US 11,834,363 B2
Methods for ceramming glass with nucleation and growth density and viscosity changes
Carol Ann Click, Corning, NY (US); Indrajit Dutta, Horseheads, NY (US); Ozgur Gulbiten, Painted Post, NY (US); Jill Marie Hall, Elmira, NY (US); Mathieu Gerard Jacques Hubert, Corning, NY (US); Andrew Peter Kittleson, Honeoye Falls, NY (US); Rohit Rai, Painted Post, NY (US); John Robert Saltzer, Jr., Beaver Dams, NY (US); Matthew Daniel Trosa, Horseheads, NY (US); and Zheming Zheng, Horseheads, NY (US)
Assigned to CORNING INCORPORATED, Corning, NY (US)
Filed by CORNING INCORPORATED, Corning, NY (US)
Filed on Jul. 15, 2019, as Appl. No. 16/511,171.
Claims priority of provisional application 62/769,253, filed on Nov. 19, 2018.
Claims priority of provisional application 62/698,623, filed on Jul. 16, 2018.
Prior Publication US 2020/0017395 A1, Jan. 16, 2020
Int. Cl. C03B 32/02 (2006.01)
CPC C03B 32/02 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method for ceramming a glass article to a glass-ceramic comprising:
placing a glass article into a heating space of a heating apparatus, the heating space having thermal uniformity throughout the heating space;
heating the glass article within the heating space to a first hold temperature at a first predetermined heating rate;
increasing or decreasing a temperature of the glass article within the heating space relative to the first hold temperature for a first predetermined duration by varying a heating space temperature, wherein viscosity of the glass article is maintained within log of viscosity ±1.0 poise of a target viscosity during the first predetermined duration, wherein the target viscosity is a constant;
heating the glass article within the heating space from the first hold temperature to a second hold temperature at a second predetermined heating rate;
holding the glass article at the second hold temperature for a second duration within the heating space, wherein density of the glass article is measured in-situ from the heating of the glass article from the first hold temperature through the second duration; and
ending the second duration when an absolute value of a density rate of change of the glass article within the heating space is less than or equal to 0.10 (g/cm3)/min.