The Viscosity and Working Characteristics of Glasses. Part I.-The Viscosity of Some Commercial Glasses at Temperatures Between Approximately 500° and 1400°.
JSGT 1942 V26 T215-T240
As the preliminary to a systematic review of the relationship between the viscosity of a mass of glass (or, more strictly, between the viscosity at different points of the mass) undergoing manipulation by hand or machine and the temperature ranges between which the various stages of manipulation can be satisfactorily carried out, the viscosities of twenty four glasses, three of them synthesised from pure materials and twenty one of different types employed commercially, have been determined by two precision methods, the Margules method for temperatures from approximately 750° to 1400°, and by a fibre extension method for temperatures from approximately 500° to 800°. From the results, combined with such trustworthy data as have been obtained by other workers, factors have been derived for the oxides SiO2,Al2O3, Fe2O3, CaO, MgO, NaO, and PbO by which, within prescribed limits of composition, the viscosities of glasses containing them can be calculated.
James Boow, B.Sc.Tech., Ph.D., and Professor W. E. S. Turner
