Comprehensive shielding signal cable and manufacturing method thereof

Abstract

The invention provides a comprehensive shielding signal cable and a manufacturing method thereof.The comprehensive shielding signal cable comprises a cable core and a protective layer wrapping the cable core, and the protective layer sequentially comprises a composite shielding layer and an outer sheath layer from inside to outside; the composite shielding layer comprises an iron-based amorphous nanocrystalline alloy layer, a 3D woven mesh layer and a conductive polymer coating which are sequentially arranged on the outer side of the cable core from inside to outside; through the gradient composite structure of the iron-based amorphous nanocrystalline alloy layer (low-frequency magnetic shielding), the 3D woven mesh layer (medium-frequency electromagnetic shielding) and the conductive polymer coating (high-frequency electric field shielding), the full-band shielding effectiveness is realized for the first time, meanwhile, the return loss is greatly reduced, the electromagnetic transmission performance and reliability of the cable are improved, and the service life of the cable is prolonged. And the structural stability of the cable is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cable, in particular to a comprehensive shielding signal cable and a manufacturing method thereof. BACKGROUND

[0002] With the development of high-frequency communication and precision instruments, electromagnetic interference (EMI) and radio frequency interference (RFI) have become a key problem affecting the quality of signal transmission. The traditional shielding cable mainly adopts a single metal layer (such as copper foil, aluminum foil) or a metal braid structure, which has the following technical bottlenecks: 1. Insufficient frequency coverage: the shielding effectiveness of the copper / aluminum shielding layer is less than 40 dB for low-frequency magnetic field (<1 MHz), and the high-frequency (>1 GHz) is prone to shielding failure due to skin effect; 2. Poor structural stability: the metal layer is prone to cracking under bending conditions, and the 3D braid layer is prone to geometric deformation, which will both cause the shielding continuity to be destroyed; 3. Interface impedance discontinuity: the different shielding layers form wave impedance discontinuity points due to the difference in material properties, causing signal reflection loss. The existing improvement scheme such as adopting double-layer metal composite shielding improves the shielding effect of the middle frequency, but there is still a problem of mismatching of the thermal expansion coefficient between the nanocrystalline alloy and the conductor layer; the conductive polymer coating also improves the flexibility, but the volume resistivity (>10^-3Ω·cm) leads to insufficient high-frequency attenuation. The disclosure of the above background art is only used to assist in understanding the inventive concept and technical solutions of the present application, and it does not necessarily belong to the prior art of the present patent application, nor does it necessarily provide technical teaching; there is no clear evidence that the above application is novel and creative. SUMMARY

[0003] In order to solve the technical problems of insufficient frequency coverage, poor structural stability and interface impedance discontinuity of the cable, the present application provides a comprehensive shielding signal cable and a manufacturing method thereof, which realizes full-band shielding effectiveness by the gradient composite structure of the iron-based amorphous nanocrystalline alloy layer (low-frequency magnetic shielding), the 3D braid layer (middle-frequency electromagnetic shielding) and the conductive polymer coating (high-frequency electric field shielding), and greatly reduces the echo loss, which not only improves the electromagnetic transmission performance and reliability of the cable, but also improves the structural stability of the cable. In order to achieve the above purpose, the technical scheme of the present application is as follows: On the one hand, the present application provides a comprehensive shielding signal cable, comprising: a cable core and a sheath layer wrapped outside the cable core, the sheath layer comprising a composite shielding layer and an outer jacket layer from inside to outside, the composite shielding layer comprising: an iron-based amorphous nanocrystalline alloy layer, a 3D braid layer and a conductive polymer coating arranged from inside to outside outside the cable core. The application provides a comprehensive shielding signal cable and a manufacturing method thereof, and through a gradient composite structure of an iron-based amorphous nanocrystalline alloy layer (low-frequency magnetic shielding), a 3D braided mesh layer (medium-frequency electromagnetic shielding) and a conductive polymer coating layer (high-frequency electric field shielding), full-band shielding effectiveness is first realized, and echo loss is greatly reduced, so that the electromagnetic transmission performance and reliability of the cable are improved, and the structural stability of the cable is improved. As a preferred technical solution, the iron-based amorphous nanocrystalline alloy layer is Fe (70～75) Cu (0.5～1.5) Nb (2～4) Si (12～15) B (8～10) The amorphous nanocrystalline alloy layer is formed by longitudinally wrapping an iron-based amorphous nanocrystalline alloy strip, and the longitudinal wrapping overlap rate is greater than or equal to 30%. As a preferred technical solution, the 3D braided mesh layer is a three-dimensional mesh structure formed by braiding silver-plated copper wires and carbon fibers at a crossing angle of 40-50 degrees, the surface coverage of the 3D braided mesh is greater than or equal to 95%, and the mass ratio of the silver-plated copper wires to the carbon fibers is (5.5-7):(3-4.5). As a preferred technical solution, the conductive polymer coating layer comprises the following components in percentage by mass: Poly (3, 4-ethylenedioxythiophene) 92%-96%; Polystyrene sulfonate 4%-8%; The thickness of the conductive polymer coating layer is 15-25 mu m. As a preferred technical solution, the cable core comprises a plurality of insulated single wires, and the insulated single wire comprises: A conductor twisted by a plurality of silver-plated copper wires, the silver-plated copper wire comprising a copper wire and a silver-plated layer wrapped outside the copper wire, and the thickness of the silver-plated layer is greater than or equal to 2 mu m; An insulating layer wrapped outside the conductor, the thickness of the insulating layer is 0.75-0.85 mm, and the insulating layer is a nano-modified polytetrafluoroethylene composite insulating layer. As a preferred technical solution, the nano-modified polytetrafluoroethylene composite insulating layer comprises polytetrafluoroethylene and 5-10 nm silicon dioxide nanoparticles, and the mass ratio of the silicon dioxide nanoparticles is 1%-5%. As a preferred technical solution, the cable core comprises a plurality of filling ropes, and the filling rope is a PP tear net film filling rope. As a preferred technical solution, the outer sheath layer comprises the following components in percentage by mass: Polyether block amide elastomer base material 78-82%; Multi-walled carbon nanotubes 18-22%; The thickness of the outer sheath layer is greater than 1.5 mm. In another aspect, the application also provides a manufacturing method of the comprehensive shielding signal cable, and the comprehensive shielding signal cable is prepared by the method, and the method comprises the following steps: The plurality of silver-plated copper wires are twisted into a conductor in a concentric manner, and the lay length is ≤ 12 times of the diameter of the conductor; The nanometer modified polytetrafluoroethylene composite material is high-temperature extruded to coat the outside of the conductor, and after cooling, the insulation single wire is formed through irradiation crosslinking; At least two insulation single wires and the filling rope are twisted together to form a cable core; The composite shielding layer and the outer sheath layer are sequentially coated outside the cable core from inside to outside. As a preferred technical solution, the temperature of high-temperature extrusion of the nanometer modified polytetrafluoroethylene composite material is 370-390 ℃; The outer sheath layer is formed by mixing and extruding polyether block amide elastomer and multi-walled carbon nanotubes. The comprehensive shielding signal cable and the manufacturing method thereof provided by the application have the following beneficial effects: 1) The comprehensive shielding signal cable and the manufacturing method thereof provided by the application realize full-band shielding efficiency for the first time through the gradient composite structure of the iron-based amorphous nanocrystalline alloy layer (low-frequency magnetic shielding), the 3D woven mesh layer (medium-frequency electromagnetic shielding) and the conductive polymer coating layer (high-frequency electric field shielding), and the echo loss is greatly reduced, so that the electromagnetic transmission performance and reliability of the cable are improved, and the structural stability of the cable is improved. 2) The iron-based amorphous nanocrystalline alloy layer (low-frequency magnetic shielding) has a magnetic permeability > 50000 at a frequency of 1 kHz, has high magnetic permeability, can effectively guide low-frequency magnetic field lines, reduces magnetic resistance through magnetic bypass effect, significantly attenuates low-frequency magnetic field interference below 100 kHz, and avoids grain boundary defects through the amorphous structure, thereby improving the structural stability of the material. The 3D woven mesh layer (medium-frequency electromagnetic shielding) suppresses medium-frequency (100 kHz-1 GHz) electromagnetic interference through reflection and absorption mechanisms, and can balance flexibility and shielding efficiency when the coverage rate is ≥ 95%, and the 3D woven mesh layer structure enhances mechanical strength and reduces signal leakage caused by deformation of the shielding layer during bending. The conductive polymer coating layer (high-frequency electric field shielding) absorbs high-frequency electric field energy above 1 GHz through surface impedance matching and high-frequency eddy current loss, reduces echo loss, and avoids the influence of traditional metal layers on the flexibility of the cable through the lightweight characteristics. The iron-based amorphous nanocrystalline alloy layer, the 3D woven mesh layer and the conductive polymer coating layer are respectively for low, medium and high frequency bands, and the three layers of materials cooperatively attenuate electromagnetic waves layer by layer through gradient impedance design to reduce secondary reflection. The iron-based amorphous nanocrystalline alloy layer provides rigid support, the 3D braided mesh layer enhances the bending resistance, and the conductive polymer coating fills the micro gaps, and the overall tensile strength is improved after the three are combined; The high-frequency absorption of the conductive polymer coating and the magnetic permeability of the iron-based amorphous nanocrystalline alloy layer synergistically reduce the return loss. The design first synergizes the iron-based amorphous nanocrystalline alloy layer (low-frequency magnetic shielding), the 3D braided mesh layer (medium-frequency electromagnetic shielding), and the conductive polymer coating (high-frequency electric field shielding) to realize full-band shielding effectiveness of the cable, while greatly reducing the return loss. Not only does this improve the electromagnetic transmission performance and reliability of the cable, but also improves the structural stability of the cable. BRIEF DESCRIPTION OF DRAWINGS Figure 1 A structural schematic diagram of a comprehensive shielding signal cable is provided. Among them, 1 is an insulating single wire; 2 is a conductor; 3 is an insulating layer; 4 is a filling rope; 5 is a composite shielding layer; and 6 is an outer sheath layer. DETAILED DESCRIPTION The preferred embodiments of the present application will be described in detail below with reference to the accompanying drawings. As shown in the drawings, Figure 1 The present application provides a comprehensive shielding signal cable, which comprises a cable core and a sheath layer wrapped outside the cable core. The sheath layer comprises, from inside to outside, a composite shielding layer 5 and an outer sheath layer 6. The composite shielding layer 5 comprises, from inside to outside, an iron-based amorphous nanocrystalline alloy layer, a 3D braided mesh layer, and a conductive polymer coating. The present application provides a comprehensive shielding signal cable, which comprises a cable core and a sheath layer wrapped outside the cable core. The sheath layer comprises, from inside to outside, a composite shielding layer 5 and an outer sheath layer 6. The composite shielding layer 5 comprises, from inside to outside, an iron-based amorphous nanocrystalline alloy layer, a 3D braided mesh layer, and a conductive polymer coating. Preferably, as shown in the drawings, Figure 1 The iron-based amorphous nanocrystalline alloy layer is Fe (70～75) Cu (0.5～1.5) Nb (2～4) Si (12～15) B (8～10) The amorphous nanocrystalline alloy layer is formed by longitudinally wrapping an iron-based amorphous nanocrystalline alloy strip, and the longitudinal wrapping overlap rate is ≥ 30%. Fe (70～75) Cu (0.5～1.5) Nb (2～4) Si (12～15) B (8～10)The Cu element and the Nb element in the amorphous nanocrystalline alloy layer cooperatively regulate the nanocrystalline formation: the Cu element promotes the uniform nucleation of the α-Fe(Si) phase, the Nb element inhibits the grain growth, and the synergistic effect makes the magnetic permeability of the iron-based amorphous nanocrystalline alloy layer be greater than 50,000 at a frequency of 1 kHz, thereby significantly improving the magnetic field conduction efficiency; the Fe (70～75) Cu (0.5～1.5) Nb (2～4) Si (12～15) B (8～10) The Si element content (12-15%) in the alloy layer ensures a high saturation magnetic induction (Bs≈1.94T) and enhances the magnetic flux carrying capacity; The traditional high-frequency cable (such as the RG series or Cat6A) is prone to shielding layer fracture due to repeated bending when transmitting at a high frequency (>1 GHz). The longitudinal wrapping overlap ratio of the cable is preferably greater than or equal to 30%, and a continuous magnetic flux path is formed in the overlapping area to avoid a sudden increase in magnetic resistance caused by the gap between the strips, thereby reducing the risk of magnetic leakage. The overlapping structure improves the mechanical engagement between the layers, disperses stress during bending, inhibits strip cracking or delamination, and significantly improves the structural stability. Preferably, as shown in Figure 1 The 3D woven mesh layer is a three-dimensional mesh structure woven by silver-plated copper wires and carbon fibers at a crossing angle of 40°-50°. The surface coverage of the 3D woven mesh is greater than or equal to 95%, and the mass ratio of the silver-plated copper wires to the carbon fibers is (5.5-7):(3-4.5). The traditional high-frequency cable (such as the RG series or Cat6A) is prone to signal attenuation due to the sharp increase in copper conductor resistance at high frequencies and the significant skin effect. The dielectric loss of the carbon fibers in cooperation with the silver-plated copper wires can compensate for this defect. A high proportion of silver-plated copper wires ensures basic conductivity and reduces the surface impedance to less than 0.1 Ω / sq. The 40°-50° crossing angle weaving makes the fiber stress direction and the axial direction form an optimal angle, thereby increasing the tensile strength by 20% (compared to orthogonal weaving) and prolonging the bending fatigue life by 3 times. Three-dimensional interlacing inhibits layer delamination, and the interlayer shear strength reaches 45 MPa (compared to 28 MPa for traditional weaving). The inner iron-based amorphous nanocrystalline alloy layer has a magnetic permeability greater than 50,000 at a frequency of 1 kHz. After guiding a low-frequency magnetic field, the woven mesh blocks medium-frequency radiation through a high coverage rate (≥95%). Preferably, as shown in Figure 1 The conductive polymer coating comprises the following components in the following mass percentages: Poly(3,4-ethylenedioxythiophene) 92%-96%; Polystyrene sulfonate 4%-8%; The thickness of the conductive polymer coating is 15-25 μm. Poly(3,4-ethylenedioxythiophene) (PEDOT) as the main component provides a conductivity of >1000S / cm (theoretical value of pure PEDOT), dominates the electromagnetic wave reflection mechanism, and has a shielding effectiveness (SE) of >70dB in the frequency band >10GHz; polystyrene sulfonate (PSS) as a dopant enhances the order of the poly(3,4-ethylenedioxythiophene) (PEDOT) molecular chain, reduces carrier scattering, and has a surface resistance of <1Ω / sq, thereby improving the conductivity; polystyrene sulfonate (PSS) forms ion channels to promote charge migration and enhance the coating's absorption loss of electromagnetic waves (the measured absorption ratio is ≈40%). Excessive polystyrene sulfonate (PSS) will reduce conductivity, so it is strictly limited to 1% to 14% to ensure charge transfer efficiency; the thickness of the conductive polymer coating is 15 to 25μm to avoid impedance mutation caused by being too thin, and the measured SE in the full frequency band (100kHz-100GHz) is >90dB. Preferably, if Figure 1 As shown, the cable core includes: a plurality of insulating single wires 1, and the insulating single wires 1 include: Conductor 2 is formed by twisting multiple strands of silver-plated copper wires, wherein the silver-plated copper wires include: a copper wire and a silver-plated layer covering the outside of the copper wire, wherein the thickness of the silver-plated layer is ≥ 2 μm; An insulating layer 3 covering the outside of the conductor 2, wherein the thickness of the insulating layer is 0.75 to 0.85 mm and the insulating layer 3 is a nano-modified polytetrafluoroethylene composite insulating layer; The conductor 2 is a silver-plated Category 7 stranded conductor, which is made of 19 strands of silver-plated copper wire with a diameter of 0.32 mm. The thickness of the silver coating is ≥ 2 μm, ensuring skin depth coverage at a bandwidth of 2.5 GHz. When traditional high-frequency cables (such as RG series or Cat6A) transmit at high frequencies (>1GHz), the ordinary PE / PVC insulation layer has a large dielectric constant (>2.3) and loss factor, and the dielectric loss is high. The insulation layer 3 described in this application is preferably a nano-modified polytetrafluoroethylene composite insulation layer. The dielectric constant of the nano-modified polytetrafluoroethylene composite insulation layer is increased to 2.06~2.15, and the loss factor (Df) is as low as 0.0002~0.0005, which is 1~2 orders of magnitude lower than PE / PVC (Df>0.02), thereby reducing the dielectric loss. Preferably, if Figure 1 As shown, the nano-modified polytetrafluoroethylene composite material insulation layer 3 contains polytetrafluoroethylene and 5-10nm silicon dioxide nanoparticles, and the mass proportion of the silicon dioxide nanoparticles is 1% to 5%; 5-10nm silica nanoparticles fill the micron-sized pores of the polytetrafluoroethylene matrix, eliminating local electric field distortion and stabilizing the dielectric constant at 2.06-2.15 at frequencies >1GHz; The high resistivity of silica nanoparticles (>10 16 Ω·cm) blocks the leakage current path, and a 1% to 5% mass ratio can reduce the dielectric loss tangent (tanδ) to 0.0002@1MHz, reducing signal transmission energy consumption. Preferably, if Figure 1 As shown, the cable core includes: multiple filling ropes 4, which are PP tear mesh filling ropes. They have the advantages of light weight, softness, flexibility, and strong compressive resistance, which greatly improves the structural strength of the cable. Preferably, if Figure 1 As shown, the outer sheath layer 6 includes the following components in mass percentage: Polyether block amide elastomer base material 78-82%; Multi-walled carbon nanotubes 18-22%; The thickness of the outer sheath layer 6 is greater than 1.5 mm; Multi-walled carbon nanotubes form a three-dimensional network in the polyether block amide elastomer matrix, which increases the tensile strength by more than 18% and enhances the deformation resistance through interfacial stress transfer; The polyether soft segment of the polyether block amide elastomer matrix imparts elasticity, and the multi-walled carbon nanotubes inhibit molecular chain slippage. The thickness of >1.5mm buffers stress, and the bending life is >5 million times (drag chain cable standard), which enhances mechanical strength. Traditional high-frequency cables (such as the RG series or Cat6A) are prone to cracking of the outer sheath layer due to repeated bending during high-frequency (>1GHz) transmission. The outer sheath layer 6 described in this application contains 1.5-3% carbon nanotubes by mass to form a conductive path, and the volume resistivity is reduced to 104-106Ω·cm, thereby preventing charge accumulation from causing breakdown. The outer sheath layer 6 gives the cable excellent properties such as high mechanical strength, strong temperature resistance, anti-static and anti-deformation capabilities. On the other hand, the present invention also provides a method for manufacturing a comprehensive shielded signal cable, which is prepared by obtaining a comprehensive shielded signal cable as described in any one of the above items, comprising the following steps: A plurality of silver-plated copper wires are twisted together in a concentric twisting manner to form a conductor 2, wherein the twist pitch is ≤12 times the diameter of the conductor 2; The nano-modified polytetrafluoroethylene composite material is extruded and coated on the outside of the conductor 2 at high temperature, and then irradiated and cross-linked after cooling to form an insulated single wire 1; Twisting at least two insulated single wires 1 and a filling rope 4 together to form a cable core; The outside of the cable core is covered with a composite shielding layer 5 and an outer sheath layer 6 from the inside to the outside; The method realizes the performance of wide frequency band, high shielding and bending resistance of the cable through the synergistic effect of four technologies of conductor optimization (electric field control), nanomodified polytetrafluoroethylene composite insulating layer (dielectric reinforcement), composite shielding layer (wideband anti-interference) and outer sheath layer modification (mechanics / environmental protection), and the cable is suitable for 5G communication, medical imaging and military electronics fields and has high safety and reliability. Preferably, the temperature for high-temperature extrusion of the nanomodified polytetrafluoroethylene composite is 370-390 DEG C; The outer sheath layer is formed by mixing and extruding polyether block amide elastomer added with multi-walled carbon nanotubes, and specifically includes the following steps: Material pretreatment: polyether block amide drying: drying in a vacuum oven or air oven at 60-80 DEG C for 4-8 hours; multi-walled carbon nanotube drying: drying in a vacuum oven or air oven at 100-120 DEG C for 2-4 hours; Pre-dispersion: pre-mixing 18-22% of the dried multi-walled carbon nanotubes with 78-82% of the polyether block amide elastomer in a high-speed mixer to form a master batch; The master batch is mixed and extruded to form the outer sheath layer, and the mixing equipment is preferably a co-rotating twin-screw extruder, which has excellent dispersion and mixing capacity, can flexibly control the temperature in sections, can set multiple feeding ports and exhaust ports, and has a narrow residence time distribution, wherein the processing temperature is: feeding section: 170-190 DEG C, melting / mixing section: 190-220 DEG C, metering / homogenization section: 190-210 DEG C, head / die: 190-210 DEG C; High-temperature extrusion of the nanomodified polytetrafluoroethylene composite eliminates pores inside the material, and radiation crosslinking makes the dielectric constant fluctuate ≤±0.05 (1 MHz), avoiding phase distortion of high-frequency signals. Example 1 As shown in Figure 1 The present application provides a comprehensive shielding signal cable, comprising: a cable core and a sheath layer wrapped outside the cable core, the sheath layer sequentially comprises a composite shielding layer 5 and an outer sheath layer 6 from inside to outside; The composite shielding layer 5 comprises: an iron-based amorphous nanocrystalline alloy layer, a 3D braided mesh layer and a conductive polymer coating layer arranged from inside to outside outside the cable core; the iron-based amorphous nanocrystalline alloy layer is Fe 73.5 Cu1Nb3Si 13.5 B9 amorphous nanocrystalline alloy layer, the Fe 73.5 Cu1Nb3Si 13.5B9 amorphous nanocrystalline alloy layer thickness is 0.1mm, permeability > 50000(1kHz), the iron-based amorphous nanocrystalline alloy layer is formed by iron-based amorphous nanocrystalline alloy tape longitudinal package, the longitudinal package overlap rate is 30%; the 3D woven mesh layer is formed by the 3D mesh structure of the silver-plated copper wire and the carbon fiber with a 45° crossing angle, the surface coverage of the 3D woven mesh is 95%, and the mass ratio of the silver-plated copper wire and the carbon fiber is 6:4; the conductive polymer coating is composed of the following components with a mass percentage of 94% of poly(3,4-ethylenedioxythiophene) and 6% of polystyrene sulfonate; the thickness of the conductive polymer coating is 20μm, and the surface resistance is <1Ω / sq; The cable core comprises two insulated single wires 1 and two filling ropes 4, the two insulated single wires 1 and the two filling ropes 4 are twisted to form the cable core, the two insulated single wires 1 are correspondingly arranged, and the two filling ropes 4 are correspondingly arranged, the insulated single wire 1 comprises a conductor 2 and an insulating layer 3 wrapped outside the conductor 2, the conductor 2 is a silver-plated Class 7 twisted conductor, which is twisted by 19 silver-plated copper wires with a diameter of 0.32 mm, the silver-plated copper wire comprises a copper wire and a silver-plated layer wrapped outside the copper wire, and the thickness of the silver-plated layer is 2μm; the skin depth coverage under 2.5GHz frequency bandwidth is ensured; the thickness of the insulating layer 3 is 0.8mm, and the insulating layer 3 is a nano-modified polytetrafluoroethylene composite insulating layer; the nano-modified polytetrafluoroethylene composite insulating layer contains 5-10nm silicon dioxide nanoparticles, and the mass percentage of the silicon dioxide nanoparticles is 1%-5%, and the filling rope 4 is a PP tear net film filling rope; The outer sheath layer 6 comprises the following components with a mass percentage of 80% of polyether block amide elastomer base material; 20% of multi-walled carbon nanotubes; the thickness of the outer sheath layer 6 is 2mm. The outer sheath layer 6 contains 2% of carbon nanotubes in terms of mass percentage, that is, a conductive path is formed, the volume resistivity is reduced to 105Ω·cm, the charge accumulation is avoided to cause breakdown, and the sheath layer makes the cable have excellent properties such as high mechanical strength, strong temperature resistance, strong antistatic and anti-deformation ability. In another aspect, the application also provides a manufacturing method of the comprehensive shielding signal cable, and the comprehensive shielding signal cable is prepared by the following steps: The 19 silver-plated copper wires with a diameter of 0.32mm are twisted in a concentric manner to form the conductor 2, wherein the lay length is ≤12 times the diameter of the conductor; The nano-modified polytetrafluoroethylene composite material is extruded at a high temperature of 380℃ to wrap outside the conductor 2, and after cooling, the insulated single wire 1 is formed by electron beam irradiation crosslinking; The two prepared insulated single wires 1 and the two PP tear net film filling ropes 4 are twisted together by a high-speed star twisting machine to form the cable core; The cable core is coated from inside to outside with an iron-based amorphous nanocrystalline alloy layer, a 3D braided mesh layer, and a conductive polymer coating composite shielding layer to form a composite shielding layer 5, and the composite shielding layer 5 is coated on the outside with an outer sheath layer 6 formed by extrusion molding after mixing of polyether block amide elastomer added with multi-walled carbon nanotubes, and specifically includes the following steps: Material pretreatment: polyether block amide drying: drying in a vacuum oven or air oven at 70°C for 6 hours; multi-walled carbon nanotube drying: drying in a vacuum oven or air oven at 110°C for 3 hours; Pre-dispersion: pre-mixing the dried 20% multi-walled carbon nanotubes with 80% polyether block amide elastomer in a high-speed mixer to make a master batch; The master batch is extruded after mixing to form an outer sheath layer, and the mixing equipment is preferably a co-rotating twin-screw extruder, which has excellent dispersion and mixing capacity, flexible segmented temperature control, multiple feeding and exhaust ports, and narrow residence time distribution, wherein the processing temperature is: feeding section: 180°C, melting / mixing section: 205°C, metering / homogenization section: 200°C, head / die: 200°C. The performance of the comprehensive shielding signal cable obtained in Test Example 1 is as follows: 1. High frequency performance: attenuation <0.5 dB / m at 2.5 GHz, return loss >26 dB; 2. Shielding effectiveness: >120 dB in the frequency range of 1 MHz-10 GHz, and the attenuation of the iron-based amorphous nanocrystalline alloy layer to 50 Hz power frequency magnetic field is ≥40 dB; 3. Mechanical performance: attenuation change <5% after 10,000 cycles at a bending radius of 5D; 4. Environmental adaptability: characteristic impedance fluctuation <2Ω in the range of -40°C to 120°C. Therefore, the comprehensive shielding signal cable obtained in Example 1 realizes the performance of wide frequency band, high shielding, and bending resistance through the synergistic effect of four technologies of conductor optimization (electric field control), nanomodified polytetrafluoroethylene composite insulation layer (dielectric reinforcement), composite shielding layer (wideband anti-interference), and outer sheath layer modification (mechanical / environmental protection), and is suitable for 5G communication, medical imaging, military electronics, and other fields, with high safety and reliability. It is to be understood that the present application is described by way of example only, and that modifications or alterations can be made to the features and embodiments described without departing from the spirit and scope of the application. In addition, modifications can be made to the features and embodiments described to adapt them to particular situations and materials without departing from the spirit and scope of the application. Accordingly, the present application is not limited to the specific embodiments described herein, but rather only by the claims which follow, all variations and equivalents which fall within the ranges of the claims being intended to be embraced herein.

Claims

1. A comprehensive shielded signal cable, characterized in that: include: The cable core and the protective layer wrapped around the outside of the cable core, the protective layer includes a composite shielding layer and an outer sheath layer from the inside to the outside, and the composite shielding layer includes: an iron-based amorphous nanocrystalline alloy layer, a 3D braided mesh layer and a conductive polymer coating arranged from the inside to the outside of the cable core.

2. The integrated shielded signal cable according to claim 1, characterized in that: The iron-based amorphous nanocrystalline alloy layer is Fe (70～75) Cu (0.5～1.5) Nb (2～4) Si (12～15) B (8～10) The amorphous nanocrystalline alloy layer is formed by longitudinally wrapping the iron-based amorphous nanocrystalline alloy strips, and the longitudinal wrapping overlap rate is ≥30%.

3. The integrated shielded signal cable according to claim 1, characterized in that: The 3D woven mesh layer is a three-dimensional mesh structure woven by silver-plated copper wire and carbon fiber at a cross angle of 40° to 50°. The surface coverage of the 3D woven mesh is ≥95%, and the mass ratio of the silver-plated copper wire to the carbon fiber is (5.5 to 7): (3 to 4.5).

4. The integrated shielded signal cable according to claim 1, characterized in that: The conductive polymer coating comprises the following components in percentage by mass: Poly(3,4-ethylenedioxythiophene) 92% to 96%; Polystyrene sulfonate 4% to 8%; The thickness of the conductive polymer coating is 15 to 25 μm.

5. The integrated shielded signal cable according to claim 1, characterized in that: The cable core comprises: a plurality of insulating single wires, wherein the insulating single wires comprise: The conductor is formed by twisting multiple strands of silver-plated copper wires, wherein the silver-plated copper wires include: a copper wire and a silver-plated layer covering the outside of the copper wire, and the thickness of the silver-plated layer is ≥ 2 μm; The insulating layer coated on the outside of the conductor has a thickness of 0.75 to 0.85 mm and is a nano-modified polytetrafluoroethylene composite insulating layer.

6. The integrated shielded signal cable according to claim 5, characterized in that: The nano-modified polytetrafluoroethylene composite material insulating layer comprises polytetrafluoroethylene and 5-10 nm silicon dioxide nanoparticles, and the mass proportion of the silicon dioxide nanoparticles is 1%-5%.

7. The integrated shielded signal cable according to claim 5, characterized in that: The cable core comprises: a plurality of filling ropes, wherein the filling ropes are PP tear mesh filling ropes.

8. The integrated shielded signal cable according to claim 1, characterized in that: The outer sheath layer comprises the following components in percentage by mass: Polyether block amide elastomer base material 78-82%; Multi-walled carbon nanotubes 18-22%; The thickness of the outer sheath layer is greater than 1.5 mm.

9. A method for manufacturing a comprehensive shielded signal cable, characterized in that: The method of preparing the integrated shielded signal cable according to any one of claims 1 to 8 comprises the following steps: A conductor is formed by twisting multiple strands of silver-plated copper wire in a concentric lay, wherein the lay length is ≤12 times the conductor diameter; The nano-modified polytetrafluoroethylene composite material is extruded and coated on the outside of the conductor at high temperature, and then irradiated and cross-linked after cooling to form an insulated single wire; Twisting at least two insulated single wires and a filling rope together to form a cable core; The outside of the cable core is covered with a composite shielding layer and an outer sheath layer in sequence from the inside to the outside.

10. The method for manufacturing a comprehensive shielded signal cable according to claim 9, wherein: The temperature of high-temperature extrusion of the nano-modified polytetrafluoroethylene composite material is 370-390°C; The outer sheath layer is formed by mixing polyether block amide elastomer and multi-walled carbon nanotubes and then extruding.

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