High strength glass-ceramics having petalite and lithium silicate structures
AssigneeCorning Incorporated
InventorsGeorge Halsey Beall, Qiang Fu, Charlene Marie Smith
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Abstract
Glass and glass ceramic compositions having a combination of lithium silicate and petalite crystalline phases along with methods of making the glass and glass ceramic compositions are described. The compositions are compatible with conventional rolling and float processes, are transparent or translucent, and have high mechanical strength and fracture resistance. Further, the compositions are able to be chemically tempered to even higher strength glass ceramics that are useful as large substrates in multiple applications.
Claims34
A glass-ceramic article comprising:
- a petalite crystalline phase comprising 45 to 70 wt % of the glass-ceramic article;
- a lithium silicate crystalline phase comprising 20 to 50 wt % of the glass ceramic article;
- and
- greater than 10 wt % Li2O,
- wherein the petalite crystalline phase and the lithium silicate crystalline phase have higher weight percentages than other crystalline phases present in the glass-ceramic article.
A method of forming a glass-ceramic article, the method comprises:
- forming a glass composition comprising, in wt %:
- SiO2:
- 55-80%;
- Al2O3:
- 2-20%;
- Li2O:
- greater than 10-20%;
- B2O3:
- 0-12%;
- Na2O:
- 0-5%;
- ZnO:
- 0-10%;
- P2O5:
- 0.5-6%;
- and
- ZrO2:
- 0.2-15%;
- and
- ceramming the glass composition to form a glass-ceramic article comprising a petalite crystalline phase comprising 45 to 70 wt % of the glass-ceramic article and a lithium silicate crystalline phase comprising 20 to 50 wt % of the glass ceramic article, wherein the petalite crystalline phase and the lithium silicate crystalline phase have higher weight percentages than other crystalline phases present in the glass-ceramic article.
A glass-ceramic article comprising:
- a petalite crystalline phase;
- a lithium silicate crystalline phase;
- and
- greater than 10 wt % Li2O,
- wherein the petalite crystalline phase and the lithium silicate crystalline phase have higher weight percentages than other crystalline phases present in the glass-ceramic article, and
- wherein the article is translucent and has a transmittance in a range from 20 to less than 85% for light in a wavelength range from 400 nm to 1,000 nm at a thickness of 1 mm.
Dependencies are inferred from the claim text.