WO2023122569A1

WO2023122569A1 - System and method of additive manufacturing for enhanced conductivity

Info

Publication number: WO2023122569A1
Application number: PCT/US2022/081991
Authority: WO
Inventors: Nirup Nagabandi; Joseph GERRINGER
Original assignee: Essentium Ipco, Llc
Priority date: 2021-12-24
Filing date: 2022-12-20
Publication date: 2023-06-29

Abstract

A three-dimensional (3D) printing method and system for enhanced conductivity are provided. The method comprises extruding a thermoplastic composite in successive layers to form a 3D part. The thermoplastic composite comprises a thermoplastic material having carbon fibers. The carbon fibers have a length of between 10 and 500 microns and an aspect ratio of between 1 and 100. The carbon fibers are between 5 and 50 weight percent of the thermoplastic material and are a conductive material reactive to an electromagnetic energy for enhanced conductivity. The method further comprises directing a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane. The method further comprises emitting the electromagnetic energy into the plasma. The plasma directs electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

Description

SYSTEM AND METHOD OF ADDITIVE MANUFACTURING FOR

ENHANCED CONDUCTIVITY

INTRODUCTION

[0001] The present disclosure relates to three-dimensional printing and more particularly systems and methods of three-dimensional printing of materials with customized and enhanced conductivity.

[0002] Manufacturing is an essential piece of business that has a substantial influence on the global supply chain. Additive manufacturing typically involves a plurality of components, multiple materials, and a conforming manufacturing method. Once an end use part of an application is perceived and the appropriate materials are selected, the method of manufacturing is chosen based on a desired end use part properties. However, many parts in which custom/tailored properties are desired are manufactured from multiple components and materials which may not be desirable. Additionally, there are limited feasible materials for use in additive manufacturing.

SUMMARY

[0003] Thus, while current manufacturing systems and methods achieve their intended purpose, there is a need for a new and improved system and method of additive manufacturing (or three-dimensional printing) an end use part having enhanced conductivity. Moreover, there is a need for a more robust material and manufacturing process in additive manufacturing. [0004] In one aspect of the present disclosure, a new and improved material that can yield custom properties based on manufacturing parameters within a single manufacturing platform has been developed. Such material and process serve to unlock design freedom and increase material flexibility, leading to more robust parts and a unification of multiple components into a single part. These improvements are achieved by way of the new material having tailored properties that may be adjusted based on the parameters of the manufacturing method used during part production.

[0005] In accordance with aspects of the present disclosure, a three- dimensional (3D) method, system, and apparatus for enhanced conductivity are provided. In one aspect, a three-dimensional (3D) printing method for enhanced conductivity is provided. The method comprises extruding a thermoplastic composite in successive layers to form a 3D part. The thermoplastic composite comprises a thermoplastic material having carbon fibers. The carbon fibers have a length of between 10 and 500 microns. The carbon fibers have an aspect ratio of between 1 and 100. The carbon fibers are between 5 and 50 weight percent of the thermoplastic material. The carbon fibers are a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation.

[0006] In this aspect, the method further comprises directing a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane. The plasma is directed at an angle perpendicular to the plane. The method further comprises emitting the electromagnetic energy of between 2 and 100 Watts into the plasma. The plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0007] In one example, the thermoplastic material further comprises carbon nanotubes. In another example, the carbon nanotubes is up to 10 weight percent of the thermoplastic material. In yet another example, the carbon nanotubes is up to 5 weight percent carbon of the thermoplastic material. In still another example, the carbon nanotubes are 1 weight percent of the thermoplastic material.

[0008] In an example, the aspect ratio of the carbon fibers is between 3 and 50. In another example, the aspect ratio of the carbon fibers is 10. In yet another example, the length of the carbon fibers is between 50 and 150 microns. In still another example, the length of the carbon fibers is 60 microns.

[0009] In one example, the carbon fibers being 5 and 25 weight percent of the thermoplastic. In another example, the carbon fibers being 10 weight percent of the thermoplastic. In yet another example, the electromagnetic energy is between 5 and 60 Watts.

[0010] In accordance with another aspect of the present disclosure, a three-dimensional (3D) printing system for enhanced conductivity is provided. The system comprises a 3D printer configured to print a 3D part by extruding successive layers of a thermoplastic composite comprising a thermoplastic material having carbon fibers. The carbon fibers have a length of between 10 and 500 microns. The carbon fibers have an aspect ratio of between 1 and 100. The carbon fibers are between 5 and 50 weight percent of the thermoplastic material. The carbon fibers are a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation.

[0011] The system further comprises a plasma emitter arranged to direct a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane. The plasma is directed at an angle perpendicular to the plane. The system further comprises an electromagnetic energy source arranged to generate and emit the electromagnetic energy of between 2 and 100 Watts into the plasma such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0012] In an embodiment, the thermoplastic material further comprises carbon nanotubes. In another embodiment, the carbon nanotubes is up to 10 weight percent of the thermoplastic material.

[0013] In one embodiment, the aspect ratio of the carbon fibers is between 3 and 50. In another embodiment, the length of the carbon fibers is between 50 and 150 microns. In yet another embodiment, the carbon fibers being 5 and 25 weight percent of the thermoplastic. In still another embodiment, the electromagnetic energy is between 5 and 60 Watts.

[0014] In accordance with another aspect of the present disclosure, an extrusion nozzle for a three-dimensional (3D) printer is provided. The nozzle comprises a nozzle body defining a filament extrusion channel having an extrusion end for extruding successive layers of a thermoplastic composite comprising a thermoplastic material having carbon fibers. The carbon fibers have a length of between 10 and 500 microns. The carbon fibers have an aspect ratio of between 1 and 100. The carbon fiber are between 5 and 50 weight percent of the thermoplastic material. The carbon fibers are a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation

[0015] The nozzle further comprises a plasma generating portion adjacent the extrusion end and arranged to discharge a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane. The plasma generating portion is arranged to discharge the plasma capable of conducting the electromagnetic energy of between 2 and 100 Watts such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0016] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

[0018] FIG. 1 is side view of apparatus implementing a 3D printing method for enhanced conductivity in accordance with one embodiment of the present disclosure. [0019] FIG. 2 is a semi-schematic cross-section view of a 3D printer nozzle implementing the 3D printing method of FIG. 1 for enhanced conductivity.

[0020] FIG. 3 is a schematic of an embodiment of a 3D printing system implementing the 3D printing method of FIG. 1 for enhanced conductivity in accordance with one embodiment of the present disclosure.

[0021] FIG. 4 is a flowchart of the 3D printing method implemented by the apparatus and system in FIGS. 1 -3 for enhanced conductivity in accordance with one example of the present disclosure.

DETAILED DESCRIPTION

[0022] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

[0023] The new and improved material and process of the present disclosure help fuel the adoption of additive manufacturing at the industrial scale. In one aspect, the new and improved material is a thermoplastic material for additive manufacturing of an end use part. The material yields variable electrical properties on different portions of the part based on manufacturing parameters. The material and method of the present disclosure combines a composite of thermoplastic with carbon fiber (CF) made into a filament fashion along with a process of applying a controllable electric field during 3D printing. The process of applying the electric field controls and affects CF orientation within the part to yield custom electrical and mechanical properties.

[0024] Moreover, the present disclosure relates to using atmospheric plasma as an electrical conduction pathway for the application of electromagnetic energy, such an alternating electric current or a direct electric current, onto a predetermined location of a 3D part for enhancing conductivity and improving the interlayer adhesive strength of 3D printed parts produced with material extrusion 3D printing. The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

[0025] Shown in FIG. 1 is a 3D printing apparatus and process 100 for printing 3D parts by extrusion deposition of a thermoplastic material 102 in droplets or continuous beads 103 in multiple layers. The 3D printing process 100 includes an extrusion nozzle 104 having a plasma generating portion 106, an electric current applicator source 108, and a platform bed 110. As shown, the electric current applicator 108 may be an integral part of the extrusion nozzle 104.

[0026] The 3D printing process 100 uses an atmospheric plasma 112 as an electrical conduction pathway for the application of electric current 114 at the point of extrusion 116 to enhance conductivity and to control the welding of interlayers 118 of the extruded thermoplastic materials 102. It is desirable that the atmospheric plasma 112 is substantially evenly disturbed between the nozzle 104 and the 3D part being printed for the conduction of the electric current 114 between the nozzle 104 and the 3D part. A substantially evenly distributed atmospheric plasma 112 means a volume of plasma having uniform intensity and power to provide a conductive pathway to enable even heating of the 3D part or at least a portion of the 3D part proximal to the extrusion nozzle

104. [0027] The extrusion nozzle 104 may be moved through a predetermined extrusion path in both horizontal and vertical directions by a computer-controlled mechanism (not shown) to print a 3D part having a predetermined shape and size. Alternatively, the platform bed 110 may be moved relative to the extrusion nozzle 104 or coordinated movements of both the nozzle 104 and platform 110 may be used to achieve the desired extrusion path in the x, y, and z directions.

[0028] As shown, the plasma generating portion 106 is arranged to discharge a plasma orthogonally (or normal) onto a surface of a predetermined location or printed location 116 on the 3D part defining a plane. The plasma generating portion is arranged to discharge the plasma capable of conducting electromagnetic energy, preferably between 2 and 100 Watts. As depicted, the electromagnetic energy is orthogonally directed to the plasma on the plane of the predetermined location 116 of the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0029] As also shown, the electric current applicator 108 emits electromagnetic energy of between 2 and 100 Watts into the plasma such that the electromagnetic energy is perpendicularly directed to the plasma on the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof. In another embodiment, the electromagnetic energy is between 5 and 60 Watts. It is to be understood that the electric current applicator source 108 may be disposed external or internal of the nozzle 104.

[0030] To induce a desired orientation and degree of orientation of the carbon fibers (detailed below) of the thermoplastic composite, the electromagnetic energy is applied normal to the plane of the predetermined location of the print surface while printing. In a typical extrusion-based printing system, the carbon fibers align with a print direction. However, when the electromagnetic energy or field is applied normal to the print surface, the electromagnetic energy will cause the carbon fibers to orient normal or perpendicular relative to the print direction. As a result, a carbon fiber network is formed across layers of printed filament material. Moreover, the strength of the electromagnetic energy can be varied to change the degree of orientation of the carbon fibers (and CNTs if desired) to achieve tailorable properties.

[0031] The thermoplastic material 102 is fed through the extrusion nozzle 104 in a form of a thermoplastic composite filaments 102. The thermoplastic material may include various polymers such as, but not limited to, polyamide nylon (PA), polylactide (PLA), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetherimide (PEI), polypropylene (PP), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), thermoplastic polyesters (PCTG), acrylonitrile butadiene styrene (ABS), thermoplastic polyurethane (TPU), polyphthalamide (PPA), polyphenylsulfone (PPSLI), polyethersulfone (PESLI), polyetherketoneketone (PEKK), polyphenylene sulfide (PPS), acrylonitrile styrene acrylate (ASA), polyarylsulfones (PSU), polycarbonate (PC), thermoplastic elastomers (TPE), thermoplastic vulcanisate (TPV), high density polyethylene (HDPE), LILTEM™ 9085, and PA-PPA.

[0032] The thermoplastic filament 102 further comprises carbon fibers that may be surface coated and/or embedded throughout its volume with materials having conductive properties that react to the electric current or absorbs the electric current to enhance conductivity and generate heat. It is desirable that sufficient heat is generated to weld the interlayers 118 of extruded thermoplastic materials 102, thus increasing the interlayer 118 bond strength throughout the body of the 3D printed part.

[0033] In one embodiment, the carbon fibers have a length of between 10 and 500 microns. In another embodiment, the length of the carbon fibers is between 50 and 150 microns. In a preferred embodiment, the length of the carbon fibers is 60 microns.

[0034] In this embodiment, the carbon fibers may have an aspect ratio (length to diameter or length to width) of between 1 and 100. In other embodiments, the carbon fibers may have an aspect ratio of between 3 and 50. In another preferred embodiment, the aspect ratio may be 10.

[0035] In one embodiment, the carbon fiber may be between 5 and 50 weight percent of the thermoplastic material. In another embodiment, the carbon fibers may be 5 and 25 weight percent of the thermoplastic. In a preferred embodiment, the carbon fibers may be 10 weight percent of the thermoplastic.

[0036] In the exemplary embodiments shown, the thermoplastic composite filaments 102 may also include carbon nanotubes (CNTs) that may be surface coated and/or embedded throughout the volume with materials having conductive properties that reacts to the electric current or absorbs the electric current to enhance conductivity and generate heat. The CNTs may include single-wall carbon nanotubes (SWNT), multi-walled carbon nanotubes (MWNT), and/or functionalized carbon nanotubes. Other forms of electric current absorbing nanomaterials, such as carbon black, buckyballs, graphene, and/or magnetic nanoparticles, can also be used.

[0037] In one embodiment, the carbon nanotubes may be up to 10 weight percent of the thermoplastic material. In another embodiment, the carbon nanotubes may be up to 5 weight percent carbon of the thermoplastic material. In a preferred embodiment, the carbon nanotubes may be 1 weight percent of the thermoplastic material.

[0038] Referring to both FIG. 1 and FIG. 2, the extrusion nozzle 104a is configured to heat the thermoplastic filament 102 to a molten state and extrude the molten thermoplastic material 102 in successive layers onto the platform bed 110 until the 3D part has been printed. The extrusion nozzle 104a includes a plasma generating portion 106 configured to generate an atmospheric plasma 112 for conducting electric current to weld the interlayers 118 of extruded composite material 102. As mentioned above, the plasma generating portion 106 is arranged to discharge a plasma orthogonally (or normal) onto a surface of a predetermined location or printed location 116 on the 3D part defining a plane. As shown in the embodiment of FIG. 2, the plasma generating portion is arranged to discharge the plasma capable of conducting electromagnetic energy, preferably between 2 and 100 Watts, such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location 116 on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0039] Shown in FIG. 2, the extrusion nozzle 104a includes a nozzle body 120 defining a filament extrusion channel 122 extending along an extrusion axis-A. The filament extrusion channel 122 includes a filament feed end 124 and an opposite filament extrusion end 126. The extrusion nozzle 104a further includes a heater element 128 in thermal contact with the extrusion channel 122. The heater element 128 melts the thermoplastic filament 102 to a molten state as the thermoplastic filament 102 is fed through the filament extrusion channel 122 from the feed end 124 to the extrusion end 126. Heat breaks 130 are provided adjacent the filament feed end 124 to insulate the extrusion nozzle 104a from the remainder of the 3D printer (not shown).

[0040] Coaxially disposed about the extrusion nozzle body 120 is a nozzle housing 132. The nozzle housing 132 cooperates with the nozzle body 120 to define a plasma generation channel 134 therebetween. The plasma generation channel 134 includes a gas inlet 136 and a plasma outlet 138 opposite the gas inlet 136 adjacent the extrusion end 126 of the filament extrusion channel 122. A pair of electrodes 140, 142 is disposed within the plasma generation channel 134. A pressurized stream of gas including, but not limited to, argon, helium, carbon dioxide, and air is induced through the plasma generation channel 134 from the inlet 136 to the outlet 138. The pressurized stream of gas may be generated via fans, blowers, pumps, or pressurized gas tanks. As the gas flows through the plasma generation channel, the pair of electrodes 140, 142 are configured to excite the gas to generate a plasma stream 112. The plasma stream 112 exits the plasma outlet 138 and is directed at the 3D part being printed.

[0041] Referring back to FIG. 1 , the electric current applicator source 108 is configured to emit an electric current 114 toward the plasma 112 produced by the extrusion nozzle 104. As discussed above, the electric current applicator 108 emits electromagnetic energy of between 2 and 100 Watts such that the electromagnetic energy is directed normal to the plasma on the plane of the predetermined location of the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof. In another embodiment, the electromagnetic energy is between 5 and 60 Watts.

[0042] The electric current 114 includes a predetermined frequency and power sufficient to react with the carbon fibers in the extruded thermoplastic materials 102 to generate sufficient heat to weld or fuse the interlayers of extruded thermoplastic material 102 into a solid integral structure. The electric current 114 can be focused upon the newly, or immediately, printed location 116 using the electric current applicator source 108 located immediate adjacent the nozzle 104. The application of electric current 114 adjacent the nozzle 104 generates localized heating 116 as the part is being printed. The electric current applicator source 108 can be attached to the printer head directly (or disposed internally therein) to move with the extrusion nozzle 104. This localized electric current heating allows for the electric current 114 to be applied during printing, with only the immediately-printed area being exposed rather than the entire volume of the 3D part. The nozzle 104a and electric current applicator source 108 may be used in conjunction with a thermoplastic material extrusion 3D printer either as a built-in feature or as an add-on kit to be connected to an existing 3D printer.

[0043] FIG. 3 is a schematic of an embodiment of a 3D printing system 200a implementing the 3D printing process and apparatus in FIGS. 1 -3 from a thermoplastic composite. As in the previous examples, the thermoplastic composite comprises a thermoplastic material having carbon fibers. In one embodiment, the carbon fibers have a length of between 10 and 500 microns. In another embodiment, the length of the carbon fibers is between 50 and 150 microns. In a preferred embodiment, the length of the carbon fibers is 60 microns.

[0044] In this embodiment, the carbon fibers may have an aspect ratio (length to diameter or length to width) of between 1 and 100. In other embodiments, the carbon fibers may have an aspect ratio of between 3 and 50. In another preferred embodiment, the aspect ratio may be 10. In one embodiment, the carbon fiber may be between 5 and 50 weight percent of the thermoplastic material. In another embodiment, the carbon fibers may be 5 and 25 weight percent of the thermoplastic. In a preferred embodiment, the carbon fibers may be 10 weight percent of the thermoplastic.

[0045] Moreover as mentioned above, the thermoplastic composite filaments 102 may also include carbon nanotubes (CNTs) that may be surface coated and/or embedded throughout the volume with materials having conductive properties that reacts to the electric current or absorbs the electric current to enhance conductivity and generate heat. The CNTs may include single-wall carbon nanotubes (SWNT), multi-walled carbon nanotubes (MWNT), and/or functionalized carbon nanotubes. Other forms of electric current absorbing nanomaterials, such as carbon black, buckyballs, graphene, and/or magnetic nanoparticles, can also be used.

[0046] In one embodiment, the carbon nanotubes may be up to 10 weight percent of the thermoplastic material. In another embodiment, the carbon nanotubes may be up to 5 weight percent carbon of the thermoplastic material. In a preferred embodiment, the carbon nanotubes may be 1 weight percent of the thermoplastic material. [0047] The system uses plasma as an electrical conduction pathway for the application of electromagnetic energy, such as an electric current (2 to 100 Watts), to enhance conductivity and fuse interlayers of 3D printed parts. The 3D printing system 200a includes an electromagnetic energy source 202 for generating an electric current, a plasma emitter 204, a 3D printer 206, a high voltage isolator 208, 3D printer controls 210, and a high voltage supply 212, which may include a direct current (DC) source, pulsed DC source, or alternating current (AC) source. The electromagnetic energy source 202 is powered by the high voltage supply 212.

[0048] The 3D printer 206 includes a 3D printer nozzle head, such as the extrusion nozzle 104a in FIG. 2, configured to allow a high voltage potential to be applied directly to the nozzle body, to an electrode near the print head, or to a collar surrounding the nozzles. This high voltage potential will excite either a distributed plasma cloud or a focused plasma stream directed at the 3D printed parts. The plasma emitter 204 requires a high voltage source 212, a control unit to manage the voltage and current during the print, and certain circuit isolation 208 shielding requirements necessary to isolate the high voltage potential from damaging or interfering with the electronic 3D printer controls 210. The plasma emitter is arranged to direct a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane. Thus, the plasma is directed at an angle perpendicular or normal to the plane.

[0049] The electromagnetic energy source is arranged to generate and emit the electromagnetic energy into the plasma. More specifically, the electromagnetic energy source is arranged to emit the electromagnetic energy of between 2 and 100 Watts into the plasma such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0050] It is desirable to combine optimal plasma distribution and electromagnetic heating to produce optimal 3D print conductivity and strength improvement. The electromagnetic energy applied through the plasma could come from the plasma generating high voltage electronics. The electromagnetic energy is applied directly to the 3D printer nozzles 104a concentrically around the nozzle body 120. A benefit is the ability to provide a local conduction pathway for the coupling of the electric current applicator 108 to the 3D part being printed. The plasma is produced near the 3D printer nozzle 104a and directed at a local region where the electric current energy is to be dissipated. The plasma interacts with the conductive thermoplastic in such a way as to provide an ionized electron pathway either to or from the electric current applicator source 108 located at or near the nozzle 104.

[0051] In accordance with an example of the present disclosure, FIG. 4 shows a flowchart of a three-dimensional (3D) printing method 310 for enhanced conductivity. As shown, the method comprises in step 312 extruding a thermoplastic composite in successive layers to form a 3D part. The thermoplastic composite comprises a thermoplastic composite comprising a thermoplastic material having carbon fibers. In one embodiment, the carbon fibers have a length of between 10 and 500 microns. In another embodiment, the length of the carbon fibers is between 50 and 150 microns. In a preferred embodiment, the length of the carbon fibers is 60 microns. [0052] The thermoplastic material may include various polymers such as, but not limited to, polyamide nylon (PA), polylactide (PLA), polyetheretherketone (PEEK), polyetherketoneketone

(PEKK), polyetherimide (PEI), polypropylene (PP), polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG), thermoplastic polyesters (PCTG), acrylonitrile butadiene styrene (ABS), thermoplastic polyurethane (TPU), polyphthalamide (PPA), polyphenylsulfone (PPSLI), polyethersulfone (PESLI), polyetherketoneketone (PEKK), polyphenylene sulfide (PPS), acrylonitrile styrene acrylate (ASA), polyarylsulfones (PSU), polycarbonate (PC), thermoplastic elastomers (TPE), thermoplastic vulcanisate (TPV), high density polyethylene (HDPE), ULTEM™ 9085, and PA-PPA.

[0053] In this embodiment, the carbon fibers may have an aspect ratio (length to diameter or length to width) of between 1 and 100. In other embodiments, the carbon fibers may have an aspect ratio of between 3 and 50. In another preferred embodiment, the aspect ratio may be 10. In one embodiment, the carbon fiber may be between 5 and 50 weight percent of the thermoplastic material. In another embodiment, the carbon fibers may be 5 and 25 weight percent of the thermoplastic. In a preferred embodiment, the carbon fibers may be 10 weight percent of the thermoplastic.

[0054] Moreover as mentioned above, the thermoplastic composite filaments 102 may also include carbon nanotubes (CNTs) that may be surface coated and/or embedded throughout the volume with materials having conductive properties that reacts to the electric current or absorbs the electric current to enhance conductivity and generate heat. The CNTs may include single-wall carbon nanotubes (SWNT), multi-walled carbon nanotubes (MWNT), and/or functionalized carbon nanotubes. Other forms of electric current absorbing nanomaterials, such as carbon black, buckyballs, graphene, and/or magnetic nanoparticles, can also be used.

[0055] In one embodiment, the carbon nanotubes may be up to 10 weight percent of the thermoplastic material. In another embodiment, the carbon nanotubes may be up to 5 weight percent carbon of the thermoplastic material. In a preferred embodiment, the carbon nanotubes may be 1 weight percent of the thermoplastic material.

[0056] The method 310 further comprises in step 314 directing a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane. The plasma is directed at an angle perpendicular to the plane.

[0057] Furthermore, the method 310 further comprises in step 316 emitting the electromagnetic energy of between 2 and 100 Watts into the plasma. The plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

[0058] It is to be understood that methods and systems discussed in the present disclosure may implement direct metal plating, involve tailored mechanical and electrical properties, and may be used for MIMO antennas. With the methods and systems of the present disclosure, component consolidation may be achieved. That is, multiple parts may be combined that have different electrical properties but now connected and processed as one complete part or as a single material for various material properties, including built-in sensor printing. Moreover, with the methods and systems of the present disclosure, direct metal plating or direct electroplating 3D printed plastic parts may also be achieved. That is, the 3D printed parts would exhibit electrical conductivities in the specified range for metal plating them directly without any need to post process. Further, parts can be self-masked by imparting no conductivity in the regions that do not need electroplating.

[0059] Moreover, with the methods and systems of the present disclosure, tailored mechanical properties may also be achieved. That is, parts can be made deliberately weaker or stronger in user-selected sections by effecting the CF orientation. Additionally, with the methods and systems of the present disclosure, tailored electrical properties may be implemented. That is, surface resistance can be controlled by the printing process to impart conductive, semi-conductive or insulative properties in selected sections by effecting the CF orientation. In addition, with the methods and systems of the present disclosure, printed sensors may be manufactured. That is, by incorporating relatively small sections of varying electrical properties, the printed part can function as a built-in force and/or stress gauge.

[0060] Further, with the methods and systems of the present disclosure, a custom EMI application may be achieved. That is, a custom EMI shield can be built. Moreover, with the methods and systems of the present disclosure, MIMO antennas can be built. That is, antennas needed for 5G could be manufactured in a single step.

[0061] As a result, customization along with material freedom and design freedom are enhanced making the manufacturing method and system more robust.

[0062] The description of the present disclosure is merely exemplary in nature and variations that do not depart from the gist of the present disclosure are intended to be within the scope of the present disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure.

Claims

CLAIMS What is claimed is:

1 . A three-dimensional (3D) printing method for enhanced conductivity, the method comprising: extruding a thermoplastic composite in successive layers to form a 3D part, the thermoplastic composite comprising a thermoplastic material having carbon fibers, the carbon fibers having a length of between 10 and 500 microns, the carbon fibers having an aspect ratio of between 1 and 100, the carbon fiber being between 5 and 50 weight percent of the thermoplastic material, the carbon fibers being a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation; directing a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane, the plasma being directed at an angle perpendicular to the plane; and emitting the electromagnetic energy of between 2 and 100 Watts into the plasma, wherein the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

2. The method of claim 1 wherein the thermoplastic material further comprises carbon nanotubes.

3. The method of claim 2 wherein the carbon nanotubes is up to 10 weight percent of the thermoplastic material.

4. The method of claim 2 wherein the carbon nanotubes is up to 5 weight percent carbon of the thermoplastic material.

5. The method of claim 2 wherein the carbon nanotubes is 1 weight percent of the thermoplastic material.

6. The method of claim 1 wherein the aspect ratio of the carbon fibers is between 3 and 50.

7. The method of claim 1 wherein the aspect ratio of the carbon fibers is 10.

8. The method of claim 1 wherein the length of the carbon fibers is between 50 and 150 microns.

9. The method of claim 1 wherein the length of the carbon fibers is 60 microns.

10. The method of claim 1 wherein the carbon fibers being 5 and 25 weight percent of the thermoplastic.

11 . The method of claim 1 wherein the carbon fibers being 10 weight percent of the thermoplastic.

12. The method of claim 1 wherein the electromagnetic energy is between 5 and 60 Watts.

13. A three-dimensional (3D) printing system for enhanced conductivity, the system comprising: a 3D printer configured to print a 3D part by extruding successive layers of a thermoplastic composite comprising a thermoplastic material having carbon fibers, the carbon fibers having a length of between 10 and 500 microns, the carbon fibers having an aspect ratio of between 1 and 100, the carbon fiber being between 5 and 50 weight percent of the thermoplastic material, the carbon fibers being a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation; a plasma emitter arranged to direct a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane, the plasma being directed at an angle perpendicular to the plane; and an electromagnetic energy source arranged to generate and emit the electromagnetic energy of between 2 and 100 Watts into the plasma such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

14. The system of claim 1 wherein the thermoplastic material further comprises carbon nanotubes.

15. The system of claim 2 wherein the carbon nanotubes is up to 10 weight percent of the thermoplastic material.

16. The system of claim 1 wherein the aspect ratio of the carbon fibers is between 3 and 50.

17. The system of claim 1 wherein the length of the carbon fibers is between 50 and 150 microns.

18. The system of claim 1 wherein the carbon fibers being 5 and 25 weight percent of the thermoplastic.

19. The system of claim 1 wherein the electromagnetic energy is between 5 and 60 Watts.

20. An extrusion nozzle for a three-dimensional (3D) printer comprising: a nozzle body defining a filament extrusion channel having an extrusion end for extruding successive layers of a thermoplastic composite comprising a thermoplastic material having carbon fibers, the carbon fibers having a length of between 10 and 500 microns, the carbon fibers having an aspect ratio of between 1 and 100, the carbon fiber being between 5 and 50 weight percent of the thermoplastic material, the carbon fibers being a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation; and a plasma generating portion adjacent the extrusion end and arranged to discharge a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane, the plasma generating portion arranged to discharge the plasma capable of conducting the electromagnetic energy of between 2 and 100 Watts such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

21 . A three-dimensional (3D) printing method for enhanced conductivity, the method comprising: extruding a thermoplastic composite in successive layers to form a 3D part, wherein the thermoplastic composite comprises a thermoplastic material having carbon fibers, the carbon fibers having a predetermined length, the carbon fibers having a predetermined aspect ratio, the carbon fiber having a predetermined weight percent of the thermoplastic material, the carbon fibers being a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation; directing a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane; and emitting the electromagnetic energy into the plasma, wherein the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.

22. A three-dimensional (3D) printing system for enhanced conductivity, the system comprising: a 3D printer configured to print a 3D part by extruding successive layers of a thermoplastic composite comprising a thermoplastic material having carbon fibers, the carbon fibers having a predetermined length, the carbon fibers having a predetermined aspect ratio, the carbon fiber being a predetermined weight percent of the thermoplastic material, the carbon fibers being a conductive material reactive to an electromagnetic energy for enhanced conductivity and heat generation; a plasma emitter arranged to direct a plasma orthogonally onto a surface of a predetermined location on the 3D part defining a plane; and an electromagnetic energy source arranged to generate and emit the electromagnetic energy into the plasma such that the plasma directs the electromagnetic energy perpendicular to the plane of the predetermined location on the 3D part to control an orientation of the carbon fibers and a degree of the orientation thereof.