METHOD FOR DETERMINING GLASS VISCOSITY Russian patent published in 2023 - IPC G01N11/00 

FIELD: monitoring properties of glass.

SUBSTANCE: invention relates to methods for monitoring the thermophysical properties of glass and, in particular, to determining the dependence of the change in viscosity on temperature. The method for determining the viscosity of glass includes testing with a glass sample by tensile deformation in heated to a state of glass viscosity value corresponding to 9>lg(η)>5, and calculating the absolute value of the viscosity at a fixed temperature by molding a flat glass sheet into a cone shape, under a constant vacuum load in the cone shape, at a constant heating rate in the temperature range corresponding to the logarithm of the viscosity 9>lg(η)>5. Throughout the molding process, the change in the tensile strain of the glass sample into a cone shape and the temperature corresponding to this change in deformation are recorded, with further plotting of the graphical dependence of the strain change on the temperature change and comparing the graphical dependence of the tested glass sample with the graphical dependence constructed as a result of testing the reference glass sample, carried out earlier under the same conditions. The relative deviation of the value of the tensile strain of a flat sheet into a conical shape of the test and reference samples determines the relative change in the logarithm of the viscosity of the glass of the test sample from the logarithm of the viscosity of the glass of the reference sample, which determines the value of the viscosity of the test glass at temperatures corresponding to the range 9>lg(η)>5.

EFFECT: increase in the reliability of the dependence of viscosity on temperature.

1 cl, 7 dwg, 8 tbl