拉伸载荷下碳纤维/环氧树脂织物层合板疲劳断裂特性  

Fatigue Fracture Characteristic of Carbon Fiber/Epoxy Fabric Laminates under Tensile Loading

作　　者：汪莹 刘逸众[1] 李桃山 聂明明 WANG Ying;LIU Yizhong;LI Taoshan;NIE Mingming(Airforce Aviation Repair Institute of Technology,Changsha 410124,China;Changsha 5712 Aircraft Industry Co.,Ltd.,Changsha Hunan 410113,China)

机构地区：[1]空军航空维修技术学院,湖南长沙410124 [2]长沙五七一二飞机工业有限责任公司,湖南长沙410113

出　　处：《塑料工业》2024年第9期104-111,161,共9页China Plastics Industry

基　　金：湖南省教育厅科学研究项目(23C1054);湖南省自然科学基金科教联合基金项目(2020JJ7078)。

摘　　要：为探究纤维增强树脂基复合材料疲劳寿命预测和损伤演化问题,通过复合材料层合板拉伸和疲劳实验,获得了4种不同循环应力下碳纤维/环氧基平纹织物层合板的疲劳数据,并以此建立了一种织物层合板的疲劳模型。采用有限元方法分析了层合板的失效过程和性能退化,模拟了织物层合板的疲劳寿命和损伤扩展过程。利用超声波C扫、超景深显微镜和扫描电子显微镜观察疲劳断口形貌及内部损伤,并与仿真结果对比,研究了纤维增强复合材料疲劳损伤演化和断裂机理。结果表明,复合材料层合板疲劳损伤演化主要分3个阶段。在疲劳初期,层合板两侧边表面最先出现层内分层和基体裂纹;中期损伤扩展加快,损伤形式主要以层间损伤为主;末期层合板内严重分层,裂纹趋于饱和,大量纤维断裂,性能迅速退化;最后,损伤贯穿整个横面,发生疲劳断裂。To study the fatigue life prediction and damage evolution of fiber-reinforced resin matrix composites,the tensile and fatigue tests were conducted on composite laminates.A fatigue life model for fabric laminates was established based on the fatigue data of carbon fiber/epoxy plain woven fabric laminates under four different cyclic stresses.The failure process and degradation of laminates properties were analyzed by using the finite element method,the fatigue life and damage propagation process of fabric laminates were calculated and simulated.The fatigue fracture morphologies and internal damages were observed by using ultrasonic C-scan,ultra-depth microscope,and scanning electron microscope.The fatigue damage evolution and fracture mechanism of fiber-reinforced composite materials were discussed by comparing with the simulation results.The results indicate that the fatigue damage evolution of composite laminates exhibits three obvious stages.In the early stage of fatigue,the in-layer delamination and matrix cracks first appear on both sides of the laminates.The damage propagation accelerates at the middle stage,and the main damage form is the interlayer damage.In the late stage,the delamination is severe in the laminates,cracks tend to be saturated,a large number of fibers fracture,the performances of laminates deteriorate rapidly.Finally,the damages penetrate the entire cross-section and the fatigue fracture occurs.

关 键 词：碳纤维 环氧树脂 有限元 疲劳断裂 损伤演化 

分 类 号：TQ323.5[化学工程—合成树脂塑料工业]