Fiber-reinforced sandwich composite board and manufacturing method thereof

Abstract

Fiber reinforced sandwich composite panels and methods of making are described. A fiber reinforced sandwich composite panel includes a top layer, a bottom layer, a core layer, a continuous reinforcing yarn passing through the panel at a plurality of apertures, and a continuous weft yarn interlocked with the reinforcing yarn.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 365,751, filed on June 2, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to fiber reinforced sandwich composite panels. Background Art

[0004] Sandwich composite panels are commonly used in a variety of automotive, marine, robotic, and aerospace applications. These panels are favored due to their high strength and stiffness, as well as lower weight compared to solid materials. The outer layers of the panel provide support for in-plane loads, and the opposing layers act in compression and tension to support the panel. The inner layers provide support for out-of-plane loads and shear loads. In applications where higher strength and higher stiffness are required, reinforcing fibers can be included in the core layer. The inner layers are typically attached to each outer layer using an adhesive layer. However, sandwich composite panels often experience delamination and peeling of the adhesive layer. The reinforcing fibers present in the core layer of the panel do not provide any advantage in preventing delamination because they do not make the inner layer integral to the outer layers. Summary of the invention

[0005] The aspects, features, benefits and advantages of the embodiments described herein will become apparent with reference to the following description, appended claims and accompanying drawings, in which:

[0006] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel, comprising: a sandwich composite panel comprising: a top layer; a bottom layer; a core layer located between the top layer and the bottom layer; and a plurality of holes, wherein each of the plurality of holes passes through each layer of the composite panel; and continuous reinforcing yarn, wherein the reinforcing yarn passes through each of the plurality of holes; wherein the thickness of the fiber-reinforced sandwich composite panel is greater than about 30 mm, and the volume fraction of the continuous reinforcing yarn in each of the plurality of holes is greater than about 50%.

[0007] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel wherein the volume fraction of the continuous reinforcement yarn in each of the plurality of holes is about 55%, about 60%, about 65%, about 70%, or any value or range between any two of these values.

[0008] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel, wherein the thickness of the fiber-reinforced sandwich composite panel is about 35 mm, about 40 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, about 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

[0009] In some embodiments, the technology described herein is directed to a fiber-reinforced sandwich composite panel wherein the thickness of the top layer is about 0.1 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 18 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0010] In some embodiments, the technology described herein relates to fiber reinforced sandwich composite panels, wherein the top layer includes polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, fiberglass, polyurethane, polyvinyl chloride, PET, polyethylene, nylon, or combinations thereof.

[0011] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel, wherein the thickness of the bottom layer is about 0.1 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 18 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0012] In some embodiments, the technology described herein relates to fiber reinforced sandwich composite panels, wherein the bottom layer includes polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, fiberglass, polyurethane, polyvinyl chloride, PET, polyethylene, nylon, or combinations thereof.

[0013] In some embodiments, the technology described herein is directed to a fiber reinforced sandwich composite panel wherein the core layer has a thickness of about 25 mm, about 30 mm, about 35 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

[0014] In some embodiments, the technology described herein relates to fiber reinforced sandwich composite panels wherein the core layer comprises polystyrene, polyurethane, extruded polystyrene, polyisocyanurate, mineral wool, aluminum, polyvinyl chloride, fiberglass, polycarbonate, PET, polyethylene, carbon fiber, wood, or combinations thereof.

[0015] In some embodiments, the technology described herein relates to a fiber reinforced sandwich composite panel, wherein the core layer has a structure, wherein the structure comprises a foam, a honeycomb, a grid, a composite tube, or a combination thereof.

[0016] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel, wherein the diameter of each of the plurality of holes is about 5 mm, about 4 mm, about 3 mm, about 2 mm, about 1 mm, about 0.9 mm, about 0.8 mm, about 0.7 mm, about 0.6 mm, about 0.5 mm, or any value or range between any two of these values.

[0017] In some embodiments, the technology described herein relates to a fiber reinforced sandwich composite panel wherein a plurality of holes are positioned in a periodic arrangement.

[0018] In some embodiments, the technology described herein relates to a fiber reinforced sandwich composite panel wherein a plurality of holes are positioned in a dispersed arrangement.

[0019] In some embodiments, the technology described herein relates to a fiber reinforced sandwich composite panel, wherein the fiber reinforced sandwich composite panel comprises a density of pores, wherein the density of pores is 0.1 pores / cm 2, 0.2 holes / cm 2 , 0.3 holes / cm 2 , 0.4 holes / cm 2 , 0.5 holes / cm 2 , 0.6 holes / cm 2 , 0.7 holes / cm 2 , 0.8 holes / cm 2 , 0.9 holes / cm 2 , 1 hole / cm 2 , 2 holes / cm 2 , 3 holes / cm 2 , 4 holes / cm 2 , 5 holes / cm 2 , or any value or range between any two.

[0020] In some embodiments, the technology described herein relates to fiber-reinforced sandwich composite panels, wherein the continuous reinforcement yarns include carbon fibers, glass fibers, aramid fibers, aramid fibers, polyester fibers, natural fibers, ultra-high molecular weight polyethylene fibers, or combinations thereof.

[0021] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel, wherein the continuous reinforcing fiber has a tow value, wherein the tow value of the continuous reinforcing yarn is about 1K, about 2K, about 3K, about 4K, about 5K, about 6K, about 8K, about 10K, about 12K, about 15K, about 18K, about 21K, about 24K, about 28K, about 30K, about 32K, about 36K, about 40K, about 44K, about 48K, about 50K, or any value or range between any two of these values.

[0022] In some embodiments, the technology described herein relates to fiber-reinforced sandwich composite panels wherein the continuous reinforcement yarn comprises a plurality of stitches.

[0023] In some embodiments, the technology described herein relates to a fiber-reinforced sandwich composite panel further comprising continuous weft yarns.

[0024] In some embodiments, the technology described herein is directed to fiber reinforced sandwich composite panels wherein a continuous weft yarn is interlocked with a continuous reinforcement yarn at each of a plurality of stitches.

[0025] In some embodiments, the technology described herein relates to fiber-reinforced sandwich composite panels, wherein the continuous weft yarns include carbon fibers, glass fibers, aramid fibers, aramid fibers, ultra-high molecular weight polyethylene fibers, or combinations thereof.

[0026] In some embodiments, the technology described herein relates to a fiber reinforced sandwich composite panel further comprising a resin, wherein the resin is configured to transfer forces to the continuous reinforcement yarns.

[0027] In some embodiments, the technology described herein relates to fiber reinforced sandwich composite panels where the resin comprises a thermoset material.

[0028] In some embodiments, the technology described herein relates to fiber reinforced sandwich composite panels where the resin comprises a thermoplastic.

[0029] In some embodiments, the technology described herein relates to fiber reinforced sandwich composite panels, wherein the resin includes polyester, epoxy, vinyl ester, phenolic, polyurethane, ABS, polyethylene, polystyrene, polycarbonate, acrylic-based resins, or combinations thereof.

[0030] In some embodiments, the technology described herein relates to a method for manufacturing a fiber-reinforced sandwich composite panel, comprising: providing a composite panel having a thickness greater than about 30 mm, comprising: a top layer; a bottom layer; a core layer located between the top layer and the bottom layer; and a plurality of holes, wherein each of the plurality of holes passes through the core layer; providing a continuous reinforcing yarn; providing a continuous weft yarn; forming a stitch at each of the plurality of holes by passing the continuous reinforcing yarn through the top layer, one of the plurality of holes, and the bottom layer; and interlocking the continuous weft yarn with the continuous reinforcing yarn at each stitch.

[0031] In some embodiments, the technology described herein is directed to a method in which each of a plurality of holes passes through a top layer and a bottom layer.

[0032] In some embodiments, the technology described herein is directed to a method wherein the generation of each stitch includes generating the stitch at one of a plurality of holes adjacent to a previous stitch.

[0033] In some embodiments, the technology described herein is directed to a method further comprising providing a resin and infusing the resin into a fiber reinforced sandwich composite panel.

[0034] In some embodiments, the technology described herein is directed to a method further comprising infusing the resin by one of vacuum infusion, resin transfer molding, reaction injection molding, vacuum assisted resin transfer molding, resin film infusion, or prepreg techniques.

[0035] In some embodiments, the technology described herein is directed to a method further comprising degassing the resin.

[0036] In some embodiments, the technology described herein relates to a method further comprising curing the fiber reinforced sandwich composite panel.

[0037] In some embodiments, the technology described herein relates to a method wherein a fiber reinforced sandwich composite panel is cured at a temperature of about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, or any value or range between any two of these values. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The aspects, features, benefits and advantages of the embodiments described herein will become apparent with reference to the following description, appended claims and accompanying drawings, in which:

[0039] Figure 1 A cross-sectional view of a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0040] Figure 2 A cross-sectional view of a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0041] Figure 3 A cross-sectional view of a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0042] Figure 4 A schematic diagram showing a top surface of a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0043] Figure 5 A flow chart of a method for manufacturing a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0044] FIG. 6A to FIG. 6D A schematic diagram of a method for manufacturing a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0045] FIG. 7A to FIG. 7C A reconstruction diagram of a fiber reinforced sandwich composite panel according to an embodiment of the present disclosure is shown.

[0046] Figure 8 Graph showing representative results of flat compression testing of fiber reinforced sandwich composite panels according to embodiments of the present disclosure.

[0047] Fig. 9 A schematic diagram showing the surface of a fiber reinforced composite panel during a flat compression test according to an embodiment of the present disclosure.

[0048] Fig.10 Graph showing representative results of edgewise compression testing of fiber reinforced sandwich composite panels according to embodiments of the present disclosure.

[0049] Fig.11 A schematic diagram showing a surface of a fiber reinforced composite panel before edgewise compression testing according to an embodiment of the present disclosure is shown.

[0050] Fig.12 A schematic diagram showing the surface of a fiber reinforced composite panel during edgewise compression testing according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0051] Embodiments relate to a fiber reinforced sandwich composite panel, comprising a top layer, a bottom layer, a core layer between the top layer and the bottom layer, a plurality of holes passing through each layer, a continuous reinforcing yarn, and a continuous weft yarn. The continuous reinforcing yarn passes through each of the plurality of holes and is present in each hole at a volume fraction greater than 50 wt.%. The continuous reinforcing yarn and the continuous weft yarn significantly improve the delamination resistance of the panel while increasing the out-of-plane stiffness and out-of-plane strength. The thickness of the fiber reinforced sandwich composite panel greater than about 30 mm also increases the out-of-plane stiffness and out-of-plane strength without a significant increase in weight.

[0052] Figure 1 A cross-sectional view of a fiber reinforced sandwich composite panel 100 according to an embodiment of the present disclosure is shown. The fiber reinforced sandwich composite panel 100 may include a top layer 101, a bottom layer 102, and a core layer 103 located between the top layer 101 and the bottom layer 102. The fiber reinforced sandwich composite panel 100 may further include a plurality of holes 105 that pass through each of the top layer 101, the bottom layer 102, and the core layer 103 at an angle perpendicular to the top layer 101. The fiber reinforced sandwich composite panel 100 includes a continuous reinforcing yarn 104, wherein the continuous reinforcing yarn 104 may be configured to pass through each of the plurality of holes 105. The continuous reinforcing yarn 104 may be configured to provide a plurality of stitches 106, wherein each of the plurality of stitches 106 is located at the bottom of each of the plurality of holes 105.

[0053] The thickness of the fiber reinforced sandwich composite panel 100 is greater than about 30 mm. The thickness of the fiber reinforced sandwich composite panel 100 may be about 35 mm, about 40 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, about 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

[0054] The top layer 101 is configured to provide support against in-plane forces and lateral bending forces. The top layer 101 may include any material known to those of ordinary skill in the art to be effective in providing support against in-plane forces and lateral bending forces. In some embodiments, the top layer 101 may include one or more of polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, fiberglass, polyurethane, polyvinyl chloride, PET, polyethylene, nylon, or a combination thereof.

[0055] In some embodiments, the top layer 101 may include a woven fabric. Each strand of the woven fabric may have a width of about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value or range between any two of these values. In some embodiments, the tow value of the woven fabric may be about 1K, about 2K, about 3K, about 4K, about 5K, about 6K, about 8K, about 10K, about 12K, about 15K, about 18K, about 21K, about 24K, about 28K, about 30K, about 32K, about 36K, about 40K, about 44K, about 48K, about 50K, or any value or range between any two of these values.

[0056] The thickness of the top layer 101 can be about 0.1 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 18 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0057] The bottom layer 102 is configured to provide support against in-plane forces and lateral bending forces. The bottom layer 102 may include any material known to those of ordinary skill in the art that is effective in providing support against in-plane forces and lateral bending forces. In some embodiments, the bottom layer 102 may include one or more of polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, fiberglass, polyurethane, polyvinyl chloride, PET, polyethylene, nylon, or a combination thereof.

[0058] In some embodiments, the bottom layer 102 may include a woven fabric. Each strand of the woven fabric may have a width of about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value or range between any two of these values. In some embodiments, the tow value of the woven fabric may be about 1K, about 2K, about 3K, about 4K, about 5K, about 6K, about 8K, about 10K, about 12K, about 15K, about 18K, about 21K, about 24K, about 28K, about 30K, about 32K, about 36K, about 40K, about 44K, about 48K, about 50K, or any value or range between any two of these values.

[0059] The thickness of the bottom layer 102 can be about 0.1 mm, about 0.2 mm, 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0060] The core layer 103 is configured to provide support against out-of-plane forces, including out-of-plane shear forces. In some embodiments, the core layer 103 may include one or more of polystyrene, polyurethane, extruded polystyrene, polyisocyanurate, mineral wool, aluminum, polyvinyl chloride, fiberglass, polycarbonate, PET, polyethylene, carbon fiber, wood, or a combination thereof. The thickness of the core layer 103 can be about 25 mm, about 30 mm, about 35 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

[0061] The structure of the core layer 103 can be controlled to control various properties of the fiber reinforced sandwich composite panel 100. The structure of the core layer 103 can include any core structure known to those of ordinary skill in the art. In some embodiments, the structure of the core layer 103 can include foam, honeycomb, grid, composite tube, or a combination thereof. In some embodiments, the grid pattern can be any grid pattern known to those of ordinary skill in the art.

[0062] The continuous reinforcing yarn 104 is configured to provide support for the fiber reinforced sandwich composite plate 100 by improving the out-of-plane stiffness, out-of-plane strength and limiting the peeling between the core layer and the top layer and between the core layer and the bottom layer. The continuous reinforcing yarn 104 may include any material known to those of ordinary skill in the art that effectively provides support against out-of-plane forces. In some embodiments, the continuous reinforcing yarn 104 may include one of carbon fiber, glass fiber, aramid fiber, aramid fiber, polyester fiber, natural fiber, ultra-high molecular weight polyethylene fiber or a combination thereof. In some embodiments, the continuous reinforcing yarn 104 may have a tow value of about 1K, about 2K, about 3K, about 4K, about 5K, about 6K, about 8K, about 10K, about 12K, about 15K, about 18K, about 21K, about 24K, about 28K, about 30K, about 32K, about 36K, about 40K, about 44K, about 48K, about 50K, or any value or range between any two of these values.

[0063] The continuous reinforcing yarn 104 is configured to pass through each of the plurality of holes 105. In some embodiments, the continuous reinforcing yarn 104 is configured to create a plurality of stitches 106, wherein each of the plurality of stitches 106 is located at the bottom of each of the plurality of holes 105. In some embodiments, the volume fraction of the continuous reinforcing yarn 104 in each of the plurality of holes 105 is greater than about 50%. The volume fraction of the continuous reinforcing yarn 104 in each of the plurality of holes 105 may be about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, or any value or range between any two of these values.

[0064] In some embodiments, the plurality of holes 105 passes through each layer of the fiber reinforced sandwich composite panel 100. In some embodiments, each of the plurality of holes 105 has a diameter of about 5 mm, about 4 mm, about 3 mm, about 2 mm, about 1 mm, about 0.9 mm, about 0.8 mm, about 0.7 mm, about 0.6 mm, about 0.5 mm, about 0.4 mm, about 0.3 mm, about 0.2 mm, about 0.1 mm, or any value or range between any two of these values.

[0065] In some embodiments, each of the plurality of holes 105 is positioned in a periodic arrangement in the reinforced sandwich composite plate. In some embodiments, each of the plurality of holes 105 is positioned in a dispersed arrangement in the reinforced sandwich composite plate. The distance between any two of the plurality of holes 105 can be about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, about 15 mm, about 16 mm, about 17 mm, about 18 mm, about 19 mm, about 20 mm, 21 mm, about 22 mm, about 23 mm, about 24 mm, about 25 mm, about 26 mm, about 27 mm, about 28 mm, about 29 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0066] The fiber reinforced sandwich composite panel 100 may generally include a plurality of holes 105 of any density. For example, the density of the plurality of holes 105 may be 0.1 holes / cm 2 , 0.2 holes / cm 2 , 0.3 holes / cm 2 , 0.4 holes / cm 2 , 0.5 holes / cm 2 , 0.6 holes / cm 2 , 0.7 holes / cm 2 , 0.8 holes / cm 2 , 0.9 holes / cm 2 , 1 hole / cm 2 , 2 holes / cm 2 , 3 holes / cm 2 , 4 holes / cm 2 , 5 holes / cm 2 , or any value or range between any two of these values.

[0067] In some embodiments, each of the plurality of holes 105 is configured at the same angle relative to the top layer. In some embodiments, each of the plurality of holes 105 is perpendicular to the top layer. The angle of the plurality of holes 105 relative to the top layer 101 can be about 5°, about 10°, about 15°, about 20°, about 25°, about 30°, about 35°, about 40°, about 45°, about 50°, about 55°, about 60°, about 65°, about 70°, about 75°, about 80°, about 85°, or any value or range between any two of these values.

[0068] Figure 2 FIG. 2 shows a cross-sectional view of a fiber reinforced sandwich composite panel 200 according to an embodiment of the present disclosure. The fiber reinforced sandwich composite panel 200 is similar to Figure 1The fiber reinforced sandwich composite panel 200 may include a top layer 201, a bottom layer 202, and a core layer 203 located between the top layer 201 and the bottom layer 202. The fiber reinforced sandwich composite panel 200 may also include a plurality of holes 205 configured at an angle perpendicular to the top layer 201. The fiber reinforced sandwich composite panel 200 may include a continuous reinforcing yarn 204, a plurality of stitches 207, and a continuous weft yarn 206, the continuous weft yarn 206 being configured to interlock with the continuous reinforcing yarn 204 at the plurality of stitches 207.

[0069] The continuous weft yarn 206 is configured to interlock with the continuous reinforcement yarn 204. In some embodiments, the continuous weft yarn 206 is configured to interlock with the continuous reinforcement yarn 204 at each of the plurality of stitches 207. The continuous weft yarn 206 may include any material known to one of ordinary skill in the art. In some embodiments, the continuous weft yarn 206 may include one of carbon fiber, glass fiber, aramid fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, or a combination thereof.

[0070] The continuous reinforcement yarns 204 and continuous weft yarns 206 are configured in combination to integrate the top layer 201 with the core layer 203 and to integrate the bottom layer 202 with the core layer 203. The integration of the top layer 201 with the core layer 203 and the bottom layer 202 with the core layer 203 provides significant improvements in preventing delamination of the fiber reinforced sandwich composite panel 200.

[0071] Figure 3 FIG. 3 is a cross-sectional view of a fiber reinforced sandwich composite panel 300 according to an embodiment of the present disclosure. The fiber reinforced sandwich composite panel 300 is similar to Figure 1 The fiber reinforced sandwich composite panel 300 may include a top layer 301, a bottom layer 302, and a core layer 303 located between the top layer 301 and the bottom layer 302. The fiber reinforced sandwich composite panel 300 may further include a plurality of holes 305 configured at an angle that is not perpendicular to the top layer 301. The fiber reinforced sandwich composite panel 300 may include a continuous reinforcing yarn 304, a plurality of stitches 307, and a continuous weft yarn 306, the continuous weft yarn 306 being configured to interlock with the continuous reinforcing yarn 304 at the plurality of stitches 307.

[0072] In some embodiments, each of the plurality of holes 305 is configured at the same angle relative to the top layer. The angles of the plurality of holes 305 control the angle at which the continuous reinforcing yarn 304 passes through the fiber-reinforced sandwich composite panel 300. The angles of the plurality of holes 305 can be used to control the mechanical properties of the fiber-reinforced sandwich composite panel 300 in different directions, including strength and stiffness. The angles of the plurality of holes 305 relative to the top layer 301 can be about 5°, about 10°, about 15°, about 20°, about 25°, about 30°, about 35°, about 40°, about 45°, about 50°, about 55°, about 60°, about 65°, about 70°, about 75°, about 80°, about 85°, or any value or range between any two of these values.

[0073] Figure 4 A schematic diagram of the top surface of a fiber reinforced sandwich composite panel 400 according to an embodiment of the present disclosure is shown. The fiber reinforced sandwich composite panel 400 includes a top layer 401, a continuous reinforcing yarn 402, and a plurality of holes 403. The continuous reinforcing yarn 402 passes through each hole 403 and is arranged along the top layer 401 between each of the plurality of holes 403. This provides integration between the top layer 401 and the core layer of the fiber reinforced sandwich composite panel 400.

[0074] The thickness of the fiber reinforced sandwich composite panel 400 is greater than about 30 mm. The thickness of the fiber reinforced sandwich composite panel 400 may be about 35 mm, about 40 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, about 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

[0075] The top layer 401 is configured to provide support against in-plane forces and lateral bending forces. The top layer 401 may include any material known to those of ordinary skill in the art that is effective in providing support against in-plane forces and lateral bending forces. In some embodiments, the top layer 401 may include one or more of polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, fiberglass, polyurethane, polyvinyl chloride, PET, polyethylene, nylon, or a combination thereof.

[0076] In some embodiments, the top layer 401 may include a woven fabric. The width of each woven fabric may be about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value or range between any two of these values. In some embodiments, the tow value of the woven fabric may be about 1 K, about 2 K, about 3 K, about 4 K, about 5 K, about 6 K, about 8 K, about 10 K, about 12 K, about 15 K, about 18 K, about 21 K, about 24 K, about 28 K, about 30 K, about 32 K, about 36 K, about 40 K, about 44 K, about 48 K, about 50 K, or any value or range between any two of these values.

[0077] The thickness of the top layer 401 can be about 0.1 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 18 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0078] The continuous reinforcing yarn 402 is configured to provide support for the fiber reinforced sandwich composite panel 400 by improving out-of-plane stiffness, out-of-plane strength, and limiting debonding between the core layer and the top layer and between the core layer and the bottom layer. The continuous reinforcing yarn 402 may include any material known to those of ordinary skill in the art that effectively provides support against out-of-plane forces. In some embodiments, the continuous reinforcing yarn 402 may include one of carbon fiber, glass fiber, aramid fiber, aramid fiber, polyester fiber, natural fiber, ultra-high molecular weight polyethylene fiber, or a combination thereof.

[0079] The continuous reinforcing yarn 402 is configured to pass through each of the plurality of holes 403. The continuous reinforcing yarn 402 is configured to pass through adjacent holes 403 in a continuous order. The volume fraction of the continuous reinforcing yarn 402 in each of the plurality of holes 403 is greater than about 50%. The volume fraction of the continuous reinforcing yarn 402 in each of the plurality of holes 403 may be about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, or any value or range between any two of these values.

[0080] A plurality of holes 403 passes through each layer of the fiber reinforced sandwich composite panel 400. In some embodiments, the diameter of each of the plurality of holes 403 is about 5 mm, about 4 mm, about 3 mm, about 2 mm, about 1 mm, about 0.9 mm, about 0.8 mm, about 0.7 mm, about 0.6 mm, about 0.5 mm, about 0.4 mm, about 0.3 mm, about 0.2 mm, about 0.1 mm, or any value or range between any two of these values.

[0081] In some embodiments, each of the plurality of holes 403 is positioned in a periodic arrangement in the reinforced sandwich composite plate. In some embodiments, each of the plurality of holes 403 is positioned in a dispersed arrangement in the reinforced sandwich composite plate. The distance between any two of the plurality of holes 403 can be about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, about 15 mm, about 16 mm, about 17 mm, about 18 mm, about 19 mm, about 20 mm, 21 mm, about 22 mm, about 23 mm, about 24 mm, about 25 mm, about 26 mm, about 27 mm, about 28 mm, about 29 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

[0082] The fiber reinforced sandwich composite panel 400 may generally include a plurality of holes 403 of any density. For example, the density of the plurality of holes 403 may be 0.1 holes / cm 2 , 0.2 holes / cm 2 , 0.3 holes / cm 2 , 0.4 holes / cm 2 , 0.5 holes / cm 2 , 0.6 holes / cm 2 , 0.7 holes / cm 2 , 0.8 holes / cm 2 , 0.9 holes / cm 2 , 1 hole / cm 2 , 2 holes / cm 2 , 3 holes / cm 2 , 4 holes / cm 2 , 5 holes / cm 2 , or any value or range between any two of these values.

[0083] In some embodiments, each of the plurality of holes 403 is configured at the same angle relative to the top layer. In some embodiments, each of the plurality of holes 403 is perpendicular to the top layer. The angle of the plurality of holes 403 relative to the top layer 401 can be about 5°, about 10°, about 15°, about 20°, about 25°, about 30°, about 35°, about 40°, about 45°, about 50°, about 55°, about 60°, about 65°, about 70°, about 75°, about 80°, about 85°, or any value or range between any two of these values.

[0084] In some embodiments, the fiber reinforced sandwich composite panel further comprises a resin. In some embodiments, the resin is injected into the core space of the fiber reinforced sandwich composite panel and the space of the hole of the fiber reinforced sandwich composite panel. In some embodiments, the resin is configured to transfer force to the continuous reinforcing yarn. In some embodiments, the resin is further configured to bind the continuous reinforcing yarn in place and protect the continuous reinforcing yarn from environmental damage.

[0085] The resin may include any material known to those of ordinary skill in the art that effectively transmits force. In some embodiments, the resin may include a thermosetting material. In some embodiments, the resin may include a thermoplastic. In some embodiments, the resin may include a polyester, epoxy resin, vinyl ester, phenolic resin, polyurethane, ABS, polyethylene, polystyrene, polycarbonate, acrylic resin, or a combination thereof.

[0086] Embodiments are directed to a method of making a fiber reinforced sandwich composite panel comprising a top layer, a bottom layer, a core layer between the top layer and the bottom layer, and a continuous reinforcing yarn.

[0087] Figure 5 A flow chart of a method for manufacturing a fiber-reinforced sandwich composite panel according to an embodiment of the present disclosure is shown. The method includes the following steps: 501, providing a sandwich composite panel having a plurality of holes, a continuous reinforcing yarn and a continuous weft yarn, 502, forming a stitch by passing the reinforcing yarn through one of the plurality of holes, and 503, interlocking the continuous weft yarn with the reinforcing yarn at the stitch. The method includes a checking step 504, wherein if the continuous reinforcing yarn has not passed through each of the plurality of holes, 505, a stitch is formed by passing the reinforcing yarn through the next hole of the plurality of holes. 503, the continuous weft yarn is interlocked with the stitch, and 504, checking is repeated. If the continuous reinforcing yarn has passed through each of the plurality of holes, 506, a fiber-reinforced sandwich composite panel is produced.

[0088] 501, providing a sandwich composite panel having a thickness greater than about 30 mm and having a plurality of holes, a continuous reinforcing yarn, and a continuous weft yarn. In some embodiments, the sandwich composite panel may include a top layer, a bottom layer, and a core layer between the top layer and the bottom layer, and a plurality of holes pass through each layer. In some embodiments, the fiber-reinforced sandwich composite panel may include a top layer, a bottom layer, and a core layer between the top layer and the bottom layer, and a plurality of holes pass through the core layer.

[0089] Then, 502, a stitch is formed by passing the continuous reinforcing yarn through one of the plurality of holes. In some embodiments, the continuous reinforcing yarn passes through the fiber reinforced sandwich composite panel starting from the top layer and passing through the bottom layer. In some embodiments, a threading device is used to pass the continuous reinforcing yarn through the fiber reinforced sandwich composite panel.

[0090] 503, the continuous weft yarn is interlocked with the continuous reinforcing yarn at the stitch. In some embodiments, 503, the continuous weft yarn is interlocked with the continuous reinforcing yarn by passing the continuous weft yarn through the loop in the stitch.

[0091] 504, then a check is performed, wherein if the continuous reinforcement yarn has not passed through each of the plurality of holes, 505, a stitch is formed at a next of the plurality of holes using the continuous reinforcement yarn, wherein the next of the plurality of holes is adjacent to the previous stitch. 503, the continuous weft yarn is interlocked with the continuous reinforcement yarn until the continuous reinforcement yarn passes through each of the plurality of holes, and the check 504 is repeated. 506, if the continuous reinforcement yarn has passed through each of the plurality of holes, a fiber reinforced sandwich composite panel is produced.

[0092] In some embodiments, a resin is provided and injected into the fiber reinforced sandwich composite panel. In some embodiments, the resin is injected into the fiber reinforced sandwich composite panel in the spaces between the core layer and the plurality of holes. The resin can be injected by any injection method known to those skilled in the art. In some embodiments, the resin is injected by one of vacuum infusion, resin transfer molding, reaction injection molding, vacuum assisted resin transfer molding, resin film injection, or prepreg technology.

[0093] In some embodiments, the method further comprises degassing the resin. In some embodiments, degassing is performed to remove residual air in the resin after resin injection. Air pockets can be high stress areas in the fiber reinforced sandwich composite panel and lead to failure.

[0094] In some embodiments, the method further comprises curing the fiber reinforced sandwich composite panel. Curing can be performed at ambient temperature, a temperature of about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, or any value or range between any two of these values. In some embodiments, curing comprises a first curing at a first temperature and a second curing at a second temperature.

[0095] FIG. 6A to FIG. 6D A schematic diagram of a method for manufacturing a fiber reinforced sandwich composite panel according to an embodiment of the present disclosure is shown. The method may include providing a sandwich composite panel 600, the sandwich composite panel 600 including a top layer 601, a bottom layer 602, a core layer 603 located between the top layer 601 and the bottom layer 602, and a plurality of holes 606. The method further includes providing a continuous reinforcing yarn 604, a threading device 605, and a continuous weft yarn 608. The method includes passing the continuous reinforcing yarn 604 through one of the plurality of holes 606 to produce a stitch 607. 609, the continuous weft yarn 608 is interlocked with the continuous reinforcing yarn 604 at the stitch 607, and the thread insertion device 605 is removed from the continuous reinforcing yarn 604.

[0096] The top layer 601 may be provided as a woven fabric. The top layer 601 may be provided as a nonwoven material. The top layer 601 is provided, wherein the top layer 601 comprises a plurality of holes 606. The top layer 601 is provided, wherein the top layer 601 does not comprise a plurality of holes 606.

[0097] The bottom layer 602 can be provided as a woven fabric. The bottom layer 602 can be provided as a nonwoven material. The bottom layer 602 is provided, wherein the bottom layer 602 includes a plurality of holes 606. The bottom layer 602 is provided, wherein the bottom layer 602 does not include a plurality of holes 606.

[0098] A core layer 603 may be provided that includes any core structure known to a person of ordinary skill in the art. In some embodiments, the structure of the core layer 603 may include foam, honeycomb, grid, composite tube, or a combination thereof. A core layer 603 is provided, wherein the core layer 603 includes a plurality of pores 606.

[0099] The continuous reinforcing yarn 604 may be provided as any material that is effective to pass through the plurality of holes 606 and effective to provide support against out-of-plane forces. The continuous reinforcing yarn 604 may be provided as a single fiber or a plurality of fibers.

[0100] The threading device 605 can be any threading device that effectively passes the continuous reinforcement yarn 604 through the plurality of holes 606. In some embodiments, the thread insertion device 605 is configured to pierce the top layer 601 and the bottom layer 602. In some embodiments, the thread insertion device 605 is a needle. In some embodiments, the thread insertion device 605 includes a first end configured to first pass through the plurality of holes 606 and a second end configured to second pass through the plurality of holes 606. In some embodiments, the second end includes a hole configured to attach the thread insertion device 605 to the continuous reinforcement yarn 604. The hole can be configured to move between an open position and a closed position, wherein the hole is moved to the open position, 609, to remove the thread insertion device 605 from the continuous reinforcement yarn 604, and is moved to the closed position to attach the thread insertion device 605 to the continuous reinforcement yarn 604.

[0101] In some embodiments, the plurality of holes 606 pass through the core layer 603. In some embodiments, the plurality of holes 606 pass through each of the top layer 601, the bottom layer 602, and the core layer 603. The plurality of holes 606 can be provided at an angle of about 5°, about 10°, about 15°, about 20°, about 25°, about 30°, about 35°, about 40°, about 45°, about 50°, about 55°, about 60°, about 65°, about 70°, about 75°, about 80°, about 85°, about 90°, or any value or range between any two of these values ​​relative to the top layer 601.

[0102] The method includes attaching a wire insertion device 605 to the continuous reinforcing yarn 604. The continuous reinforcing yarn 604 is then passed through the sandwich composite panel 600. In some embodiments, the wire insertion device 605 is used to pierce the top layer 601 and the bottom layer 602 of the sandwich composite panel 600 so that each of the plurality of holes 606 extends through each layer of the sandwich composite panel 600.

[0103] The wire insertion device 605 is passed completely through the sandwich composite panel 600 to create a stitch 607 with the continuous reinforcement yarn 604. The continuous weft yarn 608 is then interlocked with the continuous reinforcement yarn 604 at the stitch 607, 609, and the wire insertion device is removed from the continuous reinforcement yarn 604. These steps are repeated until the continuous weft yarn 608 is interlocked with the continuous reinforcement yarn 604 at the stitch 607 at each of the plurality of holes 606.

[0104] Example

[0105] Example 1

[0106] By using a thickness of 30 mm and a density of 80 kg / m 3 Three layers of PVC80 foam are laid on each side with a density of 450g / m 2, carbon fiber fabric with a tow value of 12k and 2×2 twill is used to produce carbon fiber reinforced sandwich composite panels. The carbon fiber fabric was provided by Easy composites Ltd., UK, and the PVC foam was provided by Gurit. The PVC foam has holes with a diameter of 2mm and a spacing of 20×20mm. Continuous carbon fiber yarn with a tow value of 12k is stitched through these holes to produce sample FC-Y1. Samples are also made with continuous carbon fiber yarn with a tow size of 24K to produce sample FC-Y2. Sample FC-N is made without the use of carbon fiber yarn. The carbon fiber yarn was provided by Grafil 34-700 Mitsubishi. The resin is then injected into the sample using vacuum assisted resin infusion (VARI) technology. Epoxy Resin Prime TM 27 and Prime TM Slow hardener, both supplied by Gurit, were mixed in a weight ratio of 100:28 to form the resin. The degassing process was carried out for 10 minutes in a 26LDS26-P professional degassing system from Easy composites Co., Ltd. with the help of an EC20 pump from Easy composites Co., Ltd. The injected samples were cured at room temperature for 16 hours and post-cured in a Precision Composites curing oven from Easy composites Co., Ltd. at 65°C for 7 hours.

[0107] X-ray Computed Tomography - Example 1

[0108] The fiber reinforced composite panels prepared in Example 1 were examined using X-ray computed tomography (CT). X-ray CT scanning of samples FC-N, FC-Y1, and FC-Y2 was performed using Phoenix nanotom m-machine. Samples with dimensions of 40 mm × 40 mm × 33 mm were scanned. The parameters included a 4x objective lens of the scanner, a source voltage of 120 kV, a current of 230 μA, and an exposure time of 1 s per radiograph when collecting 2600 radiographs over 360°. These parameters resulted in a voxel size of 25 μm. The scanned images were then used to create a 3D reconstruction of the sample using Avizo software. Fig. 7A shows a 3D reconstruction of a FC-N sample 700, Figure 7B shows a 3D reconstruction of the FC-Y1 sample, Figure 7C 3D reconstructions of FC-Y2 samples are shown. Each 3D reconstruction includes a hole 701, where the hole may include resin 702 and carbon fiber yarn 703. The software is further used to calculate the volume of each material in the hole. The calculations are shown in Table 1:

[0109] sample Carbon fiber volume percentage (%) FC-N 0 FC-Y1 34 FC-Y2 55

[0110] Flat Pressure Test – Example 1

[0111] The fiber reinforced composite panels prepared in Example 1 were tested using a flat compression test. Five samples of each type were prepared and tested according to ASTM C297. The test was performed using an Instron 5982 machine with a load cell capacity of 100 kN and a loading rate of 1 mm / min. The results are shown in Tables 2 and Figure 8 As shown:

[0112] Table 2

[0113]

[0114] During the flat compression test, 3D digital image correlation (DIC) of the sample surface is performed continuously. DIC is performed using two Basler acA2440 cameras with a resolution of 5MP and a XENOPLAN 1.9 / 35-0901 lens. Observation window 40x30mm 2 , the acquisition rate is 2fps. Fig. 9 Compression images of FC-N 901, FC-Y1902, and FC-Y2903 samples after failure due to flat compression testing are shown. The images include the top layer 904, core layer 905, and bottom layer 906 of each sample. The images and compressive strain (e) are used to analyze the sample after flat compression testing. yy ) Calculate the surface strain map for each sample.

[0115] Compression test along edge – Example 1

[0116] The fiber reinforced composite panels prepared in Example 1 were tested using the edgewise compression test. The sample without continuous fiber reinforcement was called EC-N, the sample reinforced with continuous carbon fiber yarn with a tow value of 12k was called EC-Y1, and the sample reinforced with continuous carbon fiber yarn with a tow value of 24K was called EC-Y2. Five samples of each type were prepared and tested according to the ASTM C364 standard. The test was performed using an Instron 5982 machine with a load cell capacity of 100 kN and a loading rate of 0.5 mm / min. The results are shown in Tables 3 and Fig.10 As shown:

[0117] Table 3

[0118] sample Average ultimate load (N) Ultimate strength(MPa) EC-N 5023 236.96±2.29 EC-Y1 6045 286.66±1.62 EC-Y2 5926 281.38±1.58

[0119] 2D DIC was performed on images of the sample surface taken before stitching and after sample fabrication and before edgewise compression testing. DIC was performed using a Photron Nova S16 camera with a Nikon AF-S VR Micro-Nikkor 105mm f / 2.8G IF-ED lens. Fig.11 The surface roughness of the top surface of the sample before the edgewise compression test is shown. The top surface of EC-N 1101 has the lowest average surface roughness, while the top surface of EC-Y11102 and the top surface of EC-Y3 have highly irregular areas. The highly irregular areas in EC-Y11102 and EC-Y21103 appear around the locations of multiple pins 1104.

[0120] 3D DIC is performed continuously on the sample surface during the edgewise compression test. DIC is performed using two Basler acA2440 cameras with a resolution of 5 MP and a XENOPLAN 1.9 / 35-0901 lens. Observation window 110x70 mm 2 , the acquisition rate is 2fps. Fig.12 Compression images of EC-N, EC-Y1 and EC-Y2 samples during edgewise compression testing before and after failure are shown. The images include image 1201 taken just before sample EC-N failure, image 1202 taken just after sample EC-N failure, image 1203 taken just before sample EC-Y1 failure, image 1204 taken just after sample EC-Y1 failure, image 1205 taken just before sample EC-Y2 failure, and image 1206 taken after EC-Y2 failure. Each image includes a carbon fiber fabric layer 1207 and a core layer 1208.

[0121] The surface strain map of the principal strains for each sample is calculated using the image, and the principal strains (e1) are overlaid on the sample image. The images 1202 / 1204 / 1206 taken after failure include markings 1209 locating the sample failure location. In each edgewise compression test, the failure mode resulted in failure across the entire width of the carbon fiber fabric layer that experienced failure. In each EC-Y2 sample, failure occurred at the pin. In the EC-Y1 sample, failure occurred at the pin or between the pins.

[0122] The present disclosure is not limited to the specific embodiments described in this application, which are intended to illustrate various aspects. It will be apparent to those skilled in the art that many modifications and variations may be made without departing from the spirit and scope of the present invention. In addition to the methods and devices listed here, it will be apparent to those skilled in the art that functionally equivalent methods and devices within the scope of the present invention are apparent from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is limited only by the terms of the appended claims and the full scope of the equivalents of these claims. It should be understood that the present disclosure is not limited to specific methods, reagents, compounds, compositions, or biological systems, which may of course vary. It should also be understood that the terms used herein are only for the purpose of describing specific embodiments, and not for limitation.

[0123] It should be understood that the present invention is not limited to the specific process, composition or method described, because they can change. It should also be understood that the terms used in the specification are only for describing specific versions or embodiments, rather than for limiting the scope of the present invention, which is limited only by the appended claims. Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those of ordinary skill in the art are generally understood. Although any methods and materials similar or equivalent to the methods and materials described herein can be used in the practice or testing of embodiments of the present invention, preferred methods, devices and materials are now described. All publications mentioned herein are incorporated herein by reference in their entirety. Nothing herein should be construed as admitting that the present invention has no right to precede such disclosure by virtue of prior invention.

[0124] It must also be noted that, as used herein and in the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a sandwich composite panel" refers to "one or more sandwich composite panels" and equivalents thereof known to those skilled in the art, and so forth.

[0125] As used herein, the term "about" means ± 10% of the numerical value used. Thus, about 50% means within the range of 45%-55%.

[0126] With respect to the use of substantially any plural and / or singular terms herein, those skilled in the art may translate from the plural to the singular and / or from the singular to the plural as appropriate, depending on the context and / or application. For clarity, various singular / plural arrangements may be expressly set forth herein.

[0127] Those skilled in the art will understand that, in general, the terms used herein, especially in the appended claims (e.g., the bodies of the appended claims), are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to", the term "having" should be interpreted as "having at least", the term "comprising" should be interpreted as "including but not limited to", etc.). Although various compositions, methods, and apparatus are described in terms of "comprising" various components or steps (interpreted to mean "including, but not limited to"), these compositions, methods, and apparatus may also "consist essentially of" the various components and steps, and such terms should be interpreted as defining substantially closed groups of members. Those skilled in the art will further understand that if a specific number of a claim recitation is intended to be introduced, such an intent will be explicitly recited in the claim, and if such recitation is absent, no such intent is present.

[0128] For example, to aid understanding, the following appended claims may contain the use of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be interpreted as implying that a claim recitation introduced by the indefinite article "a" or "an" limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and an indefinite article such as "a" or "an" (e.g., "a" and / or "an" should be interpreted as meaning "at least one" or "one or more"); the same applies to the use of definite articles used to introduce claim recitations.

[0129] Furthermore, even if a specific number of an introduced claim recitation is explicitly recited, one skilled in the art will recognize that such recitation should be interpreted as meaning at least the number of recitations (e.g., a simple recitation of "two recitations" without other modifiers means at least two recitations, or two or more recitations). Still further, in those cases where a convention similar to "at least one of A, B, and C, etc." is used, generally, such construction is intended to enable one skilled in the art to understand the convention (e.g., "a system having at least one of A, B, and C" would include, but is not limited to, systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). In those cases where a convention similar to "at least one of A, B, or C, etc." is used, generally, such construction is intended to enable one skilled in the art to understand the convention (e.g., "a system having at least one of A, B, or C" would include, but is not limited to, systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Those skilled in the art will further understand that, whether in the specification, claims or drawings, virtually any disjunctive word and / or phrase indicating two or more optional terms should be understood to include the possibility of one, any or both of the terms. For example, the phrase "A or B" will be understood to include the possibility of "A" or "B" or "A and B".

[0130] In addition, where features or aspects of the disclosure are described in terms of Markush, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[0131] As will be appreciated by those skilled in the art, for any and all purposes, for example, in terms of providing a written description, all ranges disclosed herein also include any and all possible sub-ranges and combinations of sub-ranges thereof. Any listed range can be easily considered to fully describe and can divide the same range into at least equal halves, one-third, one-quarter, one-fifth, one-tenth, etc. As a non-limiting example, each range discussed here can be easily decomposed into a lower third, a middle third, and an upper third, etc. It will also be appreciated by those skilled in the art that all languages ​​such as "at most", "at least", etc. include the numbers listed, and refer to the ranges that can be subsequently decomposed into sub-ranges as described above. Finally, as will be appreciated by those skilled in the art, the range includes each individual member. Therefore, for example, a group with 1-3 units refers to a group with 1, 2 or 3 units. Similarly, a group with 1-5 units refers to a group with 1, 2, 3, 4 or 5 units, etc.

[0132] Various of the above disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various currently unforeseen or unanticipated substitutions, modifications, variations or improvements may subsequently be made by those skilled in the art, each of which is also intended to be encompassed by the disclosed embodiments.

Claims

1. A fiber-reinforced sandwich composite panel, comprising: Sandwich composite panel, comprising: Top floor; bottom layer; a core layer, the core layer being located between the top layer and the bottom layer; and a plurality of holes, wherein each of the plurality of holes passes through each layer of the composite sheet; and a continuous reinforcing yarn, wherein the reinforcing yarn passes through each of the plurality of holes; Wherein, the thickness of the fiber reinforced sandwich composite panel is greater than about 30 mm, and The volume fraction of the continuous reinforcement yarn in each of the plurality of holes is greater than about 50%.

2. The fiber-reinforced sandwich composite panel of claim 1, wherein the volume fraction of the continuous reinforcement yarn in each of the plurality of holes is about 55%, about 60%, about 65%, about 70%, or any value or range between any two of these values.

3. The fiber-reinforced sandwich composite panel according to claim 1, wherein: The fiber reinforced sandwich composite panel has a thickness of about 35 mm, about 40 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, about 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

4. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3, wherein: The thickness of the top layer is about 0.1 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 18 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

5. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 4, wherein: The top layer includes polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, fiberglass, polyurethane, polyvinyl chloride, PET, polyethylene, nylon, or a combination thereof.

6. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3, wherein: The thickness of the bottom layer is about 0.1 mm, about 0.2 mm, about 0.25 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 12 mm, about 14 mm, about 16 mm, about 18 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or any value or range between any two of these values.

7. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 6, wherein: The bottom layer includes polystyrene, polypropylene, carbon fiber, aramid fiber, aluminum, glass fiber, polyurethane, polyvinyl chloride, PET, polyethylene, nylon or a combination thereof.

8. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3, wherein: The thickness of the core layer is about 25 mm, about 30 mm, about 35 mm, about 45 mm, about 50 mm, about 55 mm, about 60 mm, about 65 mm, about 70 mm, about 75 mm, about 80 mm, about 85 mm, 90 mm, about 95 mm, about 100 mm, about 110 mm, about 120 mm, about 130 mm, about 140 mm, about 150 mm, about 160 mm, about 170 mm, about 180 mm, about 190 mm, about 200 mm, about 225 mm, about 250 mm, about 275 mm, about 300 mm, about 325 mm, about 350 mm, about 375 mm, about 400 mm, about 425 mm, about 450 mm, about 475 mm, about 500 mm, or any value or range between any two of these values.

9. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 8, wherein: The core layer includes polystyrene, polyurethane, extruded polystyrene, polyisocyanurate, mineral wool, aluminum, polyvinyl chloride, fiberglass, polycarbonate, PET, polyethylene, carbon fiber, wood, or a combination thereof.

10. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 8 to 9, wherein: The core layer has a structure, wherein the structure includes foam, honeycomb, grid, composite tube or a combination thereof.

11. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3, wherein: The diameter of each of the plurality of holes is about 5 mm, about 4 mm, about 3 mm, about 2 mm, about 1 mm, about 0.9 mm, about 0.8 mm, about 0.7 mm, about 0.6 mm, about 0.5 mm, or any value or range between any two of these values.

12. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 11, wherein: The plurality of holes are positioned in a periodic arrangement.

13. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 11, wherein: The plurality of holes are positioned in a dispersed arrangement.

14. The fiber-reinforced sandwich composite panel according to claim 1, wherein: The fiber reinforced sandwich composite plate includes a hole density, wherein the hole density is 0.1 hole / cm 2 , 0.2 holes / cm 2 , 0.3 holes / cm 2 , 0.4 holes / cm 2 , 0.5 holes / cm 2 , 0.6 holes / cm 2 , 0.7 holes / cm 2 , 0.8 holes / cm 2 , 0.9 holes / cm 2 , 1 hole / cm 2 , 2 holes / cm 2 , 3 holes / cm 2 , 4 holes / cm 2 , 5 holes / cm 2 , or any value or range between any two.

15. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3, wherein: The continuous reinforcing yarn includes carbon fiber, glass fiber, aramid fiber, aromatic polyamide fiber, polyester fiber, natural fiber, ultra-high molecular weight polyethylene fiber or a combination thereof.

16. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 15, wherein: The continuous reinforcing yarn has a tow value, wherein the tow value of the continuous reinforcing yarn is about 1K, about 2K, about 3K, about 4K, about 5K, about 6K, about 8K, about 10K, about 12K, about 15K, about 18K, about 21K, about 24K, about 28K, about 30K, about 32K, about 36K, about 40K, about 44K, about 48K, about 50K, or any value or range between any two of these values.

17. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 15 to 16, wherein: The continuous reinforcement yarn includes a plurality of stitches.

18. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 17, further comprising continuous weft yarns.

19. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 17 to 18, wherein: The continuous weft yarn interlocks with the continuous reinforcement yarn at each of the plurality of stitches.

20. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 17 to 19, wherein: The continuous weft yarn includes carbon fiber, glass fiber, aramid fiber, aromatic polyamide fiber, ultra-high molecular weight polyethylene fiber or a combination thereof.

21. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3, further comprising a resin, wherein: The resin is configured to transfer force to the continuous reinforcement yarn.

22. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 21, wherein: The resin includes a thermosetting material.

23. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 21, wherein: The resin includes a thermoplastic.

24. The fiber-reinforced sandwich composite panel according to any one of claims 1 to 3 or 21, wherein: The resin includes polyester, epoxy, vinyl ester, phenolic, polyurethane, ABS, polyethylene, polystyrene, polycarbonate, acrylic-based resin or a combination thereof.

25. A method for manufacturing a fiber-reinforced sandwich composite panel, comprising: A composite panel having a thickness greater than about 30 mm is provided, comprising: Top floor; bottom layer; a core layer, the core layer being located between the top layer and the bottom layer; and, a plurality of holes, wherein each of the plurality of holes passes through the core layer; Providing continuous reinforcing yarn; Provide continuous weft yarn; forming a stitch at each of the plurality of holes by passing the continuous reinforcing yarn through the top layer, one of the plurality of holes, and the bottom layer; and The continuous weft yarn is interlocked with the continuous reinforcement yarn at each stitch.

26. The method according to claim 25, wherein: Each of the plurality of holes passes through the top layer and the bottom layer.

27. The method according to claim 25, wherein: The forming of each stitch includes forming a stitch at one of the plurality of holes adjacent to a previous stitch.

28. The method of any one of claims 25-27, further comprising providing a resin and infusing the resin into the fiber reinforced sandwich composite panel.

29. The method of claim 28, further comprising infusing the resin by one of vacuum infusion, resin transfer molding, reaction injection molding, vacuum assisted resin transfer molding, resin film infusion, or prepreg techniques.

30. The method of claim 28, further comprising degassing the resin.

31. The method of any one of claims 28-30, further comprising curing the fiber reinforced sandwich composite panel.

32. The method according to claim 31, wherein: The fiber reinforced sandwich composite panel is cured at a temperature of about 20°C, about 25°C, about 30°C, about 35°C, about 40°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, or any value or range between any two of these values.

Images