摘要
开展大厚度L形复合材料层合板残余应变监测和失效行为研究,探究大厚度条件下铺层顺序对结构承载能力和失效模式的影响。采用内埋光纤布拉格光栅(Fiber Bragg Grating,FBG)监测固化成型过程中L形复合材料层合板弧形区域内部的温度场和应变场的演化和分布特征,研究厚度和铺层角度对L形复合材料热残余应变和回弹角的影响。开展侧弯加载试验,借助数字图像相关(Digital Image Correlation,DIC)表征手段观测其侧向截面的应变场和失效模式。与经验公式的结果进行对比研究,探求不同铺层角度条件下热残余应力对大厚度L形复合材料层合板承载能力与失效模式的影响。结果表明:大厚度L形构件存在一定的温度梯度,但上下层与中间层的温差较小;由于模具作用,含角度L形构件比单向铺层结构更易在拐角内侧产生前负载区域。侧弯试验结果表明,纯0°铺层得到的极限载荷和理论预测基本一致,但准各向同性铺层对应的极限载荷比理论预测小25%,说明前负载区对后继承载能力和失效模式会产生一定的影响。
The study involves monitoring residual strains and investigating failure behavior in thick L-shaped composite laminates.It aims to explore how the stacking sequence under high thickness conditions affects the structural load-bearing capacity and failure modes.Utilizing embedded fiber bragg grating(FBG),the study monitors the evolution and distribution characteristics of the temperature field and strain field within the curved region of the L-shaped composite laminate during the curing process.It aims to investigate how thickness and ply orientation angle influence the thermal residual strain and spring-in angle in L-shaped composite laminates.Conducting bending tests,utilizing DIC(digital image correlation)to observe the strain field and failure modes in the lateral cross-section.And comparing the results with empirical formulas,exploring the influence of thermal residual stress under different ply orientations on the load-carrying capacity and failure modes.The results indicate that the large-thickness L-shaped laminates exhibit a certain temperature gradient,but the temperature difference between the upper and lower layers and the middle layer is relatively small.Due to the mold effect,L-shaped laminates with angles are more likely to generate pre-loaded regions on the inner side of the corner compared to pure 0°ply.The results of the bending test indicate that the ultimate load obtained for pure 0°ply is essentially consistent with the theoretical prediction.However,for quasi-isotropic ply,the ultimate load is 25%smaller than the theoretical prediction.The preload region has a certain influence on the subsequent load-carrying capacity and failure mode.
作者
王伟伦
曹子荷
俞星辰
卢弈先
曹东风
胡海晓
冀运东
李书欣
WANG Weilun;CAO Zihe;YU Xingchen;LU Yixian;CAO Dongfeng;HU Haixiao;JI Yundong;LI Shuxin(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China;Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory,Foshan 528200,China;Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics,Wuhan University of Technology,Wuhan 430070,China)
出处
《复合材料科学与工程》
北大核心
2025年第4期1-10,46,共11页
Composites Science and Engineering
基金
国家自然科学基金(52273080,12302481,12172265)
湖北省自然科学基金(20231j0223)
2023年湖北省重大攻关项目(JD2023BAA028)。
关键词
L形复合材料
固化监测
前负载
失效模式
残余应力
L-shaped composite
curing monitoring
pre-loaded
failure mode
residual stress
