Zirconia-toughened glass ceramics
AssigneeCorning Incorporated
InventorsGeorge Halsey Beall, Qiang Fu, Charlene Marie Smith
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Abstract
ZrO2-toughened glass ceramics having high molar fractions of tetragonal ZrO2 and fracture toughness value of greater than 1.8 MPa·m1/2. The glass ceramic may also include also contain other secondary phases, including lithium silicates, that may be beneficial for toughening or for strengthening through an ion exchange process. Additional second phases may also decrease the coefficient of thermal expansion of the glass ceramic. A method of making such glass ceramics is also provided.
Claims44
A glass ceramic comprising a first crystalline phase comprising a tetragonal ZrO2 phase;
- a second crystalline phase comprising a lithium disilicate, and a residual glass phase,
- wherein the glass ceramic comprises an ion exchanged layer having a depth of compression of at least 10 μm and the glass ceramic has fracture toughness of from 1.8 to 10 MPa·m1/2;
- wherein the glass ceramic further comprises >0-5 mol % TiO2.
A glass ceramic comprising a first crystalline phase comprising a tetragonal ZrO2 phase;
- a second crystalline phase comprising a lithium disilicate, and a residual glass phase,
- wherein the glass ceramic comprises an ion exchanged layer having a depth of compression of at least 10 μm and the glass ceramic has fracture toughness of from 1.8 to 10 MPa·m1/2;
- wherein the glass ceramic further comprises two or more additional crystalline phases,
- wherein the two or more additional crystalline phases comprise a monoclinic ZrO2 phase and a phase selected from the group consisting of lithium aluminosilicate, β-spodumene solid solution, β-quartz solid solution, or α-quartz;
- wherein the monoclinic ZrO2 is from >0-5 wt % of the glass ceramic.
A glass ceramic comprising a first crystalline phase comprising a tetragonal ZrO2 phase;
- a second crystalline phase comprising a lithium disilicate, and a residual glass phase,
- wherein the glass ceramic comprises an ion exchanged layer having a depth of compression of at least 10 μm and the glass ceramic has fracture toughness of from 1.8 to 10 MPa·m1/2;
- wherein the glass ceramic further comprises >0-4 mol % of a color component and 18-40 mol % Li2O, wherein the color component selected from the group consisting of:
- Fe2O3, V2O5, Cr2O3, MnO2, NiO, CuO, Co3O4 and combinations thereof.
Dependencies are inferred from the claim text.