Composition and structural evolution of basalt melt during homogenization

Abstract During fabrication of basalt fiber, one critical procedure is the homogenization of melt, which typically lasts over 10 h at ∼1500°C. However, the changes in composition and structure of basalt melt during the homogenization process remain poorly understood. In this study, basalt melts were held at 1550°C for various durations and then rapidly quenched to form basalt glasses, enabling analyses of their compositional and structural evolution. Compositions of glasses were analyzed using chemical titration, energy dispersive X‐ray, and inductively coupled plasma optical emission spectrometry methods. The crystallization process was examined through differential scanning calorimetry analysis, while structural evolution was investigated via Raman and X‐ray photoelectron spectroscopy O1s spectroscopy. The results showed that the primary composition change during homogenization was the valence transition from Fe 3+ to Fe 2+ . The O 2‐ produced with the valence transition gradually converted the Q 3 units into the Q 2 units. The homogenization process reached the stability of composition and structure after 8 h. A high proportion of Q 2 units will align along the fiber axis, enhancing the melt spinnability and reinforcing the basalt fiber.