Improved energy absorption of 3D orthogonal woven glass fiber composites with flax yarn hybridization

Three-dimensional (3D) orthogonal woven composites based on glass fibers are attractive for load-bearing applications owing to their high stiffness and structural integrity, but their intrinsically brittle failure behavior limits deformation capability and energy absorption. In this work, a 3D orthogonal glass/flax hybrid composite (3DOHC) was developed by partially replacing glass yarns with flax yarns in the warp and weft directions. The compressive and bending behaviors of the hybrid composite were systematically investigated and compared with those of a conventional 3D orthogonal glass fiber composite (3DOGC). The results show that the incorporation of flax yarns leads to a significant reduction in density, while markedly improving energy absorption capability under both compressive and bending loads. Microstructural observations reveal a transition from brittle-dominated failure in 3DOGC to progressive deformation-controlled failure in 3DOHC, associated with plastic deformation of flax fibers and delayed crack propagation. These findings demonstrate that flax yarn hybridization provides an effective strategy to improve the damage tolerance and energy absorption capability of 3D orthogonal woven composites under compressive and bending loading.