摘要
依据四向编织炭/炭复合材料的结构特点,建立了能反映其编织方式和空间构型的单元体胞模型。在单胞几何模型和介观计算力学基础上,采用有限元方法研究了在不同石墨化温度、降温梯度和界面刚度情况下四向编织炭/炭复合材料的残余热应力分布。研究表明:低温石墨化复合材料的残余热应力比高温石墨化时小。界面刚强度低时石墨化过程中残余热应力比界面刚强度高时小。冷却速率越快,残余热应力越大。
A representative volume element model was proposed for C/C composites with the fibers oriented in four different directions.Three of the fiber directions were coplanar,at 120° to each other,and the fourth was perpendicular.The element truly reflects the orientations of the carbon fibers and matches the actual configuration of the composites.Based on the model and computational mesoscopic mechanics,the residual thermal stress distribution of the material at different graphitization temperatures,cooling rates,and interface stiffnesses was obtained using a finite element method.The residual thermal stresses of the composite from a low-graphitization temperature or with low interface stiffness are lower than those from a high-graphitization temperature or with high interface stiffness.The higher the cooling rate,the higher the residual thermal stress.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2011年第4期287-292,共6页
New Carbon Materials
关键词
炭/炭复合材料
石墨化温度
降温梯度
Carbon/carbon composite
Graphitization temperature
Cooling grads
