Tensile Properties of Z-pins Reinforced Laminates

The delamination toughness of Z-pins reinforced laminates could be improved significantly and in-plane mechanical properties of the laminates were degraded with a few of Z-pins inserted in the through-thickness direction. The influence of Z-pin inserted parameters and moisture absorption condition on the tensile properties of the laminates was experimentally studied. The results showed that Z-pins can change microstructure and the original stress-strain state of the Z-pinned laminates, and the tensile strength and modulus of the laminates were obviously influenced. The tensile modulus of the Z-pinned laminates decreased with the increasing of Z-pins’ diameter and volume content, while it increased with that of Z-pins’ angle. The moisture absorption rate and balanced moisture content of Z-pinned laminates increased due to Z-pin inserted, which eventually resulted in accelerating degradation of performance of composites laminates.