Significantly enhancing fracture toughness of epoxy composite with promising γ-FeOOH@Fe2O3 hybrid nanoparticles by magnetic field assistance
Chen Guan, Chuanguo Ma, Zehao Fu, Jing Wang, Peibang Dai
Abstract
The toughening of epoxy resin (EP) and the interlaminar toughening of carbon fiber reinforced composite (CF/EP) laminates have been widely concerned. In this work, the needle-like γ-FeOOH nanoparticles were prepared by liquid phase deposition-air oxidation method, and then were calcined under different conditions to obtain γ-FeOOH and γ-Fe2O3 hybrid nanoparticles (γ[email protected]2O3). Effect of calcination condition of γ[email protected]2O3 and magnetic field assistance on fracture toughness (KIC) of EP was systematically investigated. Then the selected γ[email protected]2O3 with the best toughening effect were used to improve the mode I interlaminar fracture toughness (GIC) of CF/EP laminate. The resulting γ[email protected]2O3 have a length of around 1 μm, a diameter of around 100 nm and the Ms of 8.99–45.96 emu/g. After calcinated at 250 °C for 1 h, the γ[email protected]2O3 containing 24 wt% FeOOH and 76 wt% Fe2O3 achieved the best toughening effect. Under a magnetic field of 0.09 T, the KIC of the γ[email protected]2O3/EP composite (2.45 MPa m1/2) is 81.7% and 66.7% higher than that of neat epoxy and the composite without magnetic field induction, respectively. Furthermore, the GIC of the γ[email protected]2O3/CF/EP composite (0.914 kJ/m2) is also significantly increased by 88.8% and 51.8% compared to that of CF/EP and the corresponding composite without magnetic field induction, respectively.