Viscosity Measurements Of Glass Melts - Certification Of Reference Materials

This paper describes the investigation and the results for three glass types for qualification as reference materials. The measurements were carried out by means of a specially designed rotational viscometer in a temperature range from 400 up to 1400 deg C. Further measurements were performed in a fibre elongation viscometer to compare elongational viscosity and shear viscosity by means of the Trouton ratio. The viscosity-temperature relationship is presented, the uncertainty of the measurements and the best-fit polynomial equation are calculated and the results discussed.