JPH05504928A - Reinforced glass and/or ceramic matrix composites and methods of manufacturing such composites - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Reinforced glass and/or ceramic matrix composites and such composites body manufacturing method The present invention relates to fiber reinforced glass and ceramic matrix composites and such The present invention relates to a method for producing a composite.

Generally, the production of glass matrix composites involves adding glass to a mat of reinforcing fibrous material. Achieved by impregnating a slurry of powder or particles.

The reinforcing fiber impregnated mat is then dried and stored as prepreg or directly affected. They are then cut into the desired shape and placed under heat and pressure. molded into a glass matrix and fused together. A typical manufacturing method is U.S. Patent No. 4, No. 511,663 and No. 4,485,179.

U.S. Pat. No. 3,646,908 (issued March 7, 1972) describes continuous length The lath fibers are first pulled up and down with a spread roller to create a tape, and then this into a bath containing glass powder slurry. Remove excess slurry from the wet tape; This is then rolled onto a flat sight drum to hold the roll together.

Remove the crumbs and hot press. A variation of this method is described in U.S. Pat. No. 3,681. It can be found in No. 187.

U.S. Pat. No. 4,263,367 discloses a prefabricated isotropically spread or planar By using a graphite paper cloak with randomly arranged fibers inside the Attempts to improve the reinforcement of lath matrix composites have been described. Solvent immersion or After removing the binder material from the mat by burning, the mat is Soak in lari. These mats are then stacked with alternating layers of powdered glass I really bless you. Randomly arranged reinforcing fibers are glass matrix composite Gives the body reinforced mechanical strength.

A further attempt to produce a glass matrix containing reinforcing fibers was Le, Bowen and Phillips “Carbon Fiber Compos it'', Journal of Material 5science, 7(19 72), described in the paper on page 663. These methods use chopped carbon fiber. Dispersing fibers and powdered matrix material in isopropyl alcohol includes.

Alcohol is removed by infrared radiant heat until the mixture has a hard consistency. Then, stir the mixture continuously. This mixture is then placed into the die assembly. Hot press.

Although the above methods are satisfactory, they are quite labor intensive. It is something that A simpler, more efficient method with better compositional control is desirable.

The invention particularly relates to the following steps: a, (1) reinforcing fibers, (2) glass fibers, and (3) at least one binder; producing a dilute aqueous slurry having a solid component, including: b. Destabilize the aqueous slurry: c4 Collect this solid component on a porous support; d. Dehydrate and dehydrate this collected solid. After drying, the reinforcing fibers and glass fibers are tangled and randomly arranged on the surface of the mat. producing a dry composite mat of: and e. stacking a plurality of these mats or their fragments; The glass fibers are melted into a continuous glass matrix and the binder material is added between them. heat press under conditions sufficient to substantially remove reinforcing fibers and preserve the integrity of the reinforcing fibers. do.

Manufacture of fiber-reinforced glass matrix composite article characterized by including various steps It's in the method.

The method of the invention reduces the amount of matrix material due to negligible loss of matrix material during processing. provides better and more precise control than the volume fraction of reinforcing material relative to the box material.

In a related aspect, the invention also provides heat-pressed composite articles in the absence of pressure. , higher than the temperature at which the glass matrix softens but the reinforcing fibers deteriorate. By heating to a lower temperature and lofting the composite article to reduce its thickness. By holding the composite article within this temperature range for a sufficient period of time to increase A method of manufacturing a lofted fiber reinforced glass matrix composite article.

The present invention also relates to graphite fibers, metal coated graphite fibers, silica fibers, stone English fiber, ceramic fiber, metal or alloy fiber, silica carbide fiber, or Contains reinforcing fibers with a length of 3 mm to 25 mm selected from a mixture thereof, and Contains 3-35% solids by volume during coalescence, with substantially uniform reinforcing fibers throughout the composite. distributed and randomly arranged in a glass matrix composite.

The method of the invention includes multiple steps. The first step is to prepare a dilute aqueous slurry of solid components. or the manufacture of suspensions. Solid components include glass fibers, reinforcing fibers, and less Both contain one type of binder material. The binder material may also be fibrous . The slurry is then destabilized, wet-laid onto a porous support, and spun onto the support. The solid components of lari are collected to produce a composite mat. Collecting solid components is done using a vacuum. Facilitated by use. The composite mat is then dehydrated and dried to form a dry mat is generated. In the drying mat, glass fibers, reinforcing fibers, and if present are tangled and randomly arranged on the surface of the fibrous binder material or mat.

The single mat or pieces thereof are then heat pressed to form a fiber-reinforced glass matrix composite. Although a composite article can be produced, the advantageous results in terms of thickness and strength are gills when stacking more than one mat or pieces together and then heat pressing. It will be done.

The method of the invention offers numerous advantages. First, it consists of the various components that make up the solid component. Promote the formulation of Secondly it dries the mat and produces a glass matrix composite object Provides random alignment of reinforcing fibers on both sides of the product. Random composition is quasi-isotropic provides mechanical strength with little regard to the plane of the sheet or the orientation of the coordinating plane.

Third, it provides reinforcing fibers to the glass matrix in the manufactured article produced. Reinforcement for glass fibers in the solid component of dilute slurries with a reproducible volume fraction of allows the production of a consistent product approximately equal to the volume fraction of the fiber used.

The present invention utilizes glass fibers and reinforcing fibers that form the matrix after thermal coalescence of the mat. , and at least one binder material, in an aqueous medium. The advantageous result is that at least a portion of the binder material or fibers, such as polyolefin obtained when it is in the form of fibers. Most, if not all, solid state The use of binder fibers about minutes helps mat formation and collection and solids loss and maximize reproducibility of results. Glass fibers, reinforcing fibers and binders The order of addition of the dermal materials is not critical. However, the desired result is that reinforcing fibers and binders obtained when glass fibers are added to an aqueous medium after the material has been well dispersed. .

Glass fibers suitable for the purposes of the present invention are dispersible in aqueous media and heat and pressure resistant. It is made of fiberglass that deforms and melts into a monolithic structure. soda ash glass, hou ・Silicate glass, quartz and lithium-aluminum silicate glass are suitable Forms glass fibers. Glass fibers usually constitute 45-97% by volume of the fixed component. to be accomplished. When the amount of glass fiber exceeds approximately 97% by volume, the glass matrix composite It is not possible to achieve sufficient reinforcement of body articles. The amount of glass fiber is approximately 45% by volume. between the reinforcing fibers after heat pressing the mat into the manufactured article. To fill the space of ``matrix shortage J'' or insufficient amount of matrix There are only 100% carbonaceous material.

Reinforcing fibers include graphite fiber, metal-coated graphite fiber, silica fiber, and quartz. Fibers, ceramic fibers, metal or metal alloy fibers, Noricon carbide], fibers, or a mixture thereof. Metal fiber and metal coated grapher The fiber metal is used under hot press conditions for the structural material of molds used in hot presses. It should be substantially inert. The reinforcing fibers are advantageously stainless steel fibers or is a nickel-coated graphite fiber.

The metallization need not be nickel. U.S. Patent No. 14.511.663 includes the book The following metals, namely Y, Zr, which can be advantageously used as the metal coating of the reinforcing fiber of the invention , Nb, Mo, Ag, Cd, Ta, W, Zn, Cu, Co.

Description of use of Fe, Mn, Ga, V, Ti, Sc, AI, Mg, Au and Pt has been done. The magnetic or electrical properties of metals can be added to the produced article if enough metal is present. Moving. Noricon, as described in U.S. Patent No. 4,485,179 Carbide fibers can also be used.

The amount of reinforcing fibers is preferably from 3 to 35% by volume of the solids component. Reinforcement less than about 3% The amount of fiber used will provide inadequate reinforcement. The amount exceeding about 35% is the same temperature of the matrix. It is produced by bringing about.

The reinforcing fibers are present in the glass matrix composite article produced by the method of the present invention. distributed substantially uniformly throughout and randomly over the surface formed by the article. Coordinated. That is, there is virtually no preferred orientation of the fibers in the x, y directions. . The uniform distribution and random arrangement of reinforcing fibers also improves the glass matrix complex. It is also present in the dry mat that is the raw material for the production of coalescent products. The reinforcing fibers used are At least 0.125 inches (3mm), preferably 0.18 inches (4mm) ~1.00 (25 mm), most preferably about 0.75 inch (19 mm) average have length.

The binder material destabilizes the solids by effectively aiding in the collection of solid components from the dilute slurry. It is a material that hardens, forms into a mat, and becomes sticky. Generally, the binder is a fiber, It can be in the physical form of powder, particles or an aqueous dispersion thereof.

Typical binder materials include starch, latex dispersions, synthetic polymers and and natural polymers. The binder material is advantageously a synthetic or natural polyester. It's Ma.

The amount of solid components 1-b of the binder material is generally preferably 5-15%.

Amounts of binder less than about 1% may reduce the production of a cohesive composite mat or It is extremely difficult. On the other hand, if more than about 20% binder is used, the heat press time will be Increases uneconomically due to burning or vaporizing the binder. Also economically rational It is difficult, if not impossible, to eliminate the generated porosity within a reasonable period of time. .

an anionic or cationic bond charge sufficient to provide stabilization of the colloid A latex binder with a . if necessary , destabilization of colloids using a polymeric flocculant that is opposite in charge to the charged binder. can help you become more oriented.

Binder material is preferably ethylene/acrylic acid copolymer, polyolefin fibers, or a mixture of the copolymer and polyolefin fibers. fibrous bi Examples of underlayer materials include polyethylene, polypropylene, polyvinyl chloride, Polyester, polystyrene, and acrylonitrile/butadiene/styrene Examples include copolymers.

Binder materials are preferably ethylene/acrylic acid copolymers and polyolefins. It is a combination with fiber. This combination is an ethylene/acrylic acid copolymer or agglomerated It is advantageous because it increases the wet strength of collected solid components or "wet matsutono". It is. Polyolefin fibers are dried composite matt and add stiffness, possibly melted and its subsequent solidification aids in its pre-densification.

In addition to the above three ingredients, other additive materials may be added to the aqueous slurry, such as glass, matte, etc. interfere with the manufacture of or materially degrade the properties of the lix composite manufactured articles. Can be mixed unless otherwise specified. For example, other fibrous materials and granular fillers A fibrid complex can be produced by adding a stimulatory agent. Also, colorants, processing aids Agents such as thickeners, flocculants, and pH adjusting agents may also be included.

The filler material is an essential component of the glass-matrix composite manufactured articles made in accordance with the present invention. It is not a natural ingredient. If used, the filler material is in powder or preferably fibrous form. It can be a body. Although granular fillers are mostly satisfactory, their Some loss is expected. Carbon bran as a suitable granular filler powders, metal-like powders, and other materials that are inert or non-reactive under the processing conditions of the present invention. Examples include materials that are reactive. Combinations of fibrous and granular fillers are also available. Can you use it? Exemplary fill material levels are based on total volume of solid material It falls within the range of 0-15% by volume, preferably 05-10% by volume.

If desired, add a sufficient amount of thickener to the water to improve dispersion of the solid ingredients. I can do it. In addition, some part of the solid component is added in a pre-dispersed form, and most of the solid component is It can also help form a uniform dispersion. Dry the mat partially before heat pressing It can also be made denser.

Dry composite mats can be fully densified, partially densified, or completely densified. Even if it is not highly densified, it can be stored as prepreg or used directly. You can use it. In either case, composite mats are ultimately heat pressed. As a result, the solid components of the composite mat become completely densified, and the glass fibers melt and become continuous. Become a matrix. However, during this period, the reinforcing fibers were distributed almost uniformly and randomly. Coordination is preserved. The heat press also fills the glass matrix with reinforcing fibers. agent (if present), and other additives. heat press The binder material that volatilized therein is not present in the final manufactured article. heat pressed The composite is then cooled and removed from the pressurizing device used.

Heat-pressed composite articles are produced by placing the article or pieces thereof in an air oven. is heated to a temperature higher than the softening point of the matrix material, for example 840°C, and this temperature is Further denaturation can be achieved as desired by holding the temperature for more than one hour.

Then turn off the oven and allow to cool. The cooled article is It is "lofted" in that it has a greater thickness and lower density. at least It is easy to increase the thickness by 5%, for example 5-100%, preferably 10-50%. available. The increase in thickness is the difference in thickness from the original thickness to the thickness before heating and lofting) It is calculated by dividing by. Lofting increases both the bending and insulation properties of manufactured articles. Make it bigger.

The collected and dried mats are placed in a sheet mold Four drier or cylinder. It can be manufactured on conventional papermaking equipment such as a paper machine.

The method of the invention is further illustrated by the following examples. In these examples All parts and percentages are by volume unless otherwise specified. heat pump The volume % of the composite mat that has been compressed is the matrix that is most likely to occur during the heat pressing process. Based on the assumption that material loss is zero for all practical purposes. There is. The binder material will, of course, volatilize during processing. Examples of the present invention are as follows. Comparative examples are shown in capital letters.

Example 1 281 water was thickened with Ig xantham gum. Approximately 19g of styrene/butaje A latex (50% solids by weight) binder was added to the thickened water without stirring. I got it. Next, 233 g of glass fiber (13 microns in diameter, approximately 1.25 cm in length) and 60.6 g of nickel-coated graphite fiber (7 micron diameter, approximately 6.6 g long). 35 mm) was added to the above aqueous medium and stirred until a homogeneous dispersion was obtained. B Using a cationic flocculant available under the trade name Etz 1260, the above uniform The dispersion was destabilized. The water is then drained and the solids collected on a screen. I met. The composite mat thus produced is dehydrated by pressing and then dried. It was dry. Analysis of the train (white water) shows no fibers of any kind are present. did.

Several dry composite mats were placed in a mold with a cavity depth of 63 mrn, which was then was placed in a furnace and purged with argon to remove oxygen. Then the furnace was adjusted to 1.92 mmHg. A vacuum was applied to a pressure of 1245°C and the temperature was gradually increased to 1245°C. After about 20 minutes , the pressure was increased to 2070 ps i (14,3 MPa) and the temperature was increased to 130 ps/h. ℃ to 140℃. At approximately 890°C, the pressure is 230 ps. i (1.6 MPa) to prevent microcracks during solidification. Cool the furnace further The press was then opened and the fiber shell glass matrix composite was taken out.

There was considerable glass flash on and around the mold.

The sample was removed from the mold and weighed. The weight of the sample is 30.69g and 2.4 It had a density of 62 g/cc.

The composition of the sample was determined by grinding a small portion of the sample. This small amount of grinding The parts were heated to 730°C for 15 minutes in air to burn off the carbon fibers.

There was a weight loss of 27.26%, which was attributed to the carbon fiber. . The burned sample was then repeatedly etched with concentrated nitric acid to remove nickel. I did it. A weight loss of 22.32% occurred. Nickel-coated graphite fibers are It was determined to be 45.02% nickel by weight. This value is 47-5 This corresponds to the manufacturer's report of 0% nickel content.

Various graphite fiber densities from 1.75 g/cc to 1.82 g/cc Volume reported. The observed composition of the complex is as follows.

Weight% Volume%9 Volume%°.

Glass 50.42 52.33 53.17 Graphite fiber 27.26 41.06 40.12 Nickel 22.32 6.61 6.72 1.7 Graphite density taken as 5g/cc; taken as 1.82g/cc Graphite density 7.62 cm x 11.4 mm x 2. A sample of the glass-matrix composite with dimensions of 2 mm was measured using a strain meter. Ta.

Measured average bending strength of 24,100 psi (166 MPa) and 6.18 It exhibited an average bending modulus of 5,0 OOpsi (42,6 GPa). tension The strength is 8,900 ps i (61 MPa) and the tensile modulus is 6.9 It was 20,000 (47.7 GPa). The second sample shows these in a quasi-isotropic manner. The physical properties were shown. This means that the strength is constant in all directions within the plane of the sample being tested. It means something.

The electrical conductivity of this glass matrix composite was 132 (9 cm)-' . This value is very sensitive to the conductivity of metals such as aluminum alloy 380 or nickel. Close to.

The average magnetism of this glass-matrix composite is 15. 85 emu/g (electromagnetic contains the measured saturation value in units/g), which corresponds to a nickel content of 24.38% by weight. (The saturation value of pure nickel is 65 emu/g).

When further examined in a scanning electron microscope, this glass-matrix composite showed It showed good bonding (or wetting) between the fibers and the dispersed fibers. This is the molded surface A small bond was observed. This is due to the high nickel-coated graphite fiber content. It was something that Bonding is improved by using less amount of fiber in the vine.

Further analysis of the composite by biargy dispersive X-ray spectroscopy was carried out on the graphite fiber surface. The dewetting of nickel from This development can be improved by changing the molding conditions. It is believed that it can be easily corrected.

In summary, this example demonstrates the construction of glass matrix composites using aqueous wet laying techniques. This demonstrates the successful production of

Example 2 41 water was thickened with 0.5 g of xanthan gum. Approximately 1.40g of this thickened water 25% solids ethylene-acrylic acid copolymer water dispersion (The Dow Chemical) Commercially available under the trade name PRIMACOR 4983 from Le Co., Ltd. . The solid portion was 20% by weight acrylic acid with a melt index of 3000. ) was added without stirring. Next, approximately 2.02 g of 60% solid polyethylene fibrils Valve (PULPEX from Vercules Truvey Company, Rextal) (commercially available under the trade name E) is pre-dispersed in Brengu. added. After this, 12.97 g of 6.35 mm long quartz fiber (J.P.S. (commercially available under the trademark ASTROQUARTS from Chivens) and 433 g of 9 mm long silicon carbide (SiC) fiber (Dow Corning Co., Ltd.) It is commercially available under the trade name NICALON from Poration. diameter 10 ~15 microns) were added. Stir all ingredients until uniformly dispersed. Ta. Glacial acetic acid was then added to adjust the pH to 4 and destabilize the slurry. destabilization The slurry was drained onto a screen and formed into a mat. Nip this mat Excess water was removed by passing through a tube and then dried. Mats manufactured in this way Each is approximately 1mm thick and has excellent wet and dry strength. Ta.

Four mats were stacked together and heated to a temperature of 200°C and 350 ps i (2, Preforming at a pressure of 4 MPa) melts the binder and partially densifies the mat. It became. If the resulting partially densified mat is reduced to a thickness of 1.5 mm, approximately 25% The theoretical density of the final finish was combined.

Cut 9 round discs of partially densified matte and graphite die set tightly stacked in a mold. Line the die using graphite foil to prevent adhesion. The die set was placed in a vacuum oven and pressed. Argompa the mold The mixture was heated to 600°C for 20 minutes in a high vacuum. The vacuum applied during the cycle is 0,1 The pressure was 3 atm.

After an elapsed time of 20 minutes, a pressure of 113 ps i (779 KPa) was applied.

The temperature was then increased to 1645°C over 60 minutes and the pressure was increased to 8500 psi (58,000 psi). 6 MPa). While maintaining the pressure at 58.6 MPa, the temperature was then increased. The temperature was lowered to 1000″C over 60 minutes, and then the pressure was reduced to 170ps　i　(I　1　 71 KPa). The temperature was reduced to 100°C over a period of 90 minutes. Then, the furnace was opened and the composite pieces were removed from the die set.

The two disk samples according to Example 2 were 2.235 g/cc and 2.241 g/cc. It was found that it has a density of cc. Bulk resistance is 2.0x10' and 2.0XIO It was found to be between 'ohm and cm.

Example 3 401 water was thickened with 2 g of xanthan gum thickener. Average length of 6mm and 8 micron diameter stainless steel fibers (BECK 435 g of vine (commercially available under the trade name INOX) was stirred into a slurry for 5 minutes. , unraveled the fiber bundles. Based on the total amount of purchased stainless steel fibers. It was coated with 8% by weight polyvinyl alcohol. This polyvinyl alcohol is water-soluble It is gender. Next, 17.14 g of 35% solids ethylene-acrylic acid copolymer Powder (trademark PRIMACOR 4990 from The Dow Chemical Company) commercially available under the name Vine) and 35 g of 40% solids polyethylene bulb (bar PULPEX E trademark from Rextal of Cures Turvey Company (commercially available under the name ) was added. Then an average length of 12.7mm and 13mm Magnesia-alumina-silicate glass fiber (Owen) with a diameter of S-2 glass from Zoo Corning Fiberglass Corporation (commercially available under the trade name) were added. Until a uniform dispersion is obtained , stirring was continued during the addition of the ingredients. Finally, add the second slurry to 28% acetic acid 100% The membrane was stabilized by adjusting the pH to acidic.

Place 10 batches of each slurry into a tray with membrane stabilized slurry on the screen. It was made matte by washing. Visual inspection of aqueous media after passing through the screen did. No fibers were observed and the aqueous medium was found to be translucent. These ma The kit was passed through nip rolls to remove excess water and dried. 12 inches x 12 Five mats with dimensions of inch (30°5cm x 30.5cm) were heated to 200”C. Melt the binder by pressing at a pressure of 350 ps i (2.4 MPa). The mat was precoalesced by melting. The resulting precombined composite is about 100 mils ( 0.25 cm) and a density of 25% of the final theoretical density. these Two pieces of the pre-combined cloak were cut into a total of eight pieces. Each is 6 inches x 6 inches It had dimensions of (15.2 cm x 15.2 cm). Stack these 8 pieces into a graphite die set, which was then placed into a vacuum furnace. 200mm After creating a vacuum of Hg, the die set was placed at a pressure of 200 psi (1°38 Pa). The pressure was set and the press heated to 770°C. This pressure and temperature combination is 20 Hold for minutes. The temperature was then increased to 1000°C, at which point the pressure was increased to 1000°C. psi (6,89 MPa). 1000°C and 1000psi The condition was held for 50 minutes. The temperature is then increased at a rate of 25°/min to a temperature of 775°C. During this time, the pressure was maintained at 1000 psi (6,89 MPa). . At a temperature of 775°C, the pressure was reduced to 200 psi (1,4 MPa). I turned off the furnace. After 2 hours, remove the die set from the oven and heat it to 100% in air. Allowed to cool to a temperature of °C.

The hot pressed stack of mat pieces has a density of 2.93 g/cc, which is equal to the theoretical density. I had it. In other words, there were virtually no voids in the stack. heat pump The composite after the removal is composed of 92% by volume glass matrix (magnesia-alumina). slicate) and 8% by volume of reinforcing fibers. This is a supplement of 22% by weight. This corresponds to reinforcing fibers and 78% by weight glass matrix. Apply 3-point bending style The strain gauge measurement of a part of the stack was 19810 psi (136,5 MPa) average bending strength of 146 x 10' psi (100,6 x lO' Pa) It had an average bending modulus of

Ape measured in decibels and megahertz (Mhz) at various frequencies resistance (Ωam) and electromagnetic interference (EMI) determined by the rture Box method. ) The shielding values are shown in the table of the following examples.

Example 4 Example 3 was performed in duplicate with two exceptions. The amount of stainless steel fiber is 32 ．． The amount of glass fiber was increased to 150g. This is 75% by weight Mat consisting of lath fibers, 15% by weight reinforcing fibers and 10% by weight pine material gave a solid component of After heat pressing to create a matrix, this composite has 16 ．． It contained 7% by weight reinforcing fibers and 833% by weight glass matrix.

It consists of 90% glass matrix and 6% stainless steel reinforcing fibers by volume. corresponds to The second method for determining the EMI shield value is Transmission L This is known as the ine method. Using the second method of this example yields the following results: Ta. 30MHz-58dB; 100MHz-58dB; 300MHz-61d B; 1000MHz-7100O The difference between these results and the results in the table is that Ape This is due to the increased accuracy of this method over the rture Box method.

Example 5 Example 3 was performed in duplicate with two exceptions. The amount of stainless steel fiber is 21 ．． The amount of glass fiber was increased to 160g. This is 80% by weight A solid consisting of lath fibers, 10% by weight reinforcing fibers and 10% by weight binder material. gave body composition. After hot pressing to create a glass matrix, the composite is 9 Contains 6 volumes of 96 glass matrix and 4 volumes of I06 stainless steel reinforcing fibers. I was reading. This consists of 11% by weight reinforcing fibers and 89% by weight glass matrix. corresponds to

Specific resistance/shielding data 5 4 0.49 55 37 36 574 6 0.21 68 48 4 4 663 8 0.08 64 58 45 65 Example 6 Example 3 was performed in duplicate with two exceptions. The amount of stainless steel fiber is 16. The amount of glass fiber was increased to 165g. This is 82.5% by weight A matrix containing glass fibers and 7.5% by weight of reinforcing fibers and 10% by weight of binder material. gave the solid component of the cut material. After heat pressing to create a glass matrix , the composite contained 94% by volume glass matrix and 3% by volume SS reinforcing fibers. I was reading. This is 8.3% reinforcing fiber and 91.7% glass matrix by weight. corresponds to

Comparative example A In a comparative method, the method of Example 1 was repeated using glass microspheres instead of glass fibers. A glass-matrix composite was produced as follows.

281 water was adjusted to I) H8 with NH and OH. 24.8% solid ethylene acrylic 112.9 g of sulfuric acid was added as a binder while stirring.

206.6g of glass? BrJX bulb and 50.4g nickel coated graphite fiber Fibers (5 mm length) were added with stirring. Adjust the pH to 4 by adding acetic acid and suspend. The suspension was destabilized. Draining the destabilized suspension using a screen to make a wet mat. This wet mat is passed through a nip roller to dehydrate it. Dry the mat. The dried mat is then heat pressed to form a glass matrix composite. I made a body. Theory of reinforcing fibers in hot-pressed glass matrix composites The amount was calculated to be 17.9% by volume.

The actual content of fibers in the hot-pressed glass matrix composite is 468% by volume. There was.

The discrepancy between theoretical and actual results is due to the loss during mat formation and subsequent dehydration. Loss of glass microspheres during heat pressing of matte as well as glass matrix during heat pressing of matte This is due to the loss of base material. School building losses are reduced by strict control of heat press conditions. Although it is possible to minimize the former loss, it is difficult to minimize it. Ru.

In contrast, Examples 1-6 in the form of matrix material or fiberglass No loss of matrix material or reinforcing fibers was observed. .

Example 7 41 water was thickened with 0.5 g of xanthan gum. Approximately 1.4g of ethylene acrylic The acid copolymer dispersion (0.35 g solid) was added to the thickened water with stirring.

Next, approximately 202 g of PULPEX E™ polyethylene microfiber bulb ( 12] Solid) was pre-dispersed in Brengoo, and this was added. Following this mixture 12.97 g of quartz fibers (average length 6.35 mm, diameter 9 microns) and 4. Uniform dispersion (with 33g of silicon carbide fibers (average length 9mm)) All of the above ingredients were stirred until mixed. Adjust the pH to acidic levels by adding acetic acid. to destabilize the suspension. Drain this slurry onto the screen to matte The cloak was then dehydrated and pressed to dry. Made like this The mats were approximately 1 mm thick and had excellent wet and dry strength.

Four sheets of drying mats were stacked on top of each other at 200"cc) temperature and 350psi ( The mat is molded under a pressure of 2,41 MPa) to melt the binder and partially coalesce the mat. I let it happen. The resulting partially coalesced mat has a thickness of approximately 1.5 mm and a theoretical density of approximately It had a density of 25%.

To cut a round disc of partially densified matte (3.81 cm diameter), graphite - Stacked in die set. A total of 11 of these discs (10,02g) was put into the mold. A graphite foil disk (0,013 cm) is placed between the ram and the material. It was placed in between to prevent sticking after solidification and densification. Heat press furnace die set The mold (die set) was heated to 600℃ in an argon-purged vacuum. °C and a pressure of 70 Bond (40 psi or 276 Pa) for approximately 20 minutes. Heat and hold at this temperature and pressure for 30 minutes to burn off the binder.

The temperature was then increased to 1.645°C for 1 hour, after which the pressure was increased]; 770 bond (1,000 psi or 6.9 MPa). temperature and pressure This combination of forces was held for 15 minutes. The temperature was then lowered to 1,000°C, Then reduce the pressure to 300 Bond (170 ps i or 1.2 MPa) Ta. Finally, the temperature was lowered to 100″C and the furnace was opened.The mold was then opened. The molded article was taken out. The molded article has quasi-isotropic properties and 2.252 g/cc It had density. This corresponds to a residual porosity of 1.1% (theoretical density is 2.2 78 g/cc). No extrusion of quartz was observed. The analysis of complexes The combination is 78% by volume glass matrix and 22% by volume silicon carbide supplement. It was shown that it contains reinforcing fibers.

Comparative Example B Manufacture of lofted composite 160g borosilicate glass microspheres (3 from BQ Industries) commercially available under the trade name 000E) and 40 g of a 9 mm long silicone cap. -bide (SiC) fiber (N1c from Dow Corning Corporation) alon) (commercially available under the trade name alon) was slurried in 41 g of water. pH was adjusted to 8 with NH4OH. Next, 2596 fixed ethylene acrylic acid copolymer mer dispersion (such as PRIMACOR 4983 from The Dow Chemical Company) (commercially manufactured by hand) was added without stirring. Change uniform dispersion All ingredients were stirred until mixed. The slurry was then adjusted to pH 4 with acetic acid. It was destabilized. The destabilized slurry was drained onto the screen to create a mat.

The cloak was passed through nip rolls to remove excess water and dried.

The dried composite was then cut into 3 inch x 3 inch (7.6 cm x 7.6 cm) squares. did. Give enough cloaks to make a total weight of 55.5g and place them in the grapher. This was placed in a furnace and purged with argon to remove oxygen.

The furnace was then evacuated to 28 inches (7 cm) Hg and the temperature was increased for 5 minutes. The temperature was raised to 600°C. After 10 minutes, increase the pressure to 228psi (1.6MPa) and the temperature was increased to 800°C over 20 minutes. Then increase the pressure to 20 Increase to 13 ps i (7 Ma) and increase temperature to 1.175°C for 45 min It was raised to . Then the pressure was further increased to 14.9 MPa) and at this level]5 Hold for 0 minutes, during which time the temperature was reduced to 800°C. Then increase the pressure to 16 60 psi (I 1.4 MPa) and the temperature to 740'C; At this point the pressure was further reduced to 1010 psi (7 MPa). Even more cooling This occurs over a period of 95 minutes, the temperature drops to 200°C, after which the pressure drops to 228p. si (1.6 MPa). After further cooling to 80°C, release the pressure. The press was then opened and the hot press composite was removed from the mold.

The heat press composite is 2. It had a density of 517 g/c. This is 1.1% This corresponds to the residual porosity (theoretical density: 2.545 g/c).

Example 8 1. 0 inch x 10 inch x 0.055 inch (2,54cm x 2.54cm A small piece of the composite of Comparative Example B weighing 2.26 g with dimensions xO, 13 cm) was placed in a furnace. in air to a temperature of 840°C and held at this temperature for 60 minutes. Then the furnace Once cooled, the pieces were removed from the oven. The new dimensions of the composite are 1.003 inches x 1.0 03 inch XO-0723 inch (2,548cm 4 cm). No loss of material was observed. New density is L 89g/c It was c. By dividing the difference in thickness between after heating and before heating by the thickness before heating. Therefore, the loft% was calculated to be 32.

This densified composite uses glass particles rather than glass fibers to create a composite mat. This is then heat pressed to fully coalesce the composite and then applied to the method of the present invention. Therefore, it is not manufactured. However, the densified composite produced according to the present invention Similar results were obtained for other compounds, such as the composite prepared in Example 7.

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Claims (11)

[Claims] 1. The next steps i.e. a. (1) reinforcing fibers, (2) glass fibers, and (3) at least one binder. producing a dilute aqueous slurry having a solid component comprising a powder material; b. destabilizing the aqueous slurry; c. collecting the solid component on a porous support; d. This collected solid is dehydrated and After drying, the reinforcing fibers and glass fibers are tangled and randomly arranged on the surface of the mat. producing a dried composite mat; and e. Stack multiple of these mats or pieces of them and stack them The glass fibers are melted into a continuous glass matrix and the binder material is added between them. heat pressing under conditions sufficient to substantially remove reinforcing fibers and retain the integrity of the reinforcing fibers. Ru; A method for producing a fiber-reinforced glass/matrix composite comprising various steps . 2. Reinforcing fibers with a solid content of 3-35% by volume, glass fibers with a solid content of 45-97% by volume and 1 to 20% by volume of a binder material. 3. The reinforcing fibers have a length of 3 mm to 25 mm, and are made of graphite fibers or metal coatings. Covered graphite fiber, silica fiber, silicon carbide fiber, quartz fiber, ceramic fibers of metal or metal alloys, or mixtures thereof. Method of request 1 or 2. 4. If the reinforcing fibers are stainless steel fibers, nickel-coated graphite fibers, or 4. The method of claim 3, wherein the method is selected from a mixture thereof. 5. Glass fibers include soda-lime glass, borosilicate glass, quartz, and lithium aluminum. Any one of claims 1 to 4 selected from luminium glass or a mixture thereof. or method 1. 6. Binder material is starch, latex dispersion, synthetic or natural polymer The person according to any one of claims 1 to 5, wherein the amount is 1 to 20% by volume. Law. 7. The binder may be ethylene/acrylic acid copolymer, polyolefin fiber, or 7. The method of claim 6, wherein is selected from a mixture thereof. 8. The next additional step is: f. In the absence of pressure, the heat-pressed composite article softens the glass matrix. The reinforcing fibers are heated to a temperature higher than that at which oxidation occurs but lower than the temperature at which the reinforcing fibers deteriorate; and composite articles within this temperature range, based on the quotient of the thickness difference divided by the initial thickness. holding at a temperature sufficient to increase the thickness of the composite article by at least 5%; 2. The method of claim 1, including an additional step. 9. Graphite fiber, metal coated graphite fiber, silica fiber, quartz fiber, 3mm to 25mm selected from lamic fiber, metal fiber, silicon carbide fiber Contains 3 to 35% by solid volume of reinforcing fibers with a length of mm, and the fibers are glass matrix. The glass matrix is almost uniformly distributed and randomly coordinated in the Trix complex. Trix complex. 10. glass fibers are present in an amount of 45-97% by volume, and soda-lime glass; Borosilicate glass, quartz, lithium aluminum silicate glass, or or a mixture thereof. 11. 11. A composite according to claim 9 or 10, wherein the composite has a porosity of 5 to 50%.