Bending response and failure mechanism of composite sandwich panel with Y-frame core

The hot-press molding technique was developed to fabricate the Y-frame sandwich core from carbon fiber reinforced polymer composite. The three-point bending tests were conducted to investigate mechanical behavior of the Y-frame sandwich core. The effects of the relative density on the mechanical behavior of the Y-frame sandwich core were revealed by the experiments. The bending load-displacement curves were recorded, which indicated that the bending properties of the Y-frame sandwich core were strongly influenced by the relative density. The bending failure load and the value of P/δ were analytically predicted. The discrepancy between the experimental results and the predictions was analyzed. Furthermore, the analytical prediction also revealed that the value of P/δ was dependent on the span length of the composite Y-frame sandwich core. •The manufacturing process of the composite Y-frame sandwich core was presented.•The failure modes and bending load-displacement curves were recorded.•The effects of relative density on the bending behavior of the composite Y-frame sandwich core was investigated by experiments.•The analytical model was derived to predict the bending properties of the Y-frame sandwich core. Analytical predictions were compared with experimental results.