Curved composite golf club shaft and method of manufacturing a curved composite golf club shaft

Abstract

The present disclosure relates to curved composite golf club shafts and methods of making curved composite golf club shafts. Disclosed herein is a lightweight, low-torque, composite golf club shaft having a curved tip and methods of making such a golf club shaft. Some methods include using a pre-bent rigid tube that remains within the finished composite shaft to support its curved tip structure. Other methods require the use of a core (which may be flexible and / or dissolvable) that supports the composite shaft precursor as it is placed into a forming mold to form the curved tip. These cores can be removed at the end of the bending process. Still other methods incorporate the use of an air bladder to provide support for the shaft tip as it is subjected to forming forces.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Patent Application No. 17 / 525,892, U.S. Patent Application No. 17 / 497,643, and U.S. Patent Application No. 17 / 497,059. U.S. Patent Application No. 17 / 525,892 is a continuation-in-part of U.S. Patent Application No. 17 / 497,643, filed on October 8, 2021, and is also a continuation-in-part of U.S. Patent Application No. 17 / 497,059, filed on October 8, 2021, and the disclosures of each of which are hereby incorporated by reference herein in their entirety.

[0003] STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0004] not applicable Technical Field

[0005] The present invention relates to a lightweight, low torque, composite golf club shaft having a curved tip that exceeds a frequency threshold, and a method of making such a composite golf club shaft. Background Art

[0006] Prior art graphite golf club shafts are constructed by cutting prefabricated graphite sheets, applying them to a contoured metal shaft, and then rolling the shaft. This process is repeated to create a multi-layer shaft. During the curing step, a layer of cellophane tape is applied to provide pressure to the graphite. The shaft is then placed in an oven and cured. The shaft is then placed on a centerless grinder to finalize the shape and remove any remaining tape. It is then cut to length, painted, and decorated with decals.

[0007] The rolling, curing, and grinding processes of this prior art method only allow for the production of straight golf club shafts, which is undesirable because golfers generally prefer curved tip shafts, especially for putters, so that they can generate sufficient shaft flex during their swing. The golf industry has addressed this problem by manufacturing dual-matrix shafts, in which a curved tip made of steel is bonded to a straight graphite shaft. However, this configuration increases the cost and time of the shaft manufacturing process, and the combined product is heavier than a fully composite shaft. Therefore, there is a need for improved curved tip golf club shafts, and improved methods for manufacturing such shafts. Summary of the Invention

[0008] One aspect of the present invention is a fully composite shaft having a curved tip. The bend may include one or more bends. The shaft may be hollow, completely solid, or have both hollow and solid portions. The composite shaft may be comprised of graphite laminates that may be oriented in any direction and may be unidirectional, woven, or braided. The shaft may be stepped or stepless, such as tapered, and may have parallel or tapered tips. The shaft may be used for cupped hosels and spud hosels. The shaft is lighter than steel, has low torque values, and meets minimum frequency measurements.

[0009] Other aspects of the present invention are methods for making composite shafts with curved tips. In one method, a thin-walled aluminum tube is bent into the desired profile, and a graphite sheet is wrapped around the tube. Adhesive tape is applied to provide pressure during a standard curing process. At the end of the process, the aluminum tube remains in the finished shaft. In another method, the graphite sheet is wrapped around a removable core, which can be made of an elastic material such as rubber, foam, or salt. The core can extend the entire length of the shaft or only the length of the curved portion. The shaft is then heated to a temperature above the glass transition temperature, Tg, and the tip of the shaft is placed in a mold to bend it. The core is ultimately removed from the shaft to create a hollow shaft, although in alternative embodiments, the core can remain in the final product. In yet another method, a balloon mold can be used to achieve the desired tip curvature. In another method, an airbag is placed at the tip of a tapered rod and covered with a removable straight tip. A graphite sheet is applied to the rod and partially cured according to prior art methods. When the portion is still above Tg, the removable straight tip is removed, the rod shaft is formed into a mold at the tip, and the airbag is inflated. After curing, the airbag is deflated and the rod is removed.

[0010] Yet another aspect of the present invention is a method of manufacturing a golf club shaft, comprising the steps of providing a curved tube comprised of a rigid material, the curved tube having a first shape; inserting a removable mandrel into the curved tube; cutting a composite material into a plurality of composite pieces; wrapping the composite pieces around the curved tube to form a first precursor shaft; wrapping adhesive tape around the first precursor shaft; curing the first precursor shaft to form a second precursor shaft; removing the mandrel from the second precursor shaft; and applying an appearance feature to the second precursor shaft to create a final golf club shaft. In some embodiments, the first shape may include a first bend having a first bend angle of 10 to 30 degrees, and may further include a second bend having a second bend angle, wherein the second bend angle is 10 to 30 degrees. In further embodiments, the first bend angle may be 20 to 25 degrees, and the second bend angle may be 12 to 16 degrees. In another embodiment, the method may further include wrapping a tubular composite around the first precursor shaft, which may occur between wrapping the adhesive tape around the first precursor shaft and curing the first precursor shaft. In any of these embodiments, the rigid material may be selected from the group consisting of a metal alloy and a polymer, and the composite material may be selected from the group consisting of a prepreg material and a tubular braided composite. Also in any embodiment, the final golf club shaft may have a torque of less than 1.5 degrees and a frequency greater than 360 cycles / minute.

[0011] Another aspect of the present invention is a method for manufacturing a golf club shaft, comprising the steps of cutting a composite material into a plurality of composite pieces; joining a flexible core to a shaft comprised of a rigid material; wrapping the composite pieces around the flexible core and shaft combination to form a first precursor shaft; rolling the first precursor shaft to form a straight second precursor shaft; wrapping adhesive tape around the second precursor shaft; curing the second precursor shaft to form a third precursor shaft having a tip; placing the tip in a forming mold while the tip is at a temperature above Tg; bending the tip within the forming mold to form a fourth precursor shaft having at least one bend; curing the fourth precursor shaft; removing the flexible core and shaft combination from the fourth precursor shaft; and applying appearance features to the fourth precursor shaft to create the final golf club shaft.

[0012] In some embodiments, the at least one bend may include a first bend having a first bend angle of 10 to 30 degrees, and may further include a second bend having a second bend angle of 10 to 30 degrees. In further embodiments, the first bend angle may be 20 to 25 degrees, and the second bend angle may be 12 to 16 degrees. In any of these embodiments, the final golf club shaft may have a torque of less than 1.5 degrees and a frequency greater than 360 cycles per minute. In any embodiment, the rigid material may be selected from the group consisting of a metal alloy and a polymer, and the composite material may be selected from the group consisting of a prepreg material and a tubular braided composite.

[0013] Yet another aspect of the present invention is a method for manufacturing a golf club shaft, comprising the steps of cutting a composite material into a plurality of composite pieces; providing a core; wrapping the composite pieces around the core to form a first precursor shaft; rolling the first precursor shaft to form a straight second precursor shaft; wrapping adhesive tape around the second precursor shaft; curing the second precursor shaft to form a third precursor shaft having a shaft tip; placing the shaft tip in a forming mold while the shaft tip is at a temperature above Tg; bending the shaft tip within the forming mold to form a fourth precursor shaft having at least one bend; curing the fourth precursor shaft; and applying appearance features to the fourth precursor shaft to create a final golf club shaft.

[0014] In some embodiments, the method may further include the step of mounting a metal cylinder on the tip of the core, which step may occur between the step of providing the core and the step of wrapping the composite member around the core to form a first precursor shaft, and the final golf club shaft may include a recess in the shaft tip formed by the metal cylinder. In an alternative embodiment, the method may further include the step of drilling the inner diameter of the shaft tip to form a recess in the shaft tip, which step may occur between the step of curing the fourth precursor shaft and the step of applying appearance features to the fourth precursor shaft to create the final golf club shaft.

[0015] In any embodiment, the at least one bend may include a first bend having a first bend angle of 10 to 30 degrees, and may further include a second bend having a second bend angle of 10 to 30 degrees. In further embodiments, the first bend angle may be 20 to 25 degrees, and the second bend angle may be 12 to 16 degrees. In any embodiment, the final golf club shaft may have a torque of less than 1.5 degrees and a frequency greater than 360 cycles / minute.

[0016] After briefly describing the present invention, those skilled in the relevant art will recognize the above and further objects, features and advantages of the present invention from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a top plan view of a first embodiment of a golf club shaft according to the present invention.

[0018] Figure 2 yes Figure 1 An enlarged side plan view of the circled portion of the embodiment shown in FIG.

[0019] Figure 3 It is a top plan view of a second embodiment of a golf club shaft according to the present invention.

[0020] Figure 4A and 4B yes Figure 3 A side plan view of the circled portion of the embodiment shown in FIG.

[0021] Figure 5 is a process flow diagram illustrating the first method of the present invention.

[0022] Figure 6 is used Figure 5 A description of a golf club shaft created by the method described in the accompanying drawings.

[0023] Figure 7 is a process flow diagram illustrating the second method of the present invention.

[0024] Figure 8 is Figure 7 A golf club shaft precursor is created during the method described.

[0025] Figure 9 is used Figure 7 A description of the final golf club product created by the method described.

[0026] Figure 10 is a process flow diagram illustrating the third method of the present invention.

[0027] Figure 11A and 11B is Figure 10 A description of a golf club shaft precursor created during the method presented.

[0028] Figure 12 is used Figure 10 A description of the final golf club product created by the method described.

[0029] Figure 13is a process flow diagram illustrating the fourth method of the present invention.

[0030] Figures 14 and 14B are Figure 13 A description of a golf club shaft precursor created during the method presented.

[0031] Figure 15 is used Figure 13 A description of the final golf club shaft product created by the method described.

[0032] Figure 16 is a process flow chart illustrating the fifth method of the present invention.

[0033] Figure 17A 、 17B and 17C is used Figure 16 The method presented herein is a description of a golf club shaft precursor and final product created.

[0034] Figure 18 is a process flow chart illustrating the sixth method of the present invention.

[0035] Figure 19A and 19B is Figure 18 A description of a golf club shaft precursor created during the method presented.

[0036] Figure 20 is used Figure 18 A description of the final golf club shaft product created by the method described.

[0037] Figure 21 is a process flow chart illustrating the seventh method of the present invention.

[0038] Figure 22A and 22B is Figure 21 A description of a golf club shaft precursor created during the method presented.

[0039] Figure 23 is used Figure 21 A description of the final golf club shaft product created by the method described.

[0040] Figure 24 is a process flow chart illustrating the eighth method of the present invention.

[0041] Figure 25 is Figure 24 A description of a golf club shaft precursor created during the method presented.

[0042] Figure 26 is used Figure 24A description of the final golf club shaft product created by the method described. DETAILED DESCRIPTION

[0043] The present invention relates to a composite curved tip golf club shaft 10 having improved performance characteristics, and methods of making such a golf club shaft. The curved tip shaft disclosed herein allows for a clean and face-balanced golf club head design, particularly for putters.

[0044] Figures 1 to 2 The curved tip golf club shaft 10 of the present invention is shown in FIG. The shaft 10 includes a butt section 20, a tapered middle section 30, and a tip section 40 having a single bend 42 with a bend angle A1 of 10 to 30 degrees. Figure 3 、 4A In the second embodiment shown in Figures 4 and 4B, the shaft 10 has the same characteristics as the preferred embodiment, except that the tip section 40 has two bends 44, 46, each having a bend angle A2, A3 ranging from 10 degrees to 30 degrees, although A2 is preferably between 20 degrees and 25 degrees, and A3 is preferably between 12 degrees and 16 degrees.

[0045] In each of these embodiments, the outer diameter D1 of the butt section 20 of the shaft 10 ranges from about 0.550 inches to about 0.625 inches, preferably from about 0.560 inches to about 0.615 inches, and most preferably from about 0.600 inches to about 0.610 inches. However, in alternative embodiments, the butt section 20 is tapered and decreases in outer diameter by less than about 0.010 inches per linear inch along the longitudinal axis 15 of the shaft. In each of these embodiments, the outer diameter D2 of the intermediate section 30 ranges from 0.300 inches to 0.600 inches, and the outer diameter D3 of the tip section 40 preferably ranges from 0.350 inches to 0.360 inches.

[0046] In each embodiment, the length L1 of the docking section 20 typically ranges from about 4 inches to about 16 inches, and preferably from about 8 inches to about 14 inches, depending on the desired shaft stiffness. The shaft 10 preferably has an overall length L2 of less than 40 inches, a mass of less than 100 grams, a torque of less than 1.5 degrees, and a frequency greater than 360 cycles per minute (cpm). When assembled into a complete golf club, and particularly a putter, the shaft 10 is paired with a grip having a mass ranging from 40 grams to 65 grams and a putter head having a mass ranging from 300 grams to 400 grams.

[0047] A first method 100 of manufacturing the curved tip composite golf club shaft 10 of the present invention is as follows: Figure 5. In a first step 102, the prepreg composite sheet is cut into shape, and in a second step 104 (which may occur simultaneously with the first step 102), a rigid tube 12, which may be made of a metal (e.g., aluminum, steel, titanium, etc.) or a polymer (e.g., plastic, composite), is bent or fabricated to have the desired shape. In a third step 106, the bent tube 12 is wrapped with multiple layers of prepreg sheet to form a first precursor shaft, and in a fourth step 108, an adhesive tape is wrapped around the first precursor shaft to provide pressure during curing. In a fifth step 110 (optional), a tubular composite may also be wrapped around the first precursor shaft. In a sixth step 112, the precursor shaft is cured to form a second precursor shaft, and in a seventh, final step 114, the second precursor shaft has the appearance features applied to form the finished shaft 10, which is Figure 6 The finished shaft 10 includes the bent tube 12 from the second step 104 , and the prepreg sheet 14 and / or tubular composite 16 .

[0048] A second preferred method 120 of manufacturing the curved tip composite golf club shaft 10 of the present invention is Figure 7 . In a first step 122, a rigid tube 12, which may be made of a metal (e.g., steel, aluminum alloy, titanium, etc.) or a polymer (e.g., plastic, composite, etc.), is bent or otherwise fabricated into a desired shape. In a second step 124, a removable mandrel 50 is inserted into the bent tube 12. In a third step 126, the prepreg sheet 14 is cut into the desired shape. In a fourth step 128, the prepreg sheet 14 is wrapped around the bent tube 12 to form a first precursor shaft. In a fifth step 130, an adhesive tape is wrapped around the first precursor shaft to provide pressure during curing, and in a sixth, optional step 132, a tubular composite 16 may also be wrapped around the first precursor shaft. In a seventh step 134, the first precursor shaft is cured to form a second precursor shaft 18, Figure 8 In an eighth step 136, the tapered tip 55 of the mandrel 50 is removed from the curved tube 12, and in a ninth step 138, the second precursor shaft 18 is trimmed by applying cosmetic features to create a hollow final shaft 10, such as Figure 9 As shown in .

[0049] A third method 140 of manufacturing the hollow curved tip composite golf club shaft 10 of the present invention is as follows: Figure 10 In a first step 142, the prepreg sheet 14 is cut into a desired shape. In a second step 144, the prepreg sheet 14 and / or the tubular braided composite 16 is wrapped around the flexible core 17 to form a first precursor, and in a third step 146, the first precursor is rolled to form a straight second precursor shaft 18, as shown. Figure 11AIn a fourth step 148, adhesive tape is wrapped around the second precursor shaft 18 to provide pressure during curing, and in a fifth step 150, the resulting combined portion is cured to form the third precursor shaft 19. In a sixth step 152, the tip 19a of the third precursor shaft 19 is placed in the forming mold 58 while still at a temperature above the glass transition temperature Tg, as shown. Figure 11B In a seventh step 154, the resulting structure is subjected to final curing, in an eighth step 156, the flexible core 17 is removed from the structure, and in a ninth final step 158, the structure is cosmetically trimmed to produce Figure 12 The final hollow golf club shaft 10 is shown in FIG.

[0050] A fourth method 160 of manufacturing the curved tip composite golf club shaft 10 of the present invention is as follows: Figure 13 In a first step 162, the prepreg sheet 14 is cut into the desired shape. In a second step 164, the prepreg sheet 14 and / or the tubular braided composite 16 is wrapped around the flexible core 17, which is joined to the rod 52 made of a rigid material (e.g., metal) to form a first precursor, and in a third step 166, the first precursor is rolled to form a straight second precursor shaft 18, as shown. Figure 14A In a fourth step 168, adhesive tape is wrapped around the second precursor shaft 18 to provide pressure during curing, and in a fifth step 170, the resulting combination is cured to form the third precursor shaft 19. In a sixth step 172, the tip 19a of the third precursor shaft 19 is placed in the forming mold 58 while still at a temperature above Tg, as shown. Figure 14B The flexible core 17 is bendable, while the metal rod 52 is not bendable. In a seventh step 174, the resulting structure is subjected to final curing, in an eighth step 176, the flexible core 17 and the rod 52 are removed from the structure, and in a ninth step 178, the structure is cosmetically trimmed to form Figure 15 The final golf club shaft 10 is shown in FIG.

[0051] A fifth method 180 of manufacturing the curved tip composite golf club shaft 10 of the present invention is as follows: Figure 16 In a first step 182, the prepreg sheet 14 is cut into the desired shape. In a second step 184, the prepreg sheet 14 and / or the tubular braided composite 16 is wrapped around a flexible core 17, which may be made of foam, to form a first precursor, and in a third step 186, the first precursor is rolled to form a straight second precursor shaft 18, as shown. Figure 17AIn a fourth step 188, adhesive tape is wrapped around the second precursor shaft 18 to provide pressure during curing, and in a fifth step 190, the resulting combined portion is cured to form the third precursor shaft 19. In a sixth step 192, the tip 19a of the third precursor shaft 19 is placed in the forming mold 58 while still at a temperature above Tg, as shown. Figure 17B In a seventh step 194, the resulting structure is subjected to final curing, in an eighth step 196, the inner diameter of the tip 19a is drilled or reamed to form a recess 19b in the tip 19a shaped to receive the short, thick shank, and in a ninth final step 198, the structure is cosmetically trimmed to form Figure 17C The final golf club shaft 10 is shown in FIG. In this embodiment, the core 17 remains in the shaft 10.

[0052] A sixth method 200 of manufacturing the curved tip composite golf club shaft 10 of the present invention is described in detail. Figure 18 . In a first step 202, a cylinder 201 made of a rigid material (such as metal or plastic) is mounted on the tip of a core 203, which may be a permanent flexible core or foam. In a second step 204, which may occur simultaneously with the first step 202, the prepreg sheet 14 is cut into the desired shape. In a third step 206, the prepreg sheet 14 and / or the tubular braided composite 16 is wrapped around the core 203 to form a first precursor, and in a fourth step 208, the first precursor is rolled to form a straight second precursor shaft 18, as shown. Figure 19A In a fifth step 210, adhesive tape is wrapped around the second precursor shaft 18 to provide pressure during curing, and in a sixth step 212, the resulting combination is fully cured to form the third precursor shaft 19. In a seventh step 214, at least the tip 19a of the third precursor shaft 19 is reheated and placed in the forming mold 58 while still at a temperature above Tg, as shown. Figure 19B In the eighth step 216, the resulting structure is subjected to final curing, and in the ninth step 218, the structure is cosmetically trimmed to produce Figure 20 The final golf club shaft 10 shown in FIG. Figure 20 As shown in , this golf club shaft 10 includes a pocket 19b (created by the cylinder 201 ) in the tip 19a so it can receive a short, thick shaft while the core 17 remains in the shaft 10 .

[0053] A seventh method 220 of manufacturing the curved tip composite golf club shaft 10 of the present invention is as follows: Figure 21In a first step 222, the prepreg sheet 14 is cut into the desired shape, and in a second step 224, the prepreg sheet 14 and / or the tubular braided composite 16 is wrapped around a tapered rod 52 made of a rigid material (such as plastic or metal), which is engaged with a removable sleeve 211 containing an inflatable airbag 213 to form a first precursor. In a third step 226, the first precursor is rolled to form a straight second precursor shaft 18, as shown. Figure 22A As shown in FIG, and in a fourth step 228, adhesive tape is wrapped around the second precursor shaft 18 to provide pressure during curing.

[0054] At this point, the method 220 branches into two possible paths. According to the first path, in a fifth step 230, the structure is subjected to partial curing, and in a sixth step 232, the sleeve 211 is removed to form the third precursor shaft 19, the tip 19a of which is placed in the forming mold 58 while still at a temperature above Tg, as shown in FIG. Figure 22B , and the airbag 213 is inflated during bending to support the tip 19a during bending. According to the second path, in a seventh step 234, the second precursor shaft 18 is fully cured, and in an eighth step 236, the sleeve 211 is removed to form the third precursor shaft 19, and the tip 19a of the third precursor shaft 19 is placed in the forming mold 58 while still at a temperature above Tg, as shown. Figure 22B , and the balloon 213 is inflated during bending to support the tip 19a during bending.

[0055] The paths converge at a ninth step 238 where the structure undergoes a final curing process. In a tenth step 240, the bladder 213 is deflated and the bladder 213 and tapered rod 52 are removed from the structure, which is then cosmetically trimmed in an eleventh step 242 to produce Figure 23 In an alternative embodiment, this seventh method 220 can be modified by omitting the removable sleeve, and in another alternative embodiment, the method 220 can be modified by replacing the tapered rod 52 with a metal cylinder that remains permanently in the golf club shaft 10.

[0056] The final eighth method 250 of manufacturing the curved tip composite golf club shaft 10 of the present invention is Figure 24 In a first step 252, the prepreg sheets 14 are cut into the desired shape, and in a second step 254, the prepreg sheets 14 and / or the tubular braided composite 16 are wrapped around a solid, dissolvable core 255, which may be made of salt or foam, to form Figure 25In a third step 256, adhesive tape is wrapped around the second precursor shaft 18 to provide pressure during a fourth curing step 258. In a fifth step 260, the core 255 is dissolved with a fluid, and in a sixth step 262, the resulting structure is cosmetically trimmed to form Figure 26 The final hollow golf club shaft 10 is shown in FIG.

[0057] In the context of putter-type golf club heads, lower torque measurements directly correlate to lower putter head twist at impact, also known as torsional robustness, which represents how offline the putter is relative to address. Composite shafts can provide the same or lower twist at impact than steel shafts while being significantly lighter than steel shafts. The lower mass of the shaft resulting from the inventive method disclosed herein allows the putter to balance weight at the grip, creating a more consistent putting stroke. The shaft formed from the inventive method disclosed herein also frees up any weight that could be placed in the putter head, providing a more consistent putting stroke while maintaining the same swing weight and overall weight. The curvature in the composite shaft allows for a low-torque, lightweight putter shaft and can create a face-balanced club with a curved tip. Testing also showed that higher frequencies were statistically significantly correlated with higher ball speeds, more topspin, and a higher launch angle at impact. Because these are desirable results, shafts preferably have a minimum frequency threshold.

[0058] Based on the foregoing, it is believed that those skilled in the relevant art will recognize the significant advancements of the present invention and will readily appreciate that, although the present invention has been described in conjunction with the preferred embodiments thereof and other embodiments illustrated in the accompanying drawings, many equivalent changes, modifications, and substitutions may be made thereto without departing from the spirit and scope of the present invention, which is not limited by the foregoing except as may appear in the claims appended hereto. The section headings contained herein are not intended to be limiting. Accordingly, the embodiments of the present invention in which exclusive property or privilege is claimed are defined in the claims appended hereto.

Claims

1. A method for manufacturing a golf club shaft, comprising the following steps: cutting the composite material into a plurality of composite parts; joining the flexible core to a rod comprised of a rigid material; wrapping the composite member around the flexible core and shaft combination to form a first precursor shaft; rolling the first front body shaft to form a straight second front body shaft; wrapping adhesive tape around the second front body shaft; partially curing the second precursor shaft to form a third precursor shaft having a tip; placing an air bag in the third front shaft and inflating the air bag; placing the tip in a forming mold when the tip is at a temperature above the glass transition temperature Tg; bending the tip within the forming die to form a first curved fourth precursor shaft having a first bend angle of 20 to 25 degrees relative to the non-tip shaft; bending the tip within the forming die to form the fourth front shaft with a second bend having a second bend angle of 12 to 16 degrees relative to the first bend angle; curing the fourth precursor shaft; removing the flexible core and shaft combination from the fourth precursor shaft; and Appearance features are applied to the fourth precursor shaft to create a final golf club shaft.

2. The method of claim 1 , wherein the final golf club shaft has a torque of less than 1.5 degrees and a frequency greater than 360 cycles per minute.

3. The method of claim 1, wherein the rigid material is selected from the group consisting of a metal alloy and a polymer, and wherein the composite material is selected from the group consisting of a prepreg material and a tubular braided composite.

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