An evaluation of the loading direction sensitivity of 3D woven composite with novel web-shaped Z-binder architecture

Abstract 3D orthogonal (ORT) through-thickness woven composites have excellent out-of-plane properties but exhibit inferior in-plane properties and are loading sensitive. This study proposes a novel web-shaped orientation of z-binder architecture in 3D orthogonal through-thickness model with in-plane uniform elastic moduli to address this drawback. On-axis tensile, Off-axis tensile and In-plane Shear tests were performed on the four macroscale models (ORTon, WEBon, ORToff, WEBoff). The ORT model, validated by data from the literature, was used as a reference for the proposed WEB model. The overall fibre volume fraction of the WEBon, and WEBoff models were 7.07% and 8.67% lower than the ORTon, and ORToff models. In the on-axis tensile test, the Ex and Ey were lower by 16.89% and 2.66% for WEBon model, but in the off-axis tensile test, they were higher by 13.75% and 13.77% for WEBoff models. The Gxy was 10.96% lower for WEBon model. The difference between the Ex and Ey under on-axis loading conditions was 14.81% for ORT model, whereas 0.22% for WEB model. Thus, the proposed WEB shaped z-binder architecture model outperforms the ORT model under the off-axis and is comparable in transverse loading conditions. It also possesses loading direction insensitivity, unlike the ORT model.