Analysis of Low Temperature Viscosity Data for Three NBS Standard Glasses

Area of Science:

• Materials Science
• Physical Chemistry
• Glass Science

Background:

• Viscosity standards are crucial for calibrating measurements in materials science.
• Accurate viscosity data at low temperatures is essential for understanding glass behavior.

Purpose of the Study:

• To report precise low-temperature viscosity measurements for three National Bureau of Standards (NBS) viscosity standard glasses.
• To compare the precision of fiber-elongation and beam-bending methods for viscosity determination.
• To investigate the temperature dependence of viscosity and its adherence to theoretical models.

Main Methods:

• Viscosity measurements were conducted using both fiber-elongation and beam-bending techniques.
• Data collection spanned a wide viscosity range, from 10^9 to 10^16 poise.
• The Fulcher Equation was employed to analyze the viscosity data and associated uncertainties.

Main Results:

• Extensive viscosity data were obtained for three standard glasses, overlapping with existing certificate values.
• No evidence of Arrhenius behavior was observed in the viscosity of the tested glasses.
• Fiber-elongation measurements demonstrated higher precision compared to beam-bending measurements.

Conclusions:

• The study provides reliable low-temperature viscosity data for NBS standard glasses.
• The findings highlight the superior precision of the fiber-elongation method for high-viscosity measurements.
• The Fulcher Equation effectively models the viscosity-temperature relationship and associated uncertainties for these glasses.