Thermal and optical properties of glasses of the system Bi₂O₃ – B₂O₃

Abstract

In the binary system Bi 2 O 3 -B 2 O 3 glasses were prepared in the composition range 57.5 mol% -80 mol% B 2 O 3 by defined slow cooling of large melt samples (about 75 cm 3 , each). Temperatures of crystallization, of melting and of glass transition were determined and density data of the glasses were derived using the hydrostatic weighting method. Thermal expansion coefficients and high precision refractive indices, together with their dispersion, were measured. The measured physical properties indicate subtle discontinuous structural changes of the glasses with glass composition, that match with the ranges of existence of the crystalline compounds of the binary system Bi 2 O 3 -B 2 O 3 . Thermal investigations together with X-ray powder diffraction analyses of crystallized glass samples prove the so far doubtful existence of a borate compound named "BiBO 3 " in the PDF within the composition range 52.5 -57.5 mol% B 2 O 3 .

Review of Bi2O3 based glasses for electronics and related applications

“…110,317,318,326 Except the oldest study, 110 they agree on a practical stability optimum near 45% BiO 1?5 , in agreement with the break in the liquidus temperature (Fig. 2), versus falling T g (Fig.…”

“…It is nevertheless possible to achieve apparently homogeneous vitrification throughout this range if quenching sufficiently fast from above the gap. 110 For the 'strict' Bi 2 O 3 -B 2 O 3 binary, the extensive and well controlled work of Becker 317 (very large melts, controlled cooling, noble metal crucibles, 20-43%Bi 2 O 3 ) is deemed the most reliable for slow cooling. At intermediate cooling rates, the maximum Bi content is y60%, 118,244,318 with 66% achievable for splat quenching.…”

Raman studies and optical properties of some (PbO)x(Bi2O3)0.2(B2O3)0.8−x glasses

“…Hence, vitreous B 2 O 3 possesses a two-dimensional (2D) sheet-like arrangement with weak intermolecular (intersheet) interaction and with low glass transition temperature (³260°C). 23 The Raman spectra of B 2 O 3 24 consist of one sharp peak at around 810 cm 1 due to symmetric stretching of oxygen in the boroxol ring, a weak peak at around 450 cm 1 attributed to symmetric stretching of the bridging oxygen shared by two boroxol ring and a weak peak at around 1260 cm 1 indicating the possible continuous random network arrangement of boroxol rings. 25 The incorporation of the heavy-metal oxide (HMO) Bi 2 O 3 (x D 0, Table 1) has drastically changed the glass properties: the molar volume decreased, the glass transition temperature increased and Raman spectra changed significantly.…”

Periodic sub-wavelength structures with large phase retardation fabricated by glass nanoimprint

“…It is expected that Bi2O3-GeO2-B2O3 glass fulfills the properties required in the present study, since it is known that Bi2O3-B2O3 glasses have a high refractive index and low deformation temperature 18) and it is expected from the optical basicity that the addition of GeO2 to Bi2O3-B2O3 glass improves the transmittance in the near ultraviolet ray region. 19) Therefore, the glass formation and properties of glass were studied in Bi2O3-GeO2-B2O3 system, particularly, in the composition of (40 -0.5y)Bi2O3·yGeO2·(60 -0.5y)B2O3 along the compositional line between 40Bi2O3·60B2O3 and 80GeO2·20B2O3.…”