2D-C/SiC复合材料开孔件拉伸强度有限元计算

对2D-C/SiC复合材料开孔试件最小净截面图像进行观测，获得试件材料内部宏观孔洞的分布形态及密度分布梯度。通过对2D-C/SiC复合材料拉伸应力-应变行为进行非线性拟合，并利用理论模型计算与实验验证相结合的方法得到了材料密度与其拉伸模量和强度的关系，描述了不同密度2D-C/SiC复合材料的拉伸应力-应变行为。在此基础上，将制备工艺造成的试件材料密度分布的非均匀性和材料拉伸应力-应变行为的非线性引入到有限元模型中，进行开孔试件拉伸剩余强度模拟计算，预测结果与实验结果吻合较好。

FEM calculation about tensile strength of 2D-C/SiC composites with circular holes

According to the smallest net section's picture of 2D-C/SiC composite laminates with circular hole, the macroscopic pores distribution and the gradient of loco-regional material density inside of specimen were obtained. The tensile stress-strain behavior of 2D-C/SiC composite laminates was fitted by nonlinear curve, and the material density's influence on initial tensile module and tensile strength also was investigated by associating theoretical model simulation with experimental verification. The tensile nonlinear stress-strain behavior of 2D-C/SiC composite with different density were described successfully. The mechanics analytical finite element model was built by taking the material density inhomogeneity in the specimen internal into account, and the material tensile nonlinear stress-strain behavior also varies with its density. The prediction in the net section tensile strength values of open-hole specimen go along well with the experimental results.