Glass composition for producing high strength and high modulus fibers
View Patent ↗A glass composition including SiO 2 in an amount from about 70.0 to about 78.2% by weight, Al 2 O 3 in an amount from about 18.6 to about 26.2% by weight, MgO in an amount from about 3.1 to about 10.7% by weight, CaO in an amount from 0.0 to about 7.6% by weight, Li 2 O in an amount from about 0.1 to about 5.0% by weight, and Na 2 O in an amount from 0.0 to about 0.2% by weight is provided. In exemplary embodiments, the glass composition is free or substantially free of B 2 O 3 and fluorine. The glass fibers have a specific strength between about 1.6×10 6 J/kg and 2.24×10 6 J/kg and a specific modulus between about 3.3×10 7 J/kg and 3.7×10 7 J/kg. Glass fibers formed from the inventive composition possess exceptionally high specific strength and a low density, which make them particularly suitable in applications that require high strength, high stiffness, and low weight, such as in wind blades and aerospace structures.
1. A composition for preparing high strength, light weight glass fibers, the composition comprising:
SiO 2 in an amount from 71.27 to 78.2% by weight of the total composition,
Al 2 O 3 in an amount from 18.0 to 26.2% by weight of the total composition,
MgO in an amount from 3.1 to 10.7% by weight of the total composition,
CaO in an amount from 0.0 to 2.0% by weight of the total composition,
Li 2 O in an amount from 0.1 to 2.0% by weight of the total composition,
Na 2 O in an amount from 0.0 to 0.2% by weight of the total composition, and
ZrO 2 in an amount from 0.0 to 1.0% by weight of the total composition;
wherein the composition is substantially free of B 2 O 3 .
2. The composition of claim 1 , wherein:
Al 2 O 3 is present in an amount from 18.6 to 26.2% by weight of the total composition.
3. The composition of claim 1 , wherein:
SiO 2 is present in an amount from 71.27 to 73.0% by weight of the total composition,
Al 2 O 3 is present in an amount from 18.6 to 21.0% by weight of the total composition, and
MgO is present in an amount from 8.0 to 10.7% by weight of the total composition.
4. The composition of claim 1 , wherein:
SiO 2 is present in an amount from 71.27 to 72.67% by weight of the total composition,
Al 2 O 3 is present in an amount from 18.6 to 20.67% by weight of the total composition,
MgO is present in an amount from 4.74 to 10.7% by weight of the total composition,
CaO is present in an amount from 0.0 to 1.89% by weight of the total composition,
Li 2 O is present in an amount from 0.1 to 1.43% by weight of the total composition, and
Na 2 O in an amount from 0.0 to 0.05% by weight of the total composition.
5. The composition of claim 1 , wherein:
SiO 2 is present in an amount from 71.27 to 72.49% by weight of the total composition,
Al 2 O 3 is present in an amount from 18.6 to 20.49% by weight of the total composition,
MgO is present in an amount from 4.99 to 10.7% by weight of the total composition,
CaO is present in an amount from 0.0 to 1.89% by weight of the total composition,
Li 2 O is present in an amount from 0.1 to 0.2% by weight of the total composition, and
Na 2 O in an amount from 0.0 to 0.05% by weight of the total composition.
6. The composition of claim 1 , wherein:
SiO 2 is present in an amount from 71.27 to 72.67% by weight of the total composition,
Al 2 O 3 is present in an amount from 18.6 to 20.67% by weight of the total composition,
MgO is present in an amount from 3.77 to 10.7% by weight of the total composition,
CaO is present in an amount from 0.0 to 2.07% by weight of the total composition,
Li 2 O is present in an amount from 0.1 to 2.0% by weight of the total composition, and
Na 2 O in an amount from 0.0 to 0.05% by weight of the total composition.
7. The composition of claim 6 , wherein:
MgO is present in an amount from 4.74 to 10.7% by weight of the total composition.
8. The composition of claim 1 , wherein the composition is substantially free of fluorine.
9. The composition of claim 1 , wherein the composition has a ΔT no greater than 87°C.
10. The composition of claim 1 , wherein the composition has a log 3 temperature from 1,340° C. to 1,650° C.
11. The composition of claim 1 , wherein the composition has a liquidus temperature no greater than 1,700° C.
12. The composition of claim 1 , wherein the composition is prepared in a refractory tank melter.
13. The composition of claim 1 , wherein SiO 2 is present in an amount from 71.27 to 73.0% by weight of the total composition.
14. The composition of claim 1 , wherein Al 2 O 3 is present in an amount from 18.6 to 21.0% by weight of the total composition.
15. The composition of claim 1 , wherein MgO is present in an amount from 8.0 to 10.7% by weight of the total composition.