Patent ID: 11926555
Assignee: CORNING INCORPORATED
Field: Materials, metallurgy (Chemistry)
Classification: CPC C  Y | IPC C

Claim 11:
12. A glass-ceramic article comprising:
a composition, in mole %; comprising:
SiO2 in the range from 62 to 75;
Al2O3 in the range from 10.5 to 17;
Li2O in the range from 5 to 13;
ZnO in the range from 0 to 4;
MgO n the range from 0 to 8;
B2O3 in the range from 0 to 4;
Na2O in the range from 0 to 5;
K2O in the range from 0 to 4;
ZrO2 in the range from 0 to 2;
P2O5 in the range from 0 to 7;
Fe2O3 in the range from 0 to 0.3;
MnOx in the range from 0 to 2;
a ratio [Li2O+Na2O+K2O+MgO+ZnO]/[Al2O3+B2O3]
in the range from 0.7 to 1.5;

a crystalline phase; wherein the crystalline phase comprises β-spodumene and cordierite; and
a Vickers crack initiation threshold of at least 12 kgf,
wherein the glass-ceramic article further comprises a compressive stress of at least 300 MPa.