Degradation of basalt fibre and glass fibre/epoxy resin composites in seawater

Epoxy resins reinforced, respectively, by basalt fibres and glass fibres were treated with a seawater solution for different periods of time. Both the mass gain ratio and the strength maintenance ratio of the composites were examined after the treatment. The fracture surfaces were characterized using scanning electron microscopy. The tensile and bending strengths of the seawater treated samples showed a decreasing trend with treating time. In general, the anti-seawater corrosion property of the basalt fibre reinforced composites was almost the same as that of the glass fibre reinforced ones. Based on the experimental results, possible corrosion mechanisms were explored, indicating that an effective lowering of the Fe2+ content in the basalt fibre could lead to a higher stability for the basalt fibre reinforced composites in a seawater environment.

Research highlights
► BFRP degradation process in seawater environment was first investigated.
► The mass gain change includes two effects: absorption and extraction.
► The interfacial adhesion of BFRP is bigger than GFRP.
► After treated, the bending strength of BFRP is lower than GFRP.
► Reducing the Fe2+ in the basalt fibre could lead to a higher stability of BFRP.