论文部分内容阅读
利用扫描电子显微镜(SEM)对不同纤维方位角的玻纤增强树脂复合材料(GFRP)在单拉载荷下的破坏过程进行了实时观测.在桥联模型基础上,将纤维剪应力和基体正应力定义为界面的应力状态,对概化的GFRP材料单元进行了定量分析,得到了单拉载荷下纤维体积分数为27.5%的单元起裂时的应力状态,并通过最大应力强度准则确定了导致起裂的应力分量.综合SEM图片中裂纹形态和断口形貌,分析了不同纤维方位角的GFRP材料裂纹萌生和裂纹扩展的机理.分析结果表明,随着纤维方位角增大,导致GFRP材料裂纹萌生的应力分量由基体最大主应力演化为界面剪应力;裂纹扩展路径由最大主应力控制的基体开裂演化为最大剪应力控制的界面开裂.
Scanning electron microscope (SEM) was used to observe the failure process of glass fiber reinforced plastic composites (GFRP) with different fiber azimuths under single tension load.Based on the bridge model, the fiber shear stress and matrix normal stress Is defined as the interface state of stress. Based on the quantitative analysis of the generalized GFRP material elements, the stress state of the cell with the fiber volume fraction of 27.5% under single-tension loading is obtained, and the maximum stress intensity criterion The crack initiation and crack propagation of GFRP materials with different fiber azimuth angles were analyzed based on the crack morphology and fracture morphology of the SEM images.The results show that as the fiber azimuth angle increases, the crack initiation of GFRP material The stress component evolves from the maximum principal stress of the matrix to the interfacial shear stress. The crack propagation path evolves from the cracking of the matrix controlled by the maximum principal stress to the interface cracking controlled by the maximum shear stress.