Coated glass-based assembly
A glass-based assembly includes a glass or glass-ceramic substrate comprising a surface. The surface has flaws, such as a population of small cracks extending into the surface, whereby the substrate is weakened relative to ideal strength thereof. The assembly further includes a coating coupled to the substrate and overlaying at least some of the flaws. Ultimate strength of the substrate with the coating coupled thereto is greater than that of the substrate alone, without the coating.
1 . A glass-based assembly, comprising:
a glass substrate comprising a surface, wherein the surface comprises a crack that extends into the surface, wherein the crack has a depth of at least 50 nm but less than 10 μm,
wherein the glass substrate if uncoated has a first flexural strength;
a coating coupled to the substrate and overlaying at least a portion of surfaces thereof and the crack, wherein the coating comprises a metal oxide,
wherein the coating has a modulus of elasticity of at least 50 GPa;
wherein glass of the glass substrate has a crack-onset strain, and wherein stretching of the coating to the crack-onset strain of the glass does not fracture the coating;
wherein flexural strength of the coated glass substrate is a second flexural strength that is greater than the first flexural strength,
wherein the first flexural strength is less than 500 MPa, and
wherein the second flexural strength is at least 100 MPa greater than the first flexural strength.
2 . The glass-based assembly of claim 1 , wherein glass of the glass substrate having a refractive index of 1.9 or greater at 589 nm.
3 . The glass-based assembly of claim 1 , wherein the glass substrate if uncoated has a failure strain within a range of 0.3% to 1.5%, wherein the glass substrate comprises a modulus of elasticity greater than 90 GPa; and wherein the coating has a crack onset strain within a range of 0.4% to 2.0%.
4 . A glass-based assembly, comprising:
a glass substrate comprising a surface, wherein the surface comprises a crack that extends into the surface,
wherein the crack has a depth of at least 50 nm but less than 10 μm;
wherein the glass comprises less than 40 mol % silica;
wherein the glass substrate if uncoated has a first flexural strength, and wherein the first flexural strength is less than 500 MPa; and
a coating coupled to the glass substrate and overlaying the crack,
wherein the coating has a thickness between 20 nm and 1 μm;
wherein glass of the glass substrate has a crack-onset strain, and wherein stretching of the coating to the crack-onset strain of the glass does not fracture the coating;
wherein flexural strength of the coated glass substrate is a second flexural strength that is greater than the first flexural strength;
wherein the second flexural strength is at least 100 MPa greater than the first flexural strength.
5 . The glass-based assembly of claim 4 , wherein crack-onset stress of the coating is greater than 0.25 GPa and less than 3 GPa.
6 . The glass-based assembly of claim 5 , wherein the crack extends into the surface at least 200 nm and less than 5 μm.
7 . The glass-based assembly of claim 5 , wherein the substrate has a modulus of elasticity greater than 90 GPa.
8 . The glass-based assembly of claim 7 , wherein the coating has a compressive stress of at least 20 MPa at zero strain or flexing of the glass-based assembly.
9 . The glass-based assembly of claim 7 , wherein the glass comprises a refractive index greater than 1.8 at 589 nm.
10 . The glass-based assembly of claim 7 , wherein the glass has a liquidus viscosity less than 1000 Poise and at least 1 centiPoise.
11 . The glass-based assembly of claim 4 , wherein the glass substrate comprises a plurality of flaws, including the crack as one of the plurality, and wherein the plurality of flaws has an average flaw depth in a range of 0.5 to 3 micrometers.
12 . A glass-based assembly, comprising:
a glass substrate comprising a surface, wherein the surface comprises a crack that extends into the surface, wherein the crack has a depth of at least 50 nm but less than 10 μm,
wherein the glass comprises greater than 5 mol % yttria;
wherein the glass substrate if uncoated has a first flexural strength;
a coating coupled to the substrate and overlaying at least a portion of surfaces thereof and the crack, wherein the coating comprises a metal oxide,
wherein glass of the glass substrate has a crack-onset strain, and wherein stretching of the coating to the crack-onset strain of the glass does not fracture the coating;
wherein flexural strength of the coated glass substrate is a second flexural strength that is greater than the first flexural strength,
wherein the first flexural strength is less than 500 MPa, and
wherein the second flexural strength is at least 100 MPa greater than the first flexural strength.
13 . The glass-based assembly of claim 12 , wherein glass of the glass substrate having a refractive index of 1.9 or greater at 589 nm.
14 . The glass-based assembly of claim 12 , wherein the glass substrate if uncoated has a failure strain within a range of 0.3% to 1.5%; and wherein the coating has a crack onset strain within a range of 0.4% to 2.0%.
15 . The glass-based assembly of claim 12 , wherein the glass substrate comprises a modulus of elasticity greater than 90 GPa.
16 . The glass-based assembly of claim 12 , wherein the coating has a thickness between 20 nm and 1 μm.
17 . The glass-based assembly of claim 12 , wherein crack-onset stress of the coating is greater than 0.25 GPa and less than 3 GPa.
18 . The glass-based assembly of claim 16 , wherein the crack extends into the surface at least 200 nm and less than 5 μm.
19 . The glass-based assembly of claim 16 , wherein the glass has a liquidus viscosity less than 1000 Poise and at least 1 centiPoise.
20 . The glass-based assembly of claim 12 , wherein the glass substrate comprises a plurality of flaws, including the crack as one of the plurality, and wherein the plurality of flaws has an average flaw depth in a range of 0.5 to 3 micrometers.