Open AccessOpen hole size effects on tensile properties of 3D braided composites
Author(s) -
Shuangqiang Liang,
Qing Zhou,
Ge Chen
Publication year - 2021
Publication title -
industria textilă
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.281
H-Index - 14
ISSN - 1222-5347
DOI - 10.35530/it.072.05.202010
Subject(s) - braid , materials science , composite material , ultimate tensile strength , delamination (geology) , residual strength , composite laminates , modulus , composite number , paleontology , biology , subduction , tectonics
Owing to the excellent integrated structure, notch-insensitivity, delamination-free characteristics, 3D braided compositeshave a broad range of engineering applications. In this paper, the notch size effects on two types of 3D braidedcomposites were experimentally examined. Style I incorporated 40% of longitudinal lay-in yarns. Style II was the purebraids. The Point Stress Criterion (PSC) was applied to predict the open-hole strength of 3D braided composites. It isfound the 3D braided composites can keep higher proportion residual strength after involving the different circular holesizes compared to plain woven laminates. The open-hole pure braided specimen shows better performance than thatthe braids with longitudinal yarns, the lay-in longitudinal yarns improve neither specimens’ un-notched strength, nor themodulus. The predicted open-hole strength were compared with experimental results. The traditional analytical methodcan predict the open-hole strength of 3D braided composite to some extent. Under uniaxial tensile stress, the failurebehaviour of two types of 3D braided specimens are different. For un-notched specimen, clear cracks usually show upon the Style II specimen, while it is not true for Style I coupon. For notched specimen, the crack of both notchedspecimens will propagate along the notch and finally render the specimen to fail