US 9,656,903 B2 · Method of manufacturing high strength glass fibers in a direct melt operation and products formed there from

Abstract

A method of forming high strength glass fibers in a glass melter substantially free of platinum or other noble metal materials, products made there from and batch compositions suited for use in the method are disclosed. One glass composition for use in the present invention includes 50-75 weight % SiO2, 13-30 weight % Al2O3, 5-20 weight % MgO, 0-10 weight % CaO, 0 to 5 weight % R2O where R2O is the sum of Li2O, Na2O and K2O, has a higher fiberizing temperature, e.g. 2400-2900° F. (1316-1593° C.) and/or a liquidus temperature that is below the fiberizing temperature by as little as 45° F. (25° C.). Another glass composition for use in the method of the present invention is up to about 64-75 weight percent SiO2, 16-24 weight percent Al2O3, 8-12 weight percent MgO and 0.25-3 weight percent R2O, where R2O equals the sum of Li2O, Na2O and K2O, has a fiberizing temperature less than about 2650° F. (1454° C.), and a ΔT of at least 80° F. (45° C.). A forehearth for transporting molten glass from the glass melter to a forming position is disclosed. By using furnaces and/or forehearths substantially free of platinum or other noble metal materials, the cost of production of glass fibers is significantly reduced in comparison with the cost of fibers produced using a melting furnace lined with noble metal materials. High strength composite articles including the high strength glass fibers are also disclosed.

Claims20

Dependent claims

A method of forming high strength glass fibers in a continuous system having a glass melting furnace, a forehearth, and a bushing, the method comprising:

supplying a glass batch to the furnace, wherein at least a portion of the furnace is lined with a material substantially free of noble metals thereby forming a furnace glass contact surface,
the glass batch being capable of forming a fiberizable molten glass having a fiberizing temperature from 2,400° F. to 2,900° F. and comprising;
65-75 weight percent SiO2;
15-30 weight percent Al2O3;
5-20 weight percent MgO;
0-4 weight percent CaO;
1.0-3 weight percent Li2O;
and trace impurities;
melting the glass batch in the furnace by providing heat from a furnace heat source and forming a pool of molten glass in contact with the furnace glass contact surface;
transporting the molten glass from the furnace to the bushing via the forehearth, wherein the forehearth is heated from a forehearth heat source, and wherein the forehearth is at least partially lined with a material substantially free of noble metal materials, forming a forehearth glass contact surface;
discharging the molten glass from the forehearth into the bushing at a predetermined viscosity;
and
forming the molten glass into continuous glass fibers, the fibers having a pristine tensile strength greater than 700 kPsi.

10 more elements

Dependencies are inferred from the claim text.

Method of manufacturing high strength glass fibers in a direct melt operation and products formed there from

Life of this patent

Method of manufacturing high strength glass fibers in a direct melt operation and products formed there from

Life of this patent

Abstract

Claims20