IL27439A

IL27439A - Resin and metal filament composite

Info

Publication number: IL27439A
Application number: IL2743967A
Authority: IL
Original assignee: Brunswick Corp
Priority date: 1966-03-14
Filing date: 1967-02-15
Publication date: 1970-12-24
Also published as: DE1704469B2; DE1704469A1; JPS5127715B1; NL6702976A; SE326287B; CH469155A; ES337981A1; FR1513157A; LU53156A1; BE695234A; GB1174292A

Description

•man fr -nini"i ·π PATENTS AND DESIGNS ORDINANCE SPECIFICATION EESiJS AMD MBfii FILAMENT COMPOSITE nana ami «jn¾? ran 33*n» *p a Briwiswick Corporation (a Delaware corporation), 69 Vest Washingto Street, Chicago, Illinois, U.S.A. do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement :- This invention relates to composites and in particular to composites formed of resins and metal filaments.

The structural concept of the reinforcement or other modification of the characteristics of a plastic, or resin, material is well known. Illustratively, wire screening has heretofore been embedded in suitable plastics for use as reinforced window materials and the like. Another known composite structure utilizing metal and plastic in combination is one wherein the metal is provided as a liner, or surface, material on a plastic body. The present invention comprehends an improved composite structure wherein extremely fine metal filaments are provided in the plastic material providing an improved composite structure having characteristics not heretofore available in the art .

Thus, a principal feature of the present invention is the provision of a new and improved composite of metallic fibers embedded in a body of plastic material.

Another feature of the invention is the provision of such a composite wherein the metal fibers have a new and improved surface arrangement providing improved bonding thereof to the plastic material .

A further feature of the invention is the provision of such a composite wherein the metal fibers have a rough nonmachined surface while yet being of extremely small diameter.

Still another feature of the invention is the provision of such a composite wherein the metal fibers have a mean diameter of under approximately 1 mil.

A yet further feature of the invention is the provision of such a composite wherein the fibers comprise continuous filaments.

Another feature of the invention is the provision of such a composite wherein the fibers comprise a nonwoven mat.

Still another feature of the invention is the provision such a composite wherein the fibers comprise a weft knitted fabric.

Yet another feature of the invention is the provision of such a composite wherein the fibers comprise a warp knitted fabric.

Another feature of the invention is the provision of such a composite wherein the fibers comprise a braid.

Still another feature of the invention is the provision of such a composite wherein the fibers are in the form of a roving.

A yet further feature of the invention is the provision of such a composite wherein the fibers are in the form of a yarn.

Yet another feature of the invention is the provision of such a composite wherein the fibers are textured .

Another feature of the invention is the provision of such a composite wherein the fibers are provided in different . structural combinations in the plastic.

A further feature of the invention is the provision of such a composite wherein the fibers are formed of a high electrical resistance material and are in electrical contact with each other in the body to define a resistance heater structure.

Still another feature of the invention is the provision of such a composite wherein the fibers are formed of a metal having a modulus of elasticity of at least approximately 20 million.

A yet further feature of the invention is the provision of such a composite wherein the fibers are formed of a metal having a tensile strength of at leas t approximately 250,000 p.s.i.

Another feature of the invention is the provision of such a composite wherein the plastic material defines a surface zone and the plurality of fibers is disposed at said surface zone.

Yet another feature of the invention is the provision of such a composite wherein the volume ratio of the fibers to the plastic material in the surface zone is at least approximately 40 percent . fibers extending generally perpendicularly to the surface of the zone .

Still another feature of the invention is the provision of such a composite wherein the fibers are provided in the form of a fabric extending generally parallel to the surface of the zone and defining a plurality of interstices, and a plurality of short, generally straight fibers extending in the interstices generally perpendicularly to the surface .

A yet further feature of the invention is the provision of such a composite wherein the fibers comprise a knitted fabric having a rib formed therein.

Another feature of the invention is the provision of such a composite wherein the plastic material defines a tubular body and the fibers comprise a seamless tubular knit structure at the surface zone .

A further feature of the invention is the provision of such a composite wherein the knit fabric has a volume ratio to the plastic material in the zone of at least approximately 40 percent to provide high thermal conductivity therein.

A yet further feature of the invention is the provision of such a composite wherein the tubular knit structure is provided with a helical rib.

Still another feature of the invention is the provision of such a composite wherein the fabric is provided with a rib at the surface of the plastic and said surface follows the contour of the ribbed fabric.

Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein: Figure 1 is a fragmentary perspective view of a composite embodying the invention; Figure 3 is a fragmentary. perspective view of a composite embodying the invention wherein the filaments are provided in the form of a woven fabric; Figure 4 is a fragmentary perspective view of a composite embodying the invention wherein the filaments are provided in the form of a weft knitted fabric; Figure 5 is a fragmentary perspective view of a composite embodying the invention wherein the filaments are provided in the form of a warp knitted fabric; Figure 6 is a fragmentary perspective view of a composite embodying the invention wherein the filaments are provided in the form of a braid; Figure 7 is a fragmentary perspective view of a composite embodying the invention wherein the filaments are provided in the form of a series of spaced layers; Figure 8 is a fragmentary perspective view of a composite embodying the invention wherein the filaments are provided in the form of a series of spaced layers having different fiber arrangements in different layers; Figure 9 is a fragmentary perspective view of a composite embodying the invention wherein the filaments are provided in the form of a roving; Figure 10 is a fragmentary perspective view of a composite embodying the invention wherein the fibers are textured; Figure 11 is a fragmentary perspective view of a composite embodying the Invention wherein the fibers are disposed at a surface zone of the plastic body; Figure 12 is a fragmentary perspective view of a composite embodying the invention wherein the fibers comprise a plurality of fibers extending perpendicular to the surface; Figure 14 is a fragmentary perspective view of a composite embodying the invention wherein the plastic body is tubular and the fibers are in the form of a fabric in the radially inner surface zone of the body; Figure 15 is a fragmentary perspective view of a composite embodying the invention wherein the plastic body is tubular and the fibers are in the form of a fabric in the radially inner surface zone of the body and provided with ribs; and Figure l6 is a fragmentary perspective view of a composite embodying the invention wherein the plastic body is tubular and the fibers define a. continuous element wound circumferentially in the tubular body.

As indicated briefly above, the present invention comprehends an improved composite structure 10 as generally indicated in Figure 1 of the drawing comprising a body of plastic material 11 and a plurality of metal fibers 12 embedded in the plastic body for providing desired properties such as reinforcement of the plastic. Herein, the fibers have an extremely small mean diameter such as under approximately 1 mil, thereby providing a high surface-to-volume ratio of the metallic material for substantially improved bonding of the fibers to the plastic material. Further, fibers 12 herein have a rough nonmachlned surface for further improved bond-ing thereof to the plastic material. Fibers 12 may be formed by suitably drawing a metal rod or wire in a sheath to the desired small diameter and suitably removing the sheath. Thus, fibers 12 herein may comprise short fibers or filaments, the term "filaments" being defined herein in accordance with the American Society for Testing and Materials, Standard Definitions, as fibers of extreme length such as permitting their use directly as yarns.

The invention comprehends the use of any suitable plastic material as the bod of the com osite and thus, for exam le, the both natural and artificial, ceramics, glass, etc. Illustrative examples of suitable plastic materials are epoxy resins, polyimides, tetrafluoroethylene polymers, phenol-formaldehyde, or resorcinol-formaldehyde resins, etc The plastic body may be further provided with other property-affecting materials such as glass fiber.

The fibers 12 may be formed of any suitable workable metal, one excellent example thereof being stainless steel. As indicated above, the fibers are preferably extremely small in diameter such as under 1 mil, an excellent example of such fibers being stainless steel fibers having a diameter of under approximately 12 microns and in the form of filaments. Other suitable constrictible metals may be utilized, such as niobium, nickel, tungsten, iron, aluminum, carbon steel, chrome nickel alloys, etc. The metal material preferably has a relatively high modulus of elasticity, such as at least approximately 20 million, where the composite is intended for use where forces tending to expand or flex the composite are directed thereagainst . Further the fibers are preferably formed of metals having high tensile strength, such as at least approximately 250,000 p.s.i., for Improved reinforcing characteristics. Such high elasticity and tensile strength characteristics are particularly desirable where the plastic body 11 is provided with other reinforcing means such as glass fiber. The composite may be formed by molding the plastic material about the fibers in any suitable conventional molding method as is well known to those skilled in the art.

More specifically, the present invention comprehends the forming of the composite with the fibers in any one of a large number of different physical arrangements. Thus, as shown in Figure 2, a composite 10a embodying the invention may be formed of a plastic body 11 having embedded therein a plurality of metal fibers in the . A wn F ure noth r filaments defining a woven fabric 12b . In Figure , a composite 10c embodying the invention is shown to comprise a plastic body 11 with the metal filaments embedded therein in the form of a weft knitted fabric 12c . In Figure 5, a composite lOd embodying the invention is shown to comprise a plastic body 11 with an embedded warp knitted fabric 12d formed of the above discussed metal filaments. In Figure 6, a composite lOe is shown wherein the metal filaments are provided in the plastic body 11 in the form of a braid 12e . A composite lOq is shown in Figure 9 to include a plur-ality of fibers in the form of roving 12q in the plastic body 11.

The fibers may be provided in the plastic body in a plurality of layers or sheets. In Figure 7* one Illustrative example thereof is shown to comprise a composite 10f wherein three layers 12f of random web arranged fibers (such as shown in Figure 2 ) are provided in the plastic body 11. The different layers may be formed of fibers arranged in different configurations, and in Fig- t ure 8, one such composite structure is illustrated as comprising a composite lOg having a layer 12f of nonwoven web configuration spaced between a pair of sheets 12g of woven fabrics, such as shown in Figure 3 · As will be obvious to those skilled in the art, different ones of the different fiber and filament configurations, such as the nonwoven, woven fabric, knitted fabrics, braid, roving, etc . configurations disclosed herein, may be used in the composite arrangements of Figures 7 and 8 within the scope of the invention.

It has been found that still further improved bonding of the fibers to the plastic body may be obtained herein by textur-izing the fibers. Such fibers may comprise a bulk yarn configuration 12h such as illustrated in Figure 10. As is well known to those skilled in the textile art, such bulk yarns may comprise loopy yarns, high bulk yarns, and crimped yarns. Further, the bulk arn ma be formed as a stretch yarn, either of the torque or of the metallic fibers at the surface of the plastic body for providing to the plastic body, in addition to the reinforcement thereof as discussed above, other desirable properties such as abrasion resistance, whereby the composite may be utilized for structures such as clutch and brake facings and the like, applications wherein other structures may have sliding, rolling, etc., engagement with the surface thereof, etc. Thus, the invention comprehends the provision of a composite illustratively shown in Figure 11 as a composite 101 having a plurality of fibers 12i disposed at the surface zone 13i of the plastic body 11. Thus, composite lOi is generally similar to composite 10, except that the fibers 121 are disposed in a limited surface zone portion of the plastic body. To provide improved abrasion resistance and reinforcement of the plastic, the volume ratio of the fibers 12i to the plastic material in the surface zone 13i is preferably at least approximately 40 percent. The fibers 12i may be provided in the surface zone 13i in any of the different configurations disclosed above Including the non-woven mat, woven fabric, knitted fabrics, braid, and in plural layers of similar or different configurations and may be provided in textured form as desired.

In certain applications, high thermal conductivity through the composite surface zone may be a desideratum. For such applications, the fibers may be formed of metals having high thermal conductivity and arranged in configurations wherein thermal continuity is provided. Where effectively maximum abrasion resistance is desired, the fibers may be formed of high abrasion resistant metals as are well known to those skilled in the metallurgical art, such as stainless steel and the like. Further, suitable fillers such as aluminum phosphate, aluminum oxide, and the like may be used for further improving the abrasion resistance of the lastic material. However, it has been found that b rovidin are relatively small, the improved bonding of the fibers to the plastic herein provides a surface structure which functions substantially in the manner of a continuous metal liner.

Illustratively, it has been found that by providing the metal fibers in the form of a fabric embedded in the surface zone substantially at the surface of the plastic, while some plastic may abrade relatively quickly as a result of abrasion forces generated against the surface, the exposed outer portion of the metal fabric effectively provides the contact surface thereafter while yet a substantial portion of the fibers remains embedded in the plastic thereby effectively precluding separation of the fabric from the plastic body. Where the interstitial distances are made quite small, only the extreme outermost portion of the fibers are exposed so that the fibers may remain embedded in the plastic over at least one-half their circumferential extent, thereby maintain-ing a physical locking of the fibers to the plastic body. In addition, the rough surface of the fibers provides improved maintained retention of the fibers in association with the plastic. Thus, the improved composite structures resulting from the use of the small diameter metal filaments provides an Improved abrasio resistant surface in the composite heretofore not available in the art.

As indicated above, the fibers 12i may be provided in the form of a knit fabric. Such knit fabrics have been found to provide a further improved structural feature in the composite in that in addition to the elasticity of the fiber materials the knit configuration provides further elasticity in the fiber portion of the composite as a function of the stretchability of the knit configuration. Thus, by utilizing the fibers 12i in the form of knit fabric, the composite is capable of substantial flexing or fiber and the like as a portion thereof, as such improved resiliency permits the metal fibers to proximate the elastic range of the glass fibers while yet the metal material may have a substantially higher modulus of elasticity.

Where the fibers are provided as a surface layer material, a number of additional fiber configurations may be utilized. Thus, for example, as shown in Figure 12, a composite 10j may comprise a body of suitable plastic material 11 having a plurality of short fibers 12j embedded in the surface zone 13j to extend perpendicular to the outer surface 14j . In another composite structure as shown in Figure 13* the composite 10k is shown to comprise a body of plastic material having the fibers disposed in the surface zone 13k in the form of a fabric 12k and a plurality of short fibers 12J extending perpendicular to the surface through the interstices of the fabric, thus providing an extremely high ratio of the volume of metal fibers to the plastic material in the surface zone. The perpendicularly disposed fibers provide an improved abrasion resistant surface in that a complete circumferential bond between the fiber and the plastic material is , maintained at all times.

As shown in Figures 14 through 16, the plastic body may be provided in a tubular form. In Figure 14, a composite 10m is o shown to comprise a tubular plastic body 11m having a plurality of fibers 12m providing in the surface zone 13m in the inner surface l4m of the tubular body. The fibers 12m may be provided in any of the forms discussed above, as desired. It has been found that where the fibers are provided in the form of a knit fabric the above discussed improved stretchabllity of the metal fabric provides for improved use of the composite 10m in applications where pressure forces are generated at times within the composite, r4i- of a seamless knit tubular fabric. Illustratively, in forming such a composite, the seamless knit tube may be placed over a mandrel and the plastic body molded thereabout in the conventional manner. The metal fabric may be stretched onto the mandrel so as to provide, in effect, a prestressed reinforcement of the plastic body providing further improved strength in the resultant tubular composite.

In certain applications, it is desirable to provide in the surface of the tubular structure a rib configuration. Illus-tratively, where the application is a ballistic one, the rib may comprise a helical rifling groove. In Figure 15* such a composite 10η is shown to include a plastic body lln wherein the inner surface l n defines a helical rifling groove 15n, the metal fibers being provided in the form of a knit fabric sleeve 12n having knitted therein a helical rib l6n whereby the fabric 12n substantially conforms to the grooved surface l4n . As will be obvious to those skilled in the art, the ribbed fabric l6n may be employed in a composite wherein the inner surface l4n is cylindrical as well as where it defines the groove 15n, as desired. Further, as will be obvious to those skilled in the art, the surface zone in which the fibers are disposed may be the outer circumferential surface zone where abrasion resistant properties are desired in the o outer zone .

The fibers may be distributed throughout the tubular plastic body as well as provided only at the surface zone where further reinforcement of the tubular body is desired. Thus, the plastic body 11 of Figure 1 may comprise a portion of a tubular plastic body. A further fiber configuration may be provided in the tubular plastic body composite structure as shown in Figure 16 wherein the composite lOp comprises a tubular plastic body lip con inuous fila the form of a yarn, or roving, as desired, to provide the Improved reinforcement of the plastic body.

A number of composite properties and specific uses has been discussed above in connection with the disclosed composite structures. As will be obvious to those skilled in the art, the improved composite structure hereof may find many other practical applications. For example, the metal fibers may be provided in the plastic material so as to have electrical continuity through the composite. Thus, the composite may be arranged to define an electrical conductor. Alternatively, by forming the fibers of metal having relatively high electrical resistance, the composite may define an electrical resistance heater structure. It is not intended that the scope of the invention be limited to the specific examples of applications discussed herein, but that the scope of the invention be extended. to all practical applications of the composite structural concepts disclosed herein.

Thus, the present invention comprehends an improved composite structure wherein small diameter metal fibers are provided in a plastic matrix to provide desired improved properties such as strength, abrasion resistance, stretchability, etc. The fibers are effectively positively bonded to the plastic material for improved translation of the fiber properties to the plastic. Further, the improved bonding of the fibers to the plastic provides a highly improved composite surface construction wherein the fibers function substantially in the manner of a sheet liner, while yet are effectively positively retained in association with the plastic body. The fiber material may be selected for imparting further desirable properties to the composite such as high thermal conductivity or electrical resistance. The composite structure is extremely simple and economical of manufacture, while yet providing the above discussed highly desirable features. modifications. Changes, therefore, in the construction and arrange ment may be made without departing from the spirit and scope of the invention as defined in the appended claims .

Claims

HAVING NQW particularly described and ascertained the nature of o¾ijr said invention and in what manner the same is to be performed, Wi declare that what w¾ claim is

1. A composite comprising: a body of plastic material; and a plurality of metallic fibers having a rough nonmachined surface and a mean diameter of under approximately 1 mil embedded in said body for providing reinforcement thereof.

2. The composite of claim 1 wherein said fibers comprise continuous filaments.

3. The composite of claim 1 wherein said fibers comprise continuous filaments in the form of a roving.

4. The composite of claim 1 wherein said fibers comprise continuous filaments in the form of a yarn.

5. The composite of claim 1 wherein said fibers comprise textured continuous filaments.

6. The composite of claim 1 wherein said plurality of fibers comprises a nonwoven mat.

7. The composite of claim 1 wherein said plurality of fibers comprises a woven fabric. a.

8. The composite of claim 1 wherein said plurality of fibers comprises a weft knitted fabric.

9. The composite of claim 1 wherein said plurality of fibers comprises a warp knitted fabric.

10. The composite of claim 1 wherein said plurality of fibers comprises a braid.

11. The composite of claim 1 wherein said fibers are in the form of a combination of at least two configurations including nonwoven mat, woven fabric, weft knitted fabric, warp knitted fabric, and braid configurations.

12. The composite of claim 1 wherein said fibers are formed of a high electrical resistance material and are in electrical contact with each other in said body to define a, resistance heater structure.

13. The composite of claim 1 wherein said fibers are formed of a metal having a modulus of elasticity of at least approximately 20 million.

14. The composite of claim 1 wherein said fibers are formed of a metal having a tensile strength of at least approximately 250,000 p.s.i.

15. The composite of claim 1 wherein said body defines a surface zone and said plurality of fibers is disposed at said surface zone.

16. The composite of claim 1 wherein said body defines a surface zone and said plurality of fibers is diS- posed at said surface zone, the volume ratio of said fibers to said plastic material in said surface zone being at least approximately 40 percent.

17. The composite of claim 15 wherein said fibers comprise continuous filaments.

18. The composite of claim 15 wherein said fibers comprise continuous filaments in' the form of a roving.

19. The composite of claim 15 wherein said fibers comprise continuous filaments in the form of a yarn.

20. The composite of claim 15 wherein said fibers comprise textured continuous filaments.

21. The composite of claim 15 wherein said plurality of fibers comprises a nonwoven mat.

22. The composite of claim 15 wherein said plurality of fibers comprises a woven fabric.

23. The composite of claim 15 wherein said plurality of fibers comprises a weft knitted fabric.

24. The composite of claim 15 wherein said plurality of fibers comprises a warp knitted fabric.

25. The composite of claim 15 wherein said plurality of fibers comprises a braid.

26. The composite of claim 15 wherein said fibers are in the form of a combination of at least two configurations including nonwoven mat, woven fabric, weft knitted fabric, warp knitted fabric, and braid configurations.

27. The composite of claim 15 wherein said fibers are formed of a metal having a modulus of elasticity of at least approximately 20 million.

28. The composite of claim 15 wherein said fibers are formed of a metal having a tensile strength of at least approximately 250, 000 p.s.i.

29. The composite of claim 1 wherein said body-defines a surface zone and said plurality of fibers is disposed at said surface zone, and comprises short generally straight fibers extending generally perpendicularly to the surface of said zone.

30. The composite of claim 1 wherein said body defines a surface zone and said plurality of fibers Is disposed at said surface zone, and comprises a fabric extending generally parallel to the surface of said zone and defining a plurality of interstices, and a plurality of short, generally straight fibers extending in said interstices generally perpendicularly to said surface.

31. The composite of claim 15 wherein said plurality of fibers comprises a knitted fabric having a rib formed therein.

32. . The composite of claim 15 wherein said body is tubular.

33. The composite of claim 15 wherein said body is tubular and said surface zone comprises the radially inner surface zone of the tubular body.

34. 3 . The composite of claim 15 wherein said fibers define a knit metal fabric embedded in said surface zone to provide resistance to abrasion of the composite at said surface zone.

35. The composite of claim 3½ wherein said body is tubular and said fabric comprises a tubular structure.

36. The composite of claim 3^ wherein said fabric has a volume ratio to said plastic material in said zone of at least approximately 40 percent to provide high thermal conductivity therein.

37. The composite of claim 34 wherein said knit metal fabric is provided with a rib.

38. The composite of claim 3 wherein said body is tubular and said fabric comprises a seamless tubular structure.

39. The composite of claim 34 wherein said knit metal fabric is provided with a helical rib.

40. The composite of claim 37 wherein said body is tubular, said fabric comprises a seamless tubular structure, and the surface of said zone follows the contour of the ribbed fabric. Dated this 14th day of February, 1967 e Applicants IWGOLD COHN