated. Flexural strength and fracture toughness of mullite are improved by the addition of SiC whiskers. Significant improvement in flexural strength and fracture toughness will be obtained for the SiC_w/Y-TZP/mullite composite, in comparison with the SiC_w/mullite composite. Reinforcing mechanism in the composite is mainly crack deflection induced by SiC whiskers, pullout of SiC whiskers, and microcrack toughening caused by Y-TZP. Interaction of Y-TZP and SiC whiskers has a superposition or coordination effect on the improvement of strength and fracture toughness of mullite.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
1992年第5期410-416,共7页
Journal of The Chinese Ceramic Society
关键词
莫来石
碳化硅
晶须
陶瓷复合材料
mullite
silicon carbide whisker
yttria-stabilized tetragonal zirconia polycrystals
composite
reinforcing mechanism
