A TiO2-SiO2 glass ingot was fabricated by the soot method and homogenized by the zone-melting method. Elastic homogeneities of specimens prepared at different production stages were evaluated by measuring leaky surface acoustic wave (LSAW) velocity VLSAW using the line-focus-beam ultrasonic material-characterization system at 225MHz. The homogeneous VLSAw distribution was within ±1.13m/s, corresponding to a variation of the coefficient of thermal expansion (CTE) of ±5 ppb/K, and no striae were observed. VLSAW changes associated with residual stress inside the ingot could be detected. The relationships among V LSAW, TiO2 concentration, density, CTE characteristics, and fictive temperature were investigated. We found the possibility for extremely homogeneous TiO2-SiO2 glass with zero-crossing in CTE at a desired room temperature.
ASJC Scopus subject areas
- Physics and Astronomy(all)