Cross-scale investigation into the regulation of basalt melt structure evolution and fiber forming performance via Y2O3 doping

This study integrated multi-scale characterization techniques with molecular dynamics simulations to systematically investigate the regulatory mechanism by which Y₂O₃ doping influences the structural evolution of basalt melt and its fiber formability. The stability of the melt structure was optimized by adjusting the addition amount of Y₂O₃. The results show that Y₂O₃ with a dosage of 1 wt% significantly reduces the liquid phase temperature of the system, enhances the uniformity of the melt, and lowers the brittleness index. The spinnable temperature range is broadened, with the maximum spinnable temperature reaching a range of 80 °C. The fiber exhibits an average diameter of 10.41 μm and a tensile strength of up to 2099 MPa. Fourier infrared spectroscopy (FTIR) analysis reveals that the degree of polymerization of the glass network initially increases and subsequently decreases with increasing Y₂O₃ content. X-ray photoelectron spectrometer (XPS) results confirm that Y³⁺ repairs structural defects in the melt through the formation of Y-O-Si bonds. Molecular dynamics simulations further reveal that the doping concentration of Y³⁺ induces dynamic coordination reconstruction of aluminum-oxygen polyhedra. The incorporation of a small amount of Y³⁺ promotes the transformation of Al from [AlO₆] to [AlO₄] coordination, thereby increasing the BO content and strengthening the melt network structure. This finding provides a theoretical foundation for expanding the drawing temperature window in basalt fiber preparation and improving the fiber's tensile strength.