US3706614A - Fabrication of composite material by uniting thin fiber coated polymerizable plastic sheets - Google Patents

Fabrication of composite material by uniting thin fiber coated polymerizable plastic sheets Download PDF

Info

Publication number
US3706614A
US3706614A US714901A US3706614DA US3706614A US 3706614 A US3706614 A US 3706614A US 714901 A US714901 A US 714901A US 3706614D A US3706614D A US 3706614DA US 3706614 A US3706614 A US 3706614A
Authority
US
United States
Prior art keywords
fibers
matrix
matrix particles
substrate
particles
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 - Lifetime
Application number
US714901A
Other languages
English (en)
Inventor
Milton E Kirkpatrick
Jo L Reger
Karl P Staudhammer
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.)
Northrop Grumman Space and Mission Systems Corp
Original Assignee
TRW 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 TRW Inc filed Critical TRW Inc
Application granted granted Critical
Publication of US3706614A publication Critical patent/US3706614A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/10—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2913—Rod, strand, filament or fiber
    • Y10T428/2933—Coated or with bond, impregnation or core
    • Y10T428/2938—Coating on discrete and individual rods, strands or filaments
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2913—Rod, strand, filament or fiber
    • Y10T428/2933—Coated or with bond, impregnation or core
    • Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2913—Rod, strand, filament or fiber
    • Y10T428/2933—Coated or with bond, impregnation or core
    • Y10T428/2964—Artificial fiber or filament

Definitions

  • a fiber is defined as an elongated particle of micron-sized diameter, with a length-to-diameter ratio of over to l.
  • the fiber material may be non-crystalline, single crystal, or polycrystalline in nature.
  • a filament differs from a fiber in that its absolute diameter is an order of magnitude greater than that of a fiber.
  • a whisker by definition is a single crystal fiber with a high degree of crystalline perfection which attributes to its ultra-high strengths (above 10 pounds per square inch). Whiskers by nature of their, growth are short, their cross-sections are in the micron range and their length-to-diameter ratio usually ranges from approximately 200 to 10,000.
  • the matrix is a metal, ceramic or plastic.
  • the basic principle for fiber or whisker reinforcement is as follows: fibers or whiskers, having lengths greater than a critical length value, properly aligned to the applied stresses, possessing an adequate concentration, distribute the load throughout the composite more efficiently. Reinforcement of the matrix is accomplished by transfer of the shear stresses between the matrix and the whiskers. The stress on the composite material is consequently transmitted between adjacent whiskers or fibers by the bond with the matrix.
  • the principal role of the matrix is that of a binder for the fibers and whiskers and as a means to transfer stress from one whisker or fiber to the next under any load conditions imposed.
  • Another method according to the prior art consists of mixing a loose slurry of aluminum powder and silicon carbide whiskers, and then extruding the slurry through a fine orifice having a diameter smaller than the length of the whiskers to constrain the whiskers in the direction of flow.
  • the extruded composite is then sintered to unite the whiskers with the aluminum matrix.
  • this method limits the finished composite article to one of small dimensions and restricted shape.
  • a process which includes depositing fibers on a thin substrate so that the fibers are aligned parallel to each other.
  • the substrate serves as a matrix material.
  • a multiplicity of such fiber-coated substrates is then combined by diffusion bonding or other laminating processes so that the substrates diffuse together to produce an integral structure in which the aligned fibers are bound together by the matrix material.
  • FIG. 5 is an enlarged fragmentary, perspective view of a laminated article, with portions of layers removed, in which the fibers in adjacent layers are at 45 degree angles with each other;
  • FIG. 6 is a top plan view showing one step in the process of coating a wire matrix with fibers
  • FIG. 7 is an end view showing a multiplicity of fibercoated wires prior to uniting them into an integral structure
  • FIG. 8 is a sectional view showing an integral structure resulting from bonding the fiber-coated wires of FIG. 7 according to the invention.
  • FIG. 9 is a diagrammatic view, greatly enlarged, illustrating the polarization of fibers and matrix particles in a liquid solution subjected to an electric field
  • FIG. 10 is an enlarged sectional view showing fibers commingled with matrix particles on a substrate
  • FIG. 1 l is an enlarged fragmentary, sectional view of a layered structure, each layer comprising fibers commingled with matrix particles on a substrate prior to bonding of the layers;
  • FIG. 12 is an enlarged, fragmentary sectional view taken at right angles to the section of FIG. 11;
  • FIGS. 13 and 14 are enlarged, fragmentary sectional views of the layered structures of FIGS. 11 and 12, respectively, after bonding of the layers;
  • FIG. 15 is a top plan view illustrating a process of coating a wire with commingled fibers and matrix particles
  • FIG. 16 is an enlarged, fragmentary sectional view showing a bundle of wires coated with commingled fibers and matrix particles, prior to bonding;
  • FIG. 17 is an enlarged, fragmentary sectional view showing the bundle of wires of FIG. 16 after bonding
  • FIG. 1 there is shown an apparatus for coating a thin sheet or foil of matrix material with a micron-size layer of reinforcing fibers or whiskers.
  • the process of coating a single sheet or'wire with aligned fibers is disclosed and claimed in a copending, concurrently filed applicationof J. L. Reger et al, Ser. No.
  • a liquid storage tank holds a liquid suspension 17 of micron-size fibers.
  • the fibers are preferably single crystal fibers of silicon carbide, aluminum oxide, or silicon nitride, commonly known as whiskers. In cross-section, the crystals are threefour-,
  • the diameter of the crystals can be considered as the diameter of the circle drawn tangent to the sides of the polyhedrondefining the cross-section of the crystal.
  • the crystals are usually 100 to 200 microns in length. For use as strength reinforcing ele'ments, they should have a length to diameter ratio of at least 10 to l.
  • the solution in which the fibers are suspended may be polar or non-polar liquids.
  • Amyl acetate is an example of a polar liquid
  • benzeneand toluene are examples of non-polar liquids that are suitable as suspending media.
  • the suspending medium is preferably of low viscosity so that the fibers can freely move therein.
  • a magnetic stirrer or impeller 18 includes a magnetic stirring bar 19 located in the lower section 12.
  • the magnetic stirring bar 19 isactuated by a U-shaped magnet 21 located beneath the storage tank 10 and driven by a motor 23. Rotation of the magnet 21 by the motor 23 causes the stirring bar 19 to rotate.
  • the stirring bar 19 When the stirring bar 19 is rotated, it imparts an upward lift to the fibers and causes them to traverse a honeycomb 20 of glass or plastic tubes or the like located in the intermediate section 14. The fibers thereby exit from the honey-comb 20 and flow into the upper section 16 substantially alongvertical paths.
  • the fibers are subjected to an electric field for the purpose of aligning them parallel to each other along their long dimension.
  • the electric field is provided between a pair of'spaced, parallel, rectangular electrodes 22 and'24 disposed vertically in the upper section 16.
  • the electric field produces lines of force running parallel to each other in the manner exemplified by the dashed lines 26.
  • An alternating voltage source 28 has one side connected to one electrode 24.
  • the other side of the source 28 is connected to the hub of metal roller 30, over which is fed a continuous strip or foil of matrix material 32 from a roll 34 thereof wound on a takeoff reel 36.
  • a takeup reel 38 that is driven slowly by'a small motor (not shown) winds the matrix material 32 after it is coated in a manner to be described.
  • the matrix material 32 traversesa path over the metal roller 30 from which it descends into the liquid suspension 17,
  • rollers 40 and 42 located in the bottom portion of the upper section 16, then vertically upwards in contact with the inner surface of the electrode 22, then out of the .tank 10 over a roller 44, over several smaller rollers 46, and ontothe takeup reel 38.
  • the reels 36 and 38, metal roller 30 .and rollers 44 and 46 are mounted on a support structure 48.
  • -A heater 49 may be provided to dry the fiber-coated matrix material 32 as it traverses the region between the roller 44 and the takeup reel 38.
  • the matrix material 32 may be a metal having a high strength to density ratio, such asaluminum, titanium, or the like, or a light weight metal alloy of similar'propertie's.
  • the invention also has utility in strengthening matrix materials having other desirable properties. For example, columbium and tantalum have. high. melting temperatures, and nickel has good oxidation resistance.
  • the composite of matrix material and fibers or whiskers will have the desirable properties of the matrix material combined with the high strength of the fibers or whiskers.
  • the voltage source 28 may be connected directly to the electrode 22 rather than the roller 32.
  • the roller 32 need not be made of metal or other electrically conducting material.
  • the electrode 22 is smoothly curved at the top and bottom portions thereof so as to avoid any damage to the matrix material 32 from sharp edges.
  • the fibers are identified by the reference numeral 50. It can be seen that the fibers 50 in the liquid suspension 17 are aligned substantially parallel to each other and normal to the surfaces of the electrodes 22 and 24. The alignment of the fibers 50 is along the electric field lines of force existing between the electrodes 22 and 24. To the naked eye the fibers 50 appear as long threads. There is in fact an amount of bunching and overlapping that causes the fibers 50 to link together loosely in the direction of alignment and form thread-like chains.
  • the fibers 50 Being free to move in the liquid suspension, the fibers 50 line up parallel to the electric field. When the electric field reverses polarity during the next half cycle, the fibers 50 also reverse their polarity and accordingly still remain fixed in their same position aligned with the electric field.
  • the electric field is unidirectional rather than alternating, similar alignment of the fibers 50 is obtained, one difference being that there is no reversal of polarity of the electric field in the liquid or on the polarized whiskers 50.
  • the principal reason for preferring an alternating field to an unidirectional field is to prevent any permanent ions present in the suspension from interferring with the deposition of the fibers S0 in the matrix material 32. By alternating the potential on the electrodes 22 and 24, the permanent ions have no preferred direction in which to migrate.
  • the fibers While the fibers are suspended in solution with the electric field applied, they become polarized and aligned as explained above. Being polarized, the fibers in close end-to end adjacency to one another are subjected to electrostatic field forces which tend to attract oppositely charged poles of these fibers. These electrostatic forces are believed to be responsible for the formation of threads of interlinked fibers in the liquid suspension.
  • the fiber-coated foil moves through the drying region indicated by the heater 49, where the solvent evaporates and the binder is solidified.
  • the fibers 50 are deposited on the foil of matrix material 32 as a micron-size layer. Some of the fibers deposit as clumps of three or four, while others deposit singly. Some of the fibers are linked end-to-end, like threads, while others are not connected together. However, if a cross-section is takenat any point across the width of the foil, the section would cut across a great number of the fibers 50.
  • a non-uniform electric field may be produced by making one of the electrodes, say electrode 22, narrower than the other electrode, say electrode 24.
  • the fibers 50 will be attracted .to the narrower electrode 22 if the dielectric constant of the fibers 50 is greater than that of the liquid.
  • the electrode 22 next to the foil need not be as wide as the other electrode 24 and may at first glance appear to be superfluous
  • the electrode 22 by having portions thereof extending beyondthe edges of the foil of matrix material 32, tends to straighten the electrostatic field lines at the edges of the foil and further ensures that the fibers 50 in the edge regions of the foil will be aligned substantially parallel to the whiskers 50 in the central regions of the foil.
  • dielectrophoresis See for example, the article by Herbert A. Pohl entitled The Motion and Precipitation of Suspensoids in Divergent Electric Fields," published in the Journal of Applied Physics, Volume 22, Number 7, July 1951, pages 869-871.
  • a roll of aluminum foil of 0.45 mils thickness and 3 inches width was moved at the rate of 0.35 inches per second through a liquid suspension of silicon carbide whiskers.
  • the solution was amyl acetate containing 0.01 percent by weight of Pyroxylin, which is a DuPont trade name for lacquer grade nitrocellulose binder material.
  • the electrodes 22 and 24 were six inches wide and 2 inches deepin the solution and were places three inches apart. The voltage applied to the electrodes 22 and 24 was 4,000 volts alternating current.
  • a non-conductive matrix material such as plastic
  • the operation of depositing fibers is similar to that describedabove. In this case, however, the voltage is applied directly to both electrodes 22 and 24. The electric field passes through the non-conductive matrix and the fibers are deposited in the same manner. In this case, a binder is probably essential. Glass fibers, or the like, may be used in place of the silicon carbide whiskers.
  • fiber-coated foils of matrix material may be laminated in many layers to form a rigid integral structure of any desired thickness.
  • a portion of such a laminated article is shown in FIGS. 3 and 4, FIG. 3 being a section taken across the width of the laminations, while FIG. 4 is a section taken along the length thereof.
  • any of the well-known methods of forming laminated structures may be used.
  • laminating fibercoated metal foils such processes as diffusion bonding, including hot rolling, may be used.
  • laminating fiber-coated plastic films such bonding techniques may include polymerization or thermoplasticizing.
  • vA process of diffusion bonding has been used to laminate from to 580 layers of aluminum foil reinforced with silicon carbide whiskers.
  • the layers were l060l l 0226 subjected to pressures of from 1,000 to 10,000 pounds per square inch and temperatures of l,000to 1,200 F for to minutes. Higher pressures should be avoided to prevent rupturing of the fibers.
  • the temperature used should be in excess of one-half, but below, the melting temperature of the matrix material.
  • FIGS. 3 and 4 were formed by diffusion bonding of multiplelayers of fiber-coated sheets, it is pointed out that the laminar boundaries or interfaces between the laminar sheets are not clearly discernible. This is due to the fact that the matrix foils are diffused together to form an integral unit of matrix material with the fibers embedded therein disposed in well-defined strata.
  • a laminated structure of aluminum reinforced with silicon carbide whiskers has exhibited a modulus of elasticity of 30 million pounds per square inch as contrasted with a modulus of 10 million poundsper square inch for commercial purity aluminum.
  • the tensile strength of laminations of fiber-reinforced aluminum is 30,000 to'50,000 pounds per square inch as contrasted ,with a tensile strength of 6,000 to 8,000 pounds per square inch of commercial purity aluminum.
  • a true metallurgical bond is produced in which the laminations are mechanically and chemically bonded together.
  • Such a bond is characterized as an adhesive bond. That is, the laminations are bonded together by means of adhesion without the agency of an intermediate constituent.
  • the layers may be laminated so that the fibers run in the same parallel directions, in which case the laminated article may have been preferentially strengthened in one direction.
  • the laminations may be in the form of crossplys in which the fibers in adjacent plys are oriented at 9045 or at smaller angles to each other. In these cases, the reinforcement may be distributed over different angles.
  • FIG. 5 illustrates a laminated article in which the fibers in adjacent plys are at 45 degree angles with each other.
  • FIG. 6 illustrates a process of coating a matrix material in the form of a wire.
  • a wire matrix 52 is located centrally within a cylindrical electrode 54.
  • the fibers 50 line up radially along the electric field lines of force.
  • the fibers 50 deposit on the surface of the wire matrix 52 in a manner similar to that described above in connection with the foil matrix material 32.
  • FIG. 7 shows a multiplicity of fiber-coated wires 52 prior to bonding.
  • FIG. 8 shows a composite article resulting from bonding the fiber-coated wires 52 of FIG. 7.
  • the wires 52 diffuse together into a solid, continuous mass of matrix material 56, with the fibers 50 embedded therein and aligned parallel to each other.
  • the wires 52 may be metal or plastic matrix material.
  • the fibers 50 may be single crystal whiskers, or they may be polycrystalline or non-crystalline as discussed previously.
  • the process of coating a substrate with commingled fibers and matrix particles is disclosed and claimed in copending, concurrently filed application of Karl P. Staudhammer et al, Ser. No. 715,057, entitled Fabrication of Composite Materials by Codeposition of Matrix and Reinforcing Particles, now abandoned.
  • apparatus similar to that of FIG. 1 is used.
  • the storage tank 10 holds a liquid suspension of micron-size fibers and matrix particles.
  • the particlesof matrix material are preferably of sub-micron diameter, and may be particles or powders such as aluminum, nickel, titanium, columbium, or alloys thereof, for example. Alternatively, the matrix particles may be nonmetallic sub-micron particles, such as organic polymers or plastics.
  • the substrate is preferably formed of the same material as that of the matrix particles.
  • the matrix particles will serve to facilitate in the diffusion of matrix material with the fibers, when sheets of fiber-coated matrix material are laminated to form an integral structure, as will be explained.
  • FIG. 9 For a description of how the fibers and matrix particles are caused to deposit on a substrate with the fibers aligned along parallel lines.
  • the fibers are identified by the same reference numeral 50, the matrix particles by the reference numeral 58, and the substrate by the reference numeral 60.
  • the substrate 60 occupies the same position in the apparatus of FIG. 1 as the matrix material 32.
  • the size of the fibers 50 and matrix particles 58 are exaggerated for ease in illustration. It can be seen that the fibers 50 in the liquid suspension 17a are aligned substantially parallel to each other and normal to the surfaces of the electrodes 22 and 24.
  • the alignment of the fibers S0 is along the electric field lines of force existing between the electrodes 22 and 24.
  • Some of the matrix particles 58 bunch together around the ends of the whiskers 50 through the agency of electrostatic forces and cause the fibers 50 to link together loosely in the direction of alingment and form threadlike chains.
  • the negative poles of the matrix particles 58 are attracted to the positive poles of the fibers 50 and the positive poles of the matrix particles 58 are attracted to the negative poles of the fibers 50.
  • the fibers 50 and matrix particles 58 also reverse their polarity and accordingly the fibers 50 and matrix particles 58 still remain fixed in their same position with the fibers 50 aligned with the electric field.
  • the electric field is unidirectional rather than alternating, similar alignment of the fibers 50 and bunching of the matrix particles 58 is obtained, one difference being that there is no reversal of polarity of the electric field in the liquid or on the polarized fibers 50 and matrix particles 58.
  • the principal reason for preferring an alternating field to a unidirectional field is to prevent any permanent ions present in the suspension from interfering with the deposition of the fibers 50 and the matrix particles 58 on the substrate 60.
  • the permanent ions have no preferred direction in which to migrate.
  • aligned fibers 50 attach themselves to the substrate 60 throughout its immersed length. As the substrate 60 moves out of the liquid suspension 17a, the fibers 50, and matrix particles 58, breaking through the liquid surface, hang onto the substrate 60 and by surface forces attach themselves vertically to the substrate 60 to assure the desired parallel alignment of the fibers 50.
  • the fibers 50 and matrix particles 58 are deposited on the substrate 60 as a micron-size layer. Some of the fibers 50 deposit as clumps of three or fouror more, with matrix particles 58 attached thereto, while others deposit singly. Some of the fibers 50 are linked end to end with the matrix particles 58, like threads, while others are not connected together. However, if a cross section is taken at any point across the width of the substrate 60, the section would cut across a great number of the fibers 50 and matrix particles 58. Ideally, the greater bulk of the fibers 50 should deposit as a substantially uniform layer of several whiskers deep, as shown in FIG. 10.
  • the fibers 50 and matrix particles 58 will be attracted towards the electrode where the field concentration is lower.
  • a non-uniform electric field may be produced by making one of the electrodes, say electrode 22, narrower than the other electrode, say electrode 24. In such case, the fibers 50 and matrix particles 58 will be attracted to the narrower electrode 22 if the dielectric constants of the fibers 50 and matrix particles 58 are greater than that of the liquid.
  • a roll of aluminum foil of 0.45 mils thickness and 3 inches width may be moved at a rate of 0.35 inches per second through a liquid suspension of aluminum carbide whiskers and aluminum matrix particles.
  • The, solution may be amyl acetate containing .01 percent weight of Pyroxylin binder material.
  • the aluminum matrix particles may be equal to or less than 44 microns in diameter but are preferably less than a micron in diameter.
  • the electrodes 22 and may be six inches wide and two inches deep in the solution and placed three inches apart.
  • the voltage applied to the electrodes 22 and 24 may be 4,000 volts alternating current.
  • a non-conductive substrate such as plastic
  • the operation of depositing fibers and matrix particles is similar to that described above. In this case, however, the voltage is applied directly to both electrodes 22 and 24. The electric field passes through the non-conductive substrate and the fibers or whiskers and matrix particles are deposited in the same manner. In this case, a binder is probably essential.
  • Substrates made of matrix material and coated with fibers 50 and matrix particles 50 may be laminated in many layers to form a rigid integral structure of any desired thickness. Any of the well-known methods of forming laminated structures may be used, such as those previously described in connection with the deposition of fibers above.
  • FIGS. 11 and 12 show a portion of a layered structure, prior to bonding, each layer of which is similar to the structure of FIG. 10.
  • Each layer includes a substrate 50 of matrix material coated with fibers 50 com- I060l 1 022B mingled with matrix particles 58.
  • the dimensions are greatly exaggerated for ease in illustration and only a few layers are shown, it being understood that an actual layered structure will include several hundred layers.
  • the substrate 60 of matrix material may be five microns thick, the fibers or whiskers two microns in diameter, and the matrix particles 58 may be less than a micron in diameter.
  • the thickness of the fiber layer may be ten. fibers thick, thereby providing a ratio of four to one between the thickness of the fiber layer and the thickness of the substrate 60.
  • FIGS. 11 and 12 show a laminated structure after the layers are bonded according to techniques previously referred to, such as diffusion bonding.
  • the application of heat and pressure acts to squeeze the fibers 50 and matrix particles 58 together and to cause the matrix particles 58 to fuse together in the spaces between the fibers 50.
  • the substrate 60 of matrix material fuses with the matrix particles 58, forming a solid continuous body of matrix material 61 in which the fibers 50 are embedded.
  • the fibers 50 are squeezed into layers, identified by a thickness 62, separated by a layer of matrix material, identified by a thickness 64 which represents the position formerly occupied by the substrate 60.
  • a thickness 62 which represents the position formerly occupied by the substrate 60.
  • the ratio of the thickness 62 to thickness 64 has been reduced to about three to one.
  • the fibers 50 occupy the major portion of the total volume of the laminated structure, and the matrix particles 58 have filled in the voids previously existing between the fibers 50.
  • a process of diffusion bonding may be used to laminate from 100 to 600 layers of aluminum foil substrates, reinforced with silicon carbide whiskers commingled with aluminum sub-micron matrix particles.
  • the layers are subjected to pressures of from 1,000 to 10,000 poundsper square inch and temperatures of l,000 to l,200 F for 5 to 10 minutes. Higher pressures should be avoided to prevent rupturing of the fibers or whiskers.
  • the temperature used should be in excess of one-half, but below, the melting temperature of the matrix material.
  • a laminated structure of aluminum foil substrates reinforced with silicon carbide whiskers commingled with aluminum submicron matrix particles can be expected to exhibit a modulus of elasticity of 30 million pounds per square inch as contrasted with a modulus of 10 million pounds per square inch for commercial purity aluminum.
  • the tensile strength of laminations of fiber reinforced aluminum is expected to be 30,000 to 50,000 pounds per square inch as contrasted with a tensile strength of 6,000 to 8,000 pounds per square inch of commercial purity aluminum.
  • a true metallurgical bond is produced in which the laminations are mechanically and chemically bonded together.
  • Such a bond is characterized as an adhesive bond. That is, the laminations are bonded together by means of adhesion without the agency of an intermediate constituent.
  • the layers may be laminated so that the fibers or whiskers run in the same parallel directions, in which case the laminated article may have been preferentially strengthened in one direction.
  • the laminations may be in the form of cross-plys in which the fibers in adjacent plys are oriented at 45, or at smaller angles to each other. In these cases, the reinforcement may be distributed over different angles.
  • FIG. 15 illustrates a process of coating a matrix material in the form of a wire.
  • a wire matrix 66 is located centrally within a cylindrical electrode 68.
  • the fibers 50 and matrix particles 58 line up radially along the electric field lines of force.
  • the fibers 50 and matrix particles 58 deposit on the surface of the wire matrix 66in a manner similar to that described above in connection with the foil matrix material or substrate 60.
  • FIG. 16 shows a multiplicity or bundle of matrix wires 66 coated with fibers 50 and matrix particles 58 prior to bonding.
  • FIG. 17 shows a composite article resulting from bonding the coated wires 66 of FIG. 16. As illustrated in FIG. 17, the wires 66 diffuse together into a solid, continuous mass of matrix material 70, with the fibers 50 embedded therein and aligned parallel to each other. It is understood that the matrix wires 66 and matrix particles 58 may be metal or plastic matrix material. Also the fibers 50 may be single crystal whiskers, or they may be polycrystalline or non-crystalline as discussed previously.
  • an alternative method may be used for depositing fibers and matrix particles on a substrate.
  • the fibers and matrix particles are deposited on a substrate in the form of an endless belt to produce a film of fibers united with matrix particles and the film is then stripped away from the substrate.
  • An endless belt 72 is driven by a roller 74, over a second roller 76, then over a third and fourth roller 78 and 80 in the liquid suspension 17a, following which the belt 72 slides across the electrode 22 and over a fifth and final roller 82.
  • the belt 72 may be made of metal, and preferably is coated with a plastic, such as Teflon, to give it a sliding surface from which the deposited film can easily be removed.
  • the matrix particles in the liquid suspension are preferably made of polymerizable or thermoplastic materials, such as polyethylene, polyurethanes, epoxies, and polyimides, for example.
  • the binder used in the liquid suspension 17a may be a polymerizable material.
  • the aligned fibers commingled with matrix particles are deposited on the moving belt 72 in the same manner as described previously in connection with the apparatus of FIG. 1.
  • the fibers and commingled matrix particles form a loosely bound film 84 loosely attached to the belt 72 by means of the binder material.
  • the deposited film 84 is subjected to radiation from a lamp 86 to dry the solvent from the liquid suspension material 17a and polymerize the matrix particles and/or the binder material and form a coherent film of aligned fibers embedded in polymerized plastic.
  • the radiation from the lamp 86 may be infrared, ultravoilet, or other polymerizing radiation.
  • the polymerized film 84 is then removed from the endless belt 72 by means of a doctor blade 88 and rolled on a takeup reel 90.
  • laminated structures of polymerized film 84 may be formed of any desired thickness, only three layers being shown for ease in description.
  • Each layer of film 84 includes aligned v fibers 92 embedded in polymerized matrix material 94.
  • the layers or films 84 are joined together by a layer of adhesive 96, which may be the same material as the matrix material or a different material.
  • the matrix particles and/or binder material in the film 84 deposited on the moving belt 72 may be partially polymerized by the radiation from the lamp 86 prior to removal by the doctor blade 88. Partially polymerized films 84 may then be stacked in layers as shown in FIG. 20 without the aid of adhesive material, and the layered structure may be further polymerized to produce a finished fiber-reinforced article of desired thickness.
  • the film 84 deposited on the belt 72 may be subjected to heat from the lamp 86 solely to remove solvent from the binder material without polymerizing either the binder material or matrix particles.
  • the film 84a after removal by the doctor blade 88 may consist of polymerizable matrix particles 98 and aligned fibers 92 held together by binder material 100.
  • the films 84a may be stacked together as shown and subjected to heat and pressure to polymerize the matrix particles 98 and decompose the binder material.
  • the finished article will consist of aligned fibers 92 embedded in a mass of polymerized matrix material 102.
  • the apparatus of FIG. 1 may be used to deposit metal matrix particles commingled with fibers on a substrate that is of a different material from the matrix particles. Thereafter, during the laminating process, the substrate material may be removed by vacuum evaporation in the case of a metal substrate, or by thermal decomposition, in the case of a plastic or non-metallic substrate.
  • the substrate material may be removed by vacuum evaporation in the case of a metal substrate, or by thermal decomposition, in the case of a plastic or non-metallic substrate.
  • aluminum matrix particles and fibers may be deposited on a foil made of lead 'or other metal that vaporized in vacuum at a lower temperature than the aluminum.
  • the foils coated with fibers and aluminum particles are then stacked together and placed in a vacuum furnace where the stacked layers are subjected to heat and mechanical pressure.
  • the lead substrates vaporize, and the vapor therefrom is exhausted, and the aluminum particles merge together by diffusion bonding into a solid continuous matrix containing the aligned fiber
  • a method of fabricating composite materials comprising:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Mechanical Engineering (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Laminated Bodies (AREA)
  • Reinforced Plastic Materials (AREA)
US714901A 1968-03-21 1968-03-21 Fabrication of composite material by uniting thin fiber coated polymerizable plastic sheets Expired - Lifetime US3706614A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US71490168A 1968-03-21 1968-03-21

Publications (1)

Publication Number Publication Date
US3706614A true US3706614A (en) 1972-12-19

Family

ID=24871911

Family Applications (1)

Application Number Title Priority Date Filing Date
US714901A Expired - Lifetime US3706614A (en) 1968-03-21 1968-03-21 Fabrication of composite material by uniting thin fiber coated polymerizable plastic sheets

Country Status (3)

Country Link
US (1) US3706614A (enrdf_load_stackoverflow)
DE (1) DE1914318A1 (enrdf_load_stackoverflow)
GB (1) GB1259625A (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4664768A (en) * 1985-03-28 1987-05-12 Westinghouse Electric Corp. Reinforced composites made by electro-phoretically coating graphite or carbon
US5288537A (en) * 1992-03-19 1994-02-22 Hexcel Corporation High thermal conductivity non-metallic honeycomb
US5466507A (en) * 1993-10-14 1995-11-14 Hexcel Corporation High thermal conductivity non-metallic honeycomb with laminated cell walls
US5470633A (en) * 1993-10-14 1995-11-28 Hexcel Corporation High thermal conductivity non-metallic honeycomb with optimum pitch fiber angle
US5527584A (en) * 1993-10-19 1996-06-18 Hexcel Corporation High thermal conductivity triaxial non-metallic honeycomb
US5750244A (en) * 1989-05-01 1998-05-12 Christensen; Richard M. High strength polymeric-fiber composites
US6607645B1 (en) 2000-05-10 2003-08-19 Alberta Research Council Inc. Production of hollow ceramic membranes by electrophoretic deposition
US20050126676A1 (en) * 2002-03-29 2005-06-16 Hssa Sweden Ab Arrangement and methods for the manufacture of composite layer structures
US20060201868A1 (en) * 2005-03-11 2006-09-14 Simmons Blake A Methods and devices for high-throughput dielectrophoretic concentration
US20110052898A1 (en) * 2009-09-02 2011-03-03 General Electric Company Composite material with fiber alignment
US20170218532A1 (en) * 2014-10-29 2017-08-03 Kechuang Lin Porous materials and systems and methods of fabricating thereof

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2343775A (en) * 1942-12-12 1944-03-07 Polaroid Corp Process for forming sheets or films of light-polarizing material
US2744041A (en) * 1955-06-06 1956-05-01 Us Rubber Co Adhesive sheeting
GB760530A (en) * 1953-07-27 1956-10-31 Libbey Owens Ford Glass Co Method and apparatus for the continuous production of reinforced plastic articles
US3082138A (en) * 1957-09-10 1963-03-19 Lindeman Naur Production of sheet material
US3244572A (en) * 1961-07-13 1966-04-05 Goodyear Tire & Rubber Production of plastic sheet containing short lengths of filamentary material
US3386840A (en) * 1964-11-24 1968-06-04 Monsanto Co Article containing silicon carbon fibers
US3406053A (en) * 1964-06-01 1968-10-15 Whittaker Corp Adhesive composition
US3445361A (en) * 1966-05-04 1969-05-20 Horizons Research Inc Whisker reinforced composite materials produced by electrophoretic deposition
US3449230A (en) * 1966-11-08 1969-06-10 Turner Brothers Asbest Manufacture of asbestos products
US3467588A (en) * 1965-10-24 1969-09-16 Vitro Corp Of America Production of uniformly gradated coatings
US3476641A (en) * 1965-06-01 1969-11-04 Gen Technologies Corp High-strength single crystal whisker paper composites and laminates
US3481822A (en) * 1966-11-14 1969-12-02 Monsanto Res Corp Glass reinforced epoxy anhydride polymers

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2343775A (en) * 1942-12-12 1944-03-07 Polaroid Corp Process for forming sheets or films of light-polarizing material
GB760530A (en) * 1953-07-27 1956-10-31 Libbey Owens Ford Glass Co Method and apparatus for the continuous production of reinforced plastic articles
US2744041A (en) * 1955-06-06 1956-05-01 Us Rubber Co Adhesive sheeting
US3082138A (en) * 1957-09-10 1963-03-19 Lindeman Naur Production of sheet material
US3244572A (en) * 1961-07-13 1966-04-05 Goodyear Tire & Rubber Production of plastic sheet containing short lengths of filamentary material
US3406053A (en) * 1964-06-01 1968-10-15 Whittaker Corp Adhesive composition
US3386840A (en) * 1964-11-24 1968-06-04 Monsanto Co Article containing silicon carbon fibers
US3476641A (en) * 1965-06-01 1969-11-04 Gen Technologies Corp High-strength single crystal whisker paper composites and laminates
US3467588A (en) * 1965-10-24 1969-09-16 Vitro Corp Of America Production of uniformly gradated coatings
US3445361A (en) * 1966-05-04 1969-05-20 Horizons Research Inc Whisker reinforced composite materials produced by electrophoretic deposition
US3449230A (en) * 1966-11-08 1969-06-10 Turner Brothers Asbest Manufacture of asbestos products
US3481822A (en) * 1966-11-14 1969-12-02 Monsanto Res Corp Glass reinforced epoxy anhydride polymers

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Kirk Othmer Encyclopedia of Chemical Technology Vol. 8 (2nd. Edition) pp. 23 36 (1965). *
Pohl, J. Applied Physics, 22 (No. 7), pp. 869 871 (1951). *

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4664768A (en) * 1985-03-28 1987-05-12 Westinghouse Electric Corp. Reinforced composites made by electro-phoretically coating graphite or carbon
US5750244A (en) * 1989-05-01 1998-05-12 Christensen; Richard M. High strength polymeric-fiber composites
US5288537A (en) * 1992-03-19 1994-02-22 Hexcel Corporation High thermal conductivity non-metallic honeycomb
US5466507A (en) * 1993-10-14 1995-11-14 Hexcel Corporation High thermal conductivity non-metallic honeycomb with laminated cell walls
US5470633A (en) * 1993-10-14 1995-11-28 Hexcel Corporation High thermal conductivity non-metallic honeycomb with optimum pitch fiber angle
US5527584A (en) * 1993-10-19 1996-06-18 Hexcel Corporation High thermal conductivity triaxial non-metallic honeycomb
US6607645B1 (en) 2000-05-10 2003-08-19 Alberta Research Council Inc. Production of hollow ceramic membranes by electrophoretic deposition
US7951258B2 (en) * 2002-03-29 2011-05-31 Lamera Ab Arrangement and methods for the manufacture of composite layer structures
US20050126676A1 (en) * 2002-03-29 2005-06-16 Hssa Sweden Ab Arrangement and methods for the manufacture of composite layer structures
US20060201868A1 (en) * 2005-03-11 2006-09-14 Simmons Blake A Methods and devices for high-throughput dielectrophoretic concentration
US7666289B2 (en) 2005-03-11 2010-02-23 Sandia Corporation Methods and devices for high-throughput dielectrophoretic concentration
US20090045064A1 (en) * 2005-03-11 2009-02-19 Simmons Blake A Methods and Devices for High-Throughput Dielectrophoretic Concentration
US20110052898A1 (en) * 2009-09-02 2011-03-03 General Electric Company Composite material with fiber alignment
CN102001861A (zh) * 2009-09-02 2011-04-06 通用电气公司 带有纤维排列的复合材料
US7951464B2 (en) * 2009-09-02 2011-05-31 General Electric Company Composite material with fiber alignment
US20170218532A1 (en) * 2014-10-29 2017-08-03 Kechuang Lin Porous materials and systems and methods of fabricating thereof

Also Published As

Publication number Publication date
DE1914318A1 (de) 1970-08-27
GB1259625A (enrdf_load_stackoverflow) 1972-01-05

Similar Documents

Publication Publication Date Title
US3706614A (en) Fabrication of composite material by uniting thin fiber coated polymerizable plastic sheets
US4560603A (en) Composite matrix with oriented whiskers
US3829327A (en) Carbon paper
US3930091A (en) Unidirectional webbing material
Liu et al. Structural and magneto-transport properties of electrodeposited bismuth nanowires
US3494382A (en) Chemical products and processes
US4865933A (en) Battery grid structure made of composite wire
US2723705A (en) Method and apparatus for making reinforced plastic laminates
US5070606A (en) Method for producing a sheet member containing at least one enclosed channel
US20140186550A1 (en) Methods for the production of aligned carbon nanotubes and nanostructured material containing the same
US20070298253A1 (en) Transparent Conductive Carbon Nanotube Film and a Method for Producing the Same
US5260124A (en) Intercalated hybrid graphite fiber composite
CN106575573A (zh) 能量储存器件及其制造方法
US3881522A (en) Unidirectional webbing material
EP0344318A1 (en) Nonwoven fabric and apparatus for manufacturing same
US3919028A (en) Method of making unidirectional webbing material
DE2616394B2 (de) Verfahren zur Herstellung von supraleitfähigen^ aus einer Kunststoff- oder Glas-Matrix mit eingelagerten Teilchen bestehendem Material
FR2570646A1 (fr) Procede de preparation de materiaux composites a elements de renforcement orientes et produits obtenus
US3717443A (en) Zirconium diffusion barrier in titanium-silicon carbide composite materials
DE2345366A1 (de) Faserbeschichtetes thermoplast
US3876389A (en) Composite material, inclusions thereof, and method therefor
US10724163B2 (en) Nanofiber fabric
US3505177A (en) Electroforming process
KR880005317A (ko) 구리피복 섬유의 연속 실 또는 토우 그 생산 방법 및 그러한 실 또는 토우로 부터 만들어진 복합체
DE1914317A1 (de) Verfahren zur Herstellung eines als Verbundstoff ausgebildeten Halbfertigerzeugnisses