Experimental and numerical studies on the tensile behaviors of thin-ply and thick-ply open-hole laminates

• Published in: Thin-walled structures 2023-05, Vol.186, p.110649, Article 110649
• Main Authors: Zheng, Kaidong, Hu, Haixiao, Cao, Dongfeng, Zhong, Yucheng, Li, Shuxin
• Format: Article
• Language: English
• Subjects: Damage evolution; Damage morphologies; Drilling-induced delamination; LaRC; Open-hole laminates
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/j.tws.2023.110649

Laminated composites with thin-ply unidirectional prepregs are popular due to their higher in-situ strength as compared with thick-ply laminates due to different failure mechanisms. Thin-ply and thick-ply open-hole laminates were fabricated and the tensile failure characteristics were studied by combining experimental and numerical simulation approaches. Charge-coupled device camera and de-ply technology were used to obtain failure morphologies of open-hole specimens under tensile loading. A finite element model considering progressive damage and bilinear cohesive model was built based on ABAQUS to study the damage mechanism of open-hole laminates. In thin-ply laminates, the damage plane was relatively neat while in thick-ply laminate broom-shaped damage morphologies were observed. Based on de-ply experiments and numerical prediction, it was found that thin-ply laminates had delamination suppression effect and could restrain the propagation of delamination along the loading direction, which explains the distinct damage patterns existed in thin-ply and thick-ply laminates. Based on numerical prediction, it was found that drilling-induced delamination did not affect the tensile strength of open-hole laminates. Propagation of drilling-induced delamination was also restrained in thin-ply laminates. The results of this research suggested that thin-ply prepregs should be considered when delamination poses critical threat to the structural integrity of laminated composite structures. •A progressive damage model considering LaRC 05 failure criterion is proposed and implemented via an in-house VUMAT code.•Damage evolution of open-hole laminates fabricated using thin-ply prepregs under tensile loading is studied.•Advantages of thin-ply laminates and underlying mechanisms are studied and proved.•Effects of drilling-induced delamination on the mechanical properties of laminated composites are discussed.