CA1045641A - Glass fiber compositions - Google Patents

Glass fiber compositions

Info

Publication number
CA1045641A
CA1045641A CA225,387A CA225387A CA1045641A CA 1045641 A CA1045641 A CA 1045641A CA 225387 A CA225387 A CA 225387A CA 1045641 A CA1045641 A CA 1045641A
Authority
CA
Canada
Prior art keywords
percent
weight
glass
glass fiber
sio2
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA225,387A
Other languages
French (fr)
Other versions
CA225387S (en
Inventor
Edward M. Hunia
Jerome A. Burgman
Homer E. Neely (Jr.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
PPG Industries Inc
Original Assignee
PPG Industries Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by PPG Industries Inc filed Critical PPG Industries Inc
Priority to CA225,387A priority Critical patent/CA1045641A/en
Application granted granted Critical
Publication of CA1045641A publication Critical patent/CA1045641A/en
Expired legal-status Critical Current

Links

Landscapes

  • Glass Compositions (AREA)

Abstract

ABSTRACT OF THE DISCLOSURE
Glass fibers having high tensile strength in excess of 570,000 pounds per square inch containing carefully selected quantities of SiO2, A12O3, MgO, CaO, TiO2, B2O3, Na2O, BaO and Li2O are disclosed.
The glass fibres contain 53 to 57.3 percent by weight as SiO2, 16.3 to 18.5 percent by weight as Al2O3, 6.6 to 10.5 percent by weight as MgO, 8.5 to 12.7 percent by weight as CaO,0.6 to 0.8 percent by weight as TiO2, 2.0 to 4.1 percent by weight as B2O3 , 0.8 to 3.3.percent by weight as Na2O, 0.0 to 4.1 percent by weight as BaO and 0.0 to 1.0 percent by weight as Li2O. The glasses from which the fibres are made have softening points below 1,650°F and liquidus temperatures below 2210°F.

Description

iO4~1 ~ Background of the Invention .
- The present invention relates to glass fiber compositions having lncreased tensile strengths over conventional "E" glass fibers.
Glasses in order to be suited for glass fiber manufacture must satisfy several criteria.
Since fine glass fibers present a large surface area to volume ratio, compositions resistant to water and chemical attack are necessary.
High alkali content is undesirable since water adsorbed from the atmosphere can tissolve the alkall, initiating reaction with the silicate in the glass and ultimately deseroying the glass. Therefore, the alkali metal content of glass fiber compositions must be limited.
In the formation of flne glass fibers, it iB desirable to have a glass compos~tion which may be melted and refined at high rates at relatively low temperatures. The glass should have a workable viscosity over a wide range of relatively low temperatures. The glass should have a low liquldus temperature and a llmlted devltrlflcation rate. It 19 desirable for the color of the glass, as melted, to be such that heat 19 readily transmitted through the glass.
0f particular importance is the use of glass fibers for rein-forcing resinous articles known as laminates. Laminates are formed by impregnating glass fiber cloth, glass fiber chopped strand, or glass fiber mat with a resinous composition. The function of the glass fibers is to reinforce the article and provide a strength far superior to the hardened resin composition alone. In addition, glass fibers have found great utility in the reinforcement of rubber articles such as tires, power transmission belts, and the like. The glass fibers are normally incorporated into these rubber-reinforced articles in cord form to provide additional strength to these elastomeric type articles. There-fore, it is apparent that glass fibers having high tensile strength to impart strength to rubber-reinforced articles are desired.
The most common glass fiber composition used for reinforcement of articles is the "E" glass composition which typically consists of 54.4 percent SiO2, 13.~4 percent A12O3, 21.7 percent CaO, 0.4 percent NgO, 8.5 percent B2O3, 0.5 percent F2, 0.7 percent Na2O, 0.5 percent TiO2, and 0.2 percent Fe2O3.
This "E" glass composition demonstrates tensile strengths of 400,000 to 500,000 pounds per square inch for fibers measuring from 12.5 x 10-5 inches to 70 x 10-5 inches in diameter.
Other compositions than "E" glass exhibiting high tensile strengths in fibrous form are also known. These glass compositions typi-cally have an extremely high percentage of SiO2, usually greater than 65 percent, and, in addition, have an increased amount of A12O3, typically greater than 25 percent. These glass compositions produce fibers which demonstrate tensile strengths on the order of 600,000 pounds per square inch ~045641 for fibers measuring from 35 x 10-5 inches to 64 x 10-5 inches in di-ameter. Tensile strengths arrived at by these glass compositions are very advantageous for reinforcing purposes. ~owever, due to the high amount of SiO2 and A1203 present in these glasses, the liquidus tempera-tures of these compositions are normally greater than 2600F., which substantially reduces the life of refractories and metals used in the melting and forming operations producing these fibers. An example of a high tensile strength glass is disclosed in U.S. Patent 3,402,055.
This glass consists of 65 percent SiO2, 25 percent A12O3 and 10 percent MgO and exhibits tensile strengths of about 637,000 pounds per square inch.
This magnesia-silica-alumina glass will hereinafter be referred to as "S"
glass. The liquidus temperature for this glass is between 2630 and 2650F.
Glasses with liquidus temperatures such as these require increased melting and processing temperatures over "E" glass, thus having adverse effects - on refractory lining in melting tanks and on bushing life.
- Therefore, it is still a desire in the art to produce glass fibers useful for reinforcement of articles which have tensile strength greater than "E" glass from a glass composition which has a relatively low liquidus temperature, maximum chemical inertness, maximum heat trans-fer through the glass, and a limited devitrification rate.

Summary of the Invention - In accordance with the practice of the instant invention, the aforementioned properties and other properties can be achieved by preparing a glass fiber composition which contains 53 to 57.3 percent by weight as - SiO2, 16.3 to 18.5 percent by weight as A1203, 6.6 to 10.5 percent by weight as MgO, 8.5 to 12.7 percent by weight as CaO, 0.6 to 0.8 percent by weight as TiO2, 2.0 to 4.1 percent by weight as B203, 0.8 to 3.3 percent by welght as Na20, 0.0 to 4.1 yercent by welght as BaO and 0.0 to 1.0 percent by welght as L120.
The comblnation of the components at the levels deslgnated lmpart the necessary properties to the glass fibers formed therefrom.
Other components such as Fe203 may be present due to impurltles in the starting glass batch materials. However, Fe203 should be llmited to about 0.3 percent maximum, otherwise the glass melt com-position may have inadequate heat penetration during processing.
Li~uidus temperatures of below 2210F are encountered with the aforementloned range of glass composltlon. Thls liquidus temperature is surprisingly low in comparison with the tensile strength achleved by the range of components necessary ln the practice of the instant in-vention. Thus,the life of the refractories, used in the melting and re-fining process, which contact the glass is greatly increased while an increase ~n tensile strength of the glass fibers produced over conventional "E" glass is realized.
Glasses of the aforementioned range of compositions have softening points below 1,650F and glass fibres made therefrom have tensile strengths greater than 570,000 pounds per square inch.
The invention will be more clearly illustrated by the examples below. However, these examples which describe specific embodiments should not be construed to limit the invention in any way.
EXAMPLE I
The following raw batch materials were weighed out in the amounts indicated to formulate the preferred composition A.

~q - Table 1 Raw Batch Materials Weight in Grams Silica 169.0 Clay 198.2 Dolomite 160.0 Magnesium Oxide 6.9 Boric Acid 34.5 Soda Ash 6.4 -Barlum Carbonate 25.0 The raw batch materials were placed in a Twin Shell Blender and thoroughly mixed by rotating the blender for 30 minutes. After - mixing, the batch was transferred to a 4-inch diameter silica crucible and inserted in a refractory furnace. The batch was heated to a temper-ature of about 2700F. for a period of 6 hours. After this heating, the molten glass was removed from the furnace and poured onto a steel plate to produce a glass patty approximately 1/2 inch thick by about 4 inches by 4 inches square. The glass patty was placed in a furnace, preheated to about 1100F. The power to the furnace was turned off and the furnace was allowed to cool slowly to room temperature over a period of about - 18 hours to anneal the glass. The annealed glass patty was then removed from the annealing furnace and broken into small chunks.
- The chunks of glass were then placed in a single orifice -80 percent platinum, 20 percent rhodium bushing, and remelted and refined by heatlng the bushing to about 2800F. and holding at this temperature for 1 hour. The bushing temperature was then lowered to the fiberizing temperature, 2450F., and a single filament was drawn from the bushing approximately 40 x 10-5 inches in diameter at a rate of about 1600 feet per minute.

The single orifice bushlng used in fabricating the fiber was 3 inches ~long by 1-5/8 inches square. The bushing single orifice was .047 inch in inside diameter, .080 inch long, and had an exit outside diameter of under .060 inches.
Immediately after the glass fiber made from the above composition was drawn, several l-inch samples were obtained. The samples were then tension loaded in a monofilament tensile testing machine to determine their tensile breaking load. The tensile strength in pounds per square inch was then`calculated by dividing the breaking load in pounds by the cross-sectional area of the fiber in square inches.
- Two batches of glass with a composition as above were made. The softening points of these compositions were 1620F and 1628F and had liquidus temperatures of about 2175F. The tensile strength of monofilament fibers on testing displayed strengths of between 590,000 to 650,000 pounds per square inch.
The average composition of the glass fibres was 56.6 percent by weight as Si02, 18.5 percent by weight as A1203, 0.3 percent by weight as Fe203, 9.3 percent by weight as MgO, 10.7 percent by weight as CaO, 0.6 percent by weight as Ti02, 2.0 percent by weight as B203, 1.0 percent by weight as Na20 and 1.0 percent by weight as Li2O.
EXAMPLE II
The following raw batch materials were weighed out in the amounts indicated to formulate the preferred composition B:
- TABLE II
Raw Batch Materials Weight in Grams Silica 181.5 Clay 203.3 Dolomlte 137.6 Magnesium Oxide 2.0 Boric Acid 28.1 Soda Ash 27.2 Barium Carbonate 20.3 This batch was melted, refined, annealed, and fibers were drawn therefrom in accordance with the procedl~re of Example I. This glass batch had a softening point of 1605~F to 1619F and a liquidus temperature of between 2060F and 2108F. Testing of monofilament fibers formed as above described had tensile strengths between 585,000 pounds per square inch and 630,000 pounds per square inch.
The composition of the glass fibres was 57.3 percent by weight as SiO2, 16.5 percent by weight as A1203, 0.2 percent by weight as Fe203, 6.6 percent by welght as MgO, 8.8 percent by weight as CaO, 0.7 percent by weight as TiO2, 3.3 percent by weight as B203 and 3.3 percent by weight as BaO.
EXANPLE III
The following raw batch materials were weighed out in the amounts indicated to formulate the composition C:

Raw Batch MaterialsWeight in Grams Silica 169.3 Clay 189.2 Dolomite - 192.8 Magnesium Oxide 7.7 Boric Acid 26.2 Soda Ash 8~5 Barium Carbonate 6.3 The above batch materials were melted, refined, annealed, and fibers were drawn therefrom in accordance with the method of Example I. The glass - formed from this batch had a softening point of 1623F to 1625F and the liquidus temperature of between 2200F and 2208F. Tensile strengths of the glass fibers drawn from these compositions were between 585,000 pounds per square inch and 650,000 pounds per square inch.
The composition of the glass fibres was 54.7 percent by weight as SiO2, 15.8 percent by weight as A1203, 0.2 percent by weight as Fe203, 10.5 percent by weight as MgO, 12.7 percent by weight as CaO,0.7 percent by weight as TiO2, 3.2 percent by weight as B203, 1.1 percent by weight as Na20 and 1.1 percent by welght as BaO.

EXAMPLE IV
The following raw batch materials were weighed out in the amounts indicated to formulate the preferred composltlon D:

.r Raw Batch Materials Weight in Grams Sillca 147.8 Clay 184.4 Dolomite 169.1 Boric Acid 16.7 Magnesium Oxide 8.3 10 Soda Ash 8.1 Spodumene 65.5 The above ingredients were mlxed, melted, annealed, and flbers were drawn therefrom according to the procedure in Example I. Glass made from this batch had a liquidus temperature of 2170F to 2190F and a soft-ening point of 1560F to 1580F. Tensile strength of fibers drawn from thls glass composition were between 595,000 pounds per square lnch to 635.000 pounds per square lnch.
The composition of the glass flbers was 54.8 percent by weight as SiO2, 16.3 percent by weight as A1203, 0.2 percent by weight as Fe203, 8.7 percent by weight as MgO, 10.3 percent by welght as CaO, 0.7 percent by weight as TiO2, 4.1 percent by weight as B203, 0.8 percent by.weight as Na20 and 4.1 percent by weight as BaO.
EXAMPLE V
The following raw batch materials were weighed out in the amounts indicated to formulate the preferred composition E:

.

~q Raw Batch Material Weight in Grams Silica 147.6 Clay 223.9 Dolomite 130.6 Boric Acid 30.1 Magnesium Oxide 18.9 Soda Ash 11.3 Barium Carbonate 24.2 The above materials were mixed, melted, annealed, refined, and fibers were drawn therefrom in accordance with the procedure of Example I.
This glass had a softening point of 1633f and a liquidus temperature of 2200F. Fibers drawn from this glass had a tensile strength of between 585,000 pounds per square inch and 620,000 pounds per square inch.
The composition of the glass fibres was 53.0 percent by weight as SiO2, 18.5 percent by weight as A1203, 0.2 percent by weight as Fe203, lO.O percent by weight as MgO, 8.5 percent by weight as CaO, 0.8 percent by weight as TiO2, 3.6 percent by weight as B203, 1.4 percent by weight as Na20 and 4.0 percent by weight as BaO.
The liquidus temperature determinations for the above specific compositions were made by the conventional 24 hour liquidus technique in which ground glass is placed in a shell or platinum boat, the shell or boat is then placed in a gradient furnace with one end about 1300F and the other about 2500F, heated and maintained in equilibrium with the furnace for 24 hours and then removed for microscopic determination of the crystal-glass interface of the sample. Correspondence of the crystal-glass interface with the known lateral position to temperature relation for the furnace establishes the liquids.
Softening point determination is by the conventional ASTM-C
338-57 method. The glass fiber is prepared and placed in a uniform _ g _ 1C~45641 1 temperature furnace. Temperature is lncreased and temperature rise and
2 fiber elongation are recorded. ~hen the elongatlon rate meets the pre-4 set standard of the test, the temperature is noted as the softenlng point.

_ 9. _ ~, 1~45641 The foregoing Table represents the properties of the herein-before set forth Examples and compares the glasses therewith.

Table 6 Composition Softening Point F. Liquidus F. Tensile Strength PSI x 103 "E" Glass 1540-1560 2170-2~90 400-500 "S" Glass 2630-2650 637 The improved tensile strengths of the glass fiber compositions herein disclosed permit the production of improved glass reinforced plastic articles and improved glass reinforced rubber articles such as tires and power transmission belts.
It is anticipated that these fiber glass compositions will find particular acceptance in the production of various types of aircraft equip-ment where high strength to weight ratios are important. Glasses with - these improved properties are readily melted and formed in the conventional commercial glass fiber strand-producing facilities. Combination of the various ingredients permits melting and forming at comparable temperatures with "E" glass while providing improved tensile strengths.
While the present invention has been described in terms of spe-cific examples, the scope of the invention should not be limited except as is ~et forth in the appended claims.

Claims

CLAIMS:

--1. A glass fiber composition consisting essentially of 53 percent to 57.3 percent by weight as SiO2, 16.3 percent to 18.5 per-cent by weight as Al2O3, 6.6 percent to 10.5 percent by weight as MgO, 8.5 percent to 12.7 percent by weight as CaO, 0.6 percent to 0.8 percent by weight as TiO2, 2.0 percent to 4.1 percent by weight as B2O3, and 0.8 percent to 3.3 percent.by weight as Na2O having a tensile strength of greater than 570,000 pounds per square inch formed from a glass composition having a softening point below 1650°F. and a liquidus temperature below 2210°F.

--2. The glass fiber of Claim 1 having therein 0.1 percent to 4.1 percent by weight as BaO.

--3. The glass fiber of Claim 2 having therein 0.01 percent to 1.0 percent by weight as Li2O.

--4. The glass fiber of Claim 1 having therein 0.01 percent to 1 percent by weight as Li2O.

--5. A glass fiber reinforced plastic article which contains glass fibers of Claim 1.

--6. A glass fiber reinforced elastomeric article which con-tains the glass fibers of Claim 1.

--7. A glass fiber composition consisting essentially of 56.6 percent by weight as SiO2, 18.5 percent by weight as Al2O3, 0.3 percent by weight as Fe2O3, 9.3 percent by weight as MgO, 10.7 percent by weight as CaO, 0.6 percent by weight as TiO2, 2.0 percent by weight as B2O3, 1.0 percent by weight as Na2O, and 1.0 percent by weight as Li2O having a tensile strength of greater than 570,000 pounds per square inch, formed from a glass composition having a softening point below 1650°F. and a liquidus temperature below 2210°F.

--8. A glass fiber composition consisting essentially of 57.3 percent by weight as SiO2, 16.5 percent by weight as Al2O3, 0.2 percent by weight as Fe2O3, 6.6 percent by weight as MgO, 8.8 per-cent by weight as CaO, 0.7 percent by weight as TiO2, 3.3 percent by weight as B2O3, and 3.3 percent by weight as BaO having a tensile strength of greater than 570,000 pounds per square inch formed from a glass composition having a softening point below 1650°F. and a liquidus temperature below 2210°F.

--9. A glass fiber composition consisting essentially of 54.7 percent by weight as SiO2, 15.8 percent by weight as Al2O3, 0.2 percent by weight as Fe2O3, 10.5 percent by weight as MgO, 12.7 percent by weight as CaO, 0.7 percent by weight as TiO2, 3.2 percent by weight as B2O3, 1.1 percent by weight as Na2O, and 1.1 percent by weight as BaO having a tensile strength greater than 570,000 pounds per square inch formed from a glass composition having a softening point below 1650°F. and a liquidus temperature below 2210°F.

--10. A glass fiber composition consisting essentially of 54.8 percent by weight as SiO2, 16.3 percent by weight as Al2O3, 0.2 percent by weight as Fe2O3, 8.7 percent by weight as MgO, 10.3 percent by weight as CaO, 0.7 percent by weight as TiO2, 4.1 percent by weight as B2O3, 0.8 percent by weight as Na2O, and 4.1 percent by weight as BaO having a tensile strength greater than 570,000 pounds per square inch formed from a glass composition having a softening point below 1650°F. and a liquidus temperature below 2210°F.

--11. A glass fiber composition consisting essentially of 53.0 percent by weight as SiO2, 18.5 percent by weight as Al2O3, 0.2 percent by weight as Fe2O3, 10.0 percent by weight as MgO, 8.5 percent by weight as CaO, 0.8 percent by weight as TiO2, 3.6 percent by weight as B2O3, 1.4 percent by weight as Na2O, and 4.0 percent by weight as BaO having a tensile strength of greater than 570,000 pounds per square inch formed from a glass composition having a softening point below 1650°F. and a liquidus temperature below 2210°F.--
CA225,387A 1975-04-24 1975-04-24 Glass fiber compositions Expired CA1045641A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA225,387A CA1045641A (en) 1975-04-24 1975-04-24 Glass fiber compositions

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA225,387A CA1045641A (en) 1975-04-24 1975-04-24 Glass fiber compositions

Publications (1)

Publication Number Publication Date
CA1045641A true CA1045641A (en) 1979-01-02

Family

ID=4102898

Family Applications (1)

Application Number Title Priority Date Filing Date
CA225,387A Expired CA1045641A (en) 1975-04-24 1975-04-24 Glass fiber compositions

Country Status (1)

Country Link
CA (1) CA1045641A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2354105A1 (en) 2010-02-05 2011-08-10 3B Glass fibre composition and composite material reinforced therewith
EP2354104A1 (en) 2010-02-05 2011-08-10 3B Glass fibre composition and composite material reinforced therewith
EP2354106A1 (en) 2010-02-05 2011-08-10 3B Glass fibre composition and composite material reinforced therewith
WO2013156477A1 (en) 2012-04-18 2013-10-24 3B Fibreglass Sprl Glass fibre composition and composite material reinforced therewith

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2354105A1 (en) 2010-02-05 2011-08-10 3B Glass fibre composition and composite material reinforced therewith
EP2354104A1 (en) 2010-02-05 2011-08-10 3B Glass fibre composition and composite material reinforced therewith
EP2354106A1 (en) 2010-02-05 2011-08-10 3B Glass fibre composition and composite material reinforced therewith
WO2011095597A1 (en) 2010-02-05 2011-08-11 3B Fibreglass Sprl Glass fibre composition and composite material reinforced therewith
WO2011095601A1 (en) 2010-02-05 2011-08-11 3B Fibreglass Sprl Glass fibre composition and composite material reinforced therewith
WO2011095598A1 (en) 2010-02-05 2011-08-11 3B Fibreglass Sprl Glass fibre composition and composite material reinforced therewith
US9102564B2 (en) 2010-02-05 2015-08-11 3B Fibreglass Sprl Glass fibre composition and composite material reinforced therewith
WO2013156477A1 (en) 2012-04-18 2013-10-24 3B Fibreglass Sprl Glass fibre composition and composite material reinforced therewith

Similar Documents

Publication Publication Date Title
US3892581A (en) Glass fiber compositions
KR900003447B1 (en) Tempered Glass Product and Manufacturing Method
KR100391963B1 (en) Glass fiber without boron
US4824806A (en) Glass fibers having low dielectric constant
US4665039A (en) Porous glass, process for its production and glass material used for the production
US4363878A (en) Alkali- and heat-resistant inorganic fiber
CA1265165A (en) Alkali-resistant glass fiber
US4764487A (en) High iron glass composition
US5064785A (en) Alkali-resistant glass for forming glass fibers
EP1886978A1 (en) Method for making glass fibers
US4102692A (en) Reinforcing glass fibers of MgO-CaO-ZnO-Al2 O3 -SiO2 -TiO2
KR100822243B1 (en) High Temperature Resistant Glass Inorganic Fiber
JP5356683B2 (en) Glass strand capable of strengthening organic and / or inorganic materials
CA2769401A1 (en) Improved modulus, lithium free glass
US3840379A (en) Glass compositions
CN120309168B (en) High-strength, heat-resistant glass and preparation method thereof
CN114988699B (en) Low dielectric glass composition, low dielectric glass fiber and product
US7811954B2 (en) Glass yarn for reinforcing organic and/or inorganic materials
GB2220654A (en) Glass composition and batch blend for its production
US3484259A (en) High strength-high modulus glass fibers
US4014705A (en) Glass compositions
US3408213A (en) Glass fiber compositions
US4835122A (en) Glass fibers resistant to basic media and their application to reinforcing of cement
US3360386A (en) Glass fiber composition
US3901719A (en) Glasses and glass-ceramics containing rutile fibers