High-strength basalt/carbon fiber reinforced polymer via constructing PVDF-fiber veils

To improve interfacial condition and mechanical properties of basalt/carbon fiber reinforced polymer (BCFRP) laminates, this study innovatively employed a double electrospinning technique to prepare multi-directional polyvinylidene fluoride (PVDF) fiber veils on carbon fiber (CF) fabric surfaces. Energy-dispersive X-ray spectrometer (EDS) confirmed the uniform distribution of fluorine, verifying the successful anchoring of PVDF onto the CF fabric. With systematically varied areal densities (0.1-0.5 g/m²), the PVDF veils demonstrated a substantial enhancement in mechanical performance, with the 0.4 g/m² density identified as optimal. This specific formulation yielded remarkable flexural and compressive strengths of 529.26 MPa and 248.08 MPa, corresponding to significant improvements of 37.9% and 43.6%, respectively, over the unreinforced specimen. Microstructural analysis via X-ray microscopy (XRM-CT) and scanning electron microscopy (SEM) revealed that the multi-directional PVDF veils established continuous fiber bridges at the interlaminar interface. These bridges provided a better fracture resistance to prevent the generation and propagation of micro-cracks, promoting failure mode variation from traditional dominated delamination to shear-dominated failure. This work established a novel technical pathway for developing high-performance PVDF@BCFRP laminates, presenting a viable alternative to traditional CFRP composites for civil applications.