Glasses with improved tempering capabilities
The disclosure relates to glass compositions having improved thermal tempering capabilities. The disclosed glass compositions have high coefficients of thermal expansion and Young's moduli, and are capable of achieving high surface compressions. A method of making such glasses is also provided.
1. A glass composition comprising:
60-72 mol % SiO 2 ;
greater than 0 mol % Al 2 O 3 ;
greater than 0 mol % MgO;
greater than 0 mol % CaO;
8-16 mol % Na 2 O+K 2 O;
0-16 mol % Na 2 O;
0-16 mol % K 2 O;
3-8 mol % ZnO; and
free of B 2 O 3 .
2. The glass composition of claim 1 , comprising >0-10 mol % MgO.
3. The glass composition of claim 1 , comprising >0-12 mol % Al 2 O 3 .
4. The glass composition of claim 1 , comprising >0-15 mol % CaO.
5. The glass composition of claim 1 , comprising >0-15 mol % Na 2 O.
6. The glass composition of claim 1 , wherein the glass composition has a low temperature coefficient of thermal expansion (LTCTE) measured at 25° C. and a high temperature coefficient of thermal expansion (HTCTE) measured at 300° C., and wherein the sum of the LTCTE and the HTCTE is 35×10 −7 /° C. or greater.
7. The glass composition of claim 6 , wherein the sum of the LTCTE and the HTCTE is 37×10 −7 /° C. or greater.
8. The glass composition of claim 6 , wherein the sum of the LTCTE and the HTCTE is 40×10 −7 /° C. or greater.
9. The glass composition of claim 1 , wherein the glass composition has a temperability, Ψ, and the temperability, Ψ, is equal to or greater than 0.80.
10. The glass composition claim 9 , wherein the temperability, Ψ, is equal to or greater than 0.85.
11. The glass composition claim 9 , wherein the temperability, Ψ, is equal to or greater than 0.90.
12. A glass composition comprising:
60-72 mol % SiO 2 ;
greater than 0 mol % Al 2 O 3 ;
greater than 0 mol % MgO;
greater than 0 mol % CaO;
6-16 mol % Na 2 O+K 2 O;
0-16 mol % Na 2 O;
0-16 mol % K 2 O;
3-8 mol % ZnO;
a coloring component; and
free of B 2 O 3 .
13. The glass composition of claim 12 , wherein the coloring component comprises Fe 2 O 3 , V 2 O 5 , Cr 2 O 3 , TiO 2 , MnO 2 , NiO, ZnO, CuO, NiO, Co 3 O 4 , or combinations thereof.
14. The glass composition of claim 12 , wherein the total mol % of coloring components is from 0 to 4 mol %.
15. The glass composition of claim 12 , wherein the glass composition exhibits a color presented in SCE color space coordinates with the following values: a*=from about −5 to about −1; b*=from about 5 to about 18; and L*>83.
16. The glass composition of claim 12 , wherein the glass composition when rolled into a 2 mm thick slab has a transmission and wherein the transmission is greater than 80% at 575 nm.
17. The glass composition of claim 12 , comprising 8-16 mol % Na 2 O+K 2 O.