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The failure mode is a dominant factor of mechanical performance of braided composite tube subjected to axial compression. The failure mode was modified by tailoring stack-up sequence of composite tubes hybridized by bi/tri-axial braided laminate. The thermal photographing and micro-CT scanning methods were employed to monitor the in-situ damage progression and post-mortem specimen, respectively. The results show that the delamination was easy to be induced at the interface nearby tri-axial braided laminate. It attributes to the combination between the crack caused by local buckling of the axial yarns and the crack caused by shear deformation of braiding yarns. By the illumination of this behavior, delamination is controlled to occur at the different position along thickness direction of braided tube by adjusting the stacking sequence of braided laminates. When delamination position transfer from the inner/outer sides to the middle of tube wall, the failure mode transfer from the progressive folding to splaying, which increase the specific energy absorption by 45.77%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Integral braiding and near-net forming of CFRP and CFRP/Al hybrid composite tubes. • In-situ and real-time failure mode analysis of CFRP and CFRP/Al composite tube under transverse impact. • Comprehensive effect of braiding angle, locailzed temperature rise, and ductile aluminum on the damage mechanism. High-speed infrared thermography, micro-CT characterization and full-scale mesostructural simulation were jointly applied to reveal the impact deformation and damage mechanism of composite tubes. Two different failure modes, namely the Impact Side Dominated (ISD) and Impact-/Non-impact Side (INIS), were found to have relation with the braiding angle and localized temperature rise. The hybrid effect can not only prevent resin fragmentation in the triangle region at the lateral side and the diamond region at the non-impact side, but also inhibit the CFRP damage development at the lateral and non-impact side. In small-angle braided tube, the impact-side rebound trend of CFRP layer leads to mismatch at the CFRP-Al interface, which results in opening delamination. In large-angle braided tube, the non-impact-side damage plays an important role in further load-bearing capacity. Apart from the structure effect, temperature rise has an effect on composite damage mode by degrading the localized matrix stiffness. [ABSTRACT FROM AUTHOR]