Structural characterization and mechanical properties of basalt-based glasses and fibers with Fe2O3 addition

• Fe₂O₃ content tunes basalt fiber drawing temperature and properties. • Maximum fiber strength of 2645 MPa is achieved at 2 wt% Fe₂O₃. • Glass functional properties are tailored via composition. • A structure-property relationship from melt to fiber is established. This study systematically investigates the impact of Fe₂O₃ addition on the structure and properties of basalt-based glasses and fibers prepared from SDZB-2008 raw material. The results indicate that increasing Fe₂O₃ content significantly lowers the maximum fiber drawing temperature and enhances the melt’s crystallization tendency, while generally reducing the overall crystallinity. A non-linear evolution in functional properties is observed, with saturation magnetization reaching a maximum of 1 emu/mg and the dielectric constant attaining a minimum of 6.24. In terms of mechanical performance, fiber strength shows a non-monotonic dependence on Fe₂O₃ content, achieving a maximum strength of 2645 MPa with 2% Fe₂O₃ addition, while fiber diameter decreases consistently. These findings demonstrate the strong potential of Fe₂O₃-modified basalt fibers for use in construction materials as reinforcement elements, in aerospace-grade composite structures requiring high specific strength, and in functional applications where tailored dielectric or magnetic properties are critical. The study provides valuable insights for optimizing basalt-based materials towards specific engineering applications.