摘要
探讨了不连续细长相增强CMCs的增韧效果与细长相方位角θ之间的关系，包括理论模型的简述和SiC晶须定向增强Si3N4材料的试验印证。结果显示，对应微小裂纹扩展而急速增大的一次增韧效果随方位角增大而减小；当方位角处于30°～60°时有二次增韧行为发生，表现为断裂阻抗（韧性）再次随裂纹扩展而缓慢增长并收敛。对增韧机制的方位角依赖性、显微结构参数的影响、断裂阻抗的不连续性等有关问题进行了讨论。
The relationship between the toughening effect and the reinforcement orientation has been explored for the CMCs with discontinuous elongated reinforcements, including a theoretical model and some examinations with SiC whisker directionally reinforced Si3N4 materials. The results show that the first toughening effect that steeply increases and saturates with small crack extension reduces with the increase of θ, however, when θ= 30°~ 60°, the second toughening effect occurs, showing that the fracture resistance again slowly increases and saturates with larger crack extension. In terms of the theoretical analyses and some experimental appearances, the relationship between the toughening mechanisms and the reinforcement orientation, the effects of the microstructrual parameters and the discontinuity of the toughening process are also discussed.
出处
《高技术通讯》
EI
CAS
CSCD
1997年第4期11-15,共5页
Chinese High Technology Letters
基金
863计划
清华大学新型陶瓷与精细工艺国家重点实验室资助
关键词
不连续细长相
增韧
方位角
二次增韧
Discontinuous elongated reinforcements, Toughening effects, Reinforcement Orientation
