Apparatus and method for additive manufacturing

Abstract

A manufacturing method and apparatus for additive manufacturing, comprising: an environmental chamber defining an interior, a platform on which an object is built in a powder bed within the interior of the environmental chamber, a nitrogen supply coupled to the interior of the environmental chamber, a laser that creates an ion channel extending to powder, and a power supply that applies electrical energy to the ion channel, the electrical energy being transmitted to the powder in the powder bed through the ion channel.

Description

[0001] This application is a divisional application of the invention patent application with application number 201911235640.X filed on December 5, 2019 and invention name “Apparatus and method for additive manufacturing”. Technical Field

[0002] The present disclosure relates to a method and apparatus for manufacturing an object by additive manufacturing. Background Art

[0003] In contrast to subtractive manufacturing methods, which remove material, additive manufacturing processes typically involve the buildup of one or more materials to create an object. Additive manufacturing can be utilized to form a wide variety of parts with both simple and complex geometries. Summary of the invention

[0004] In one aspect, the present disclosure relates to a method of manufacturing an object by additive manufacturing, the method comprising providing a molecule-rich environment, creating a laser-induced plasma channel in the molecule-rich environment to a portion of powder in a powder bed, and applying electrical energy to the laser-induced plasma channel, wherein the electrical energy is transmitted to the powder in the powder bed through the laser-induced plasma channel, wherein at least energy from the electrical energy melts or sinters the portion of the powder in the powder bed.

[0005] In another aspect, the present disclosure relates to an apparatus for additive manufacturing, the apparatus comprising an environmental chamber defining an interior, a powder bed within the interior of the environmental chamber, a gas supply selectively fluidly coupled to the interior of the environmental chamber, an irradiation source that irradiates a portion of the powder in the powder bed, the irradiation creating an ion channel extending to the powder, and a power source that applies electrical energy to the ion channel, the electrical energy being transmitted to the powder in the powder bed through the ion channel.

[0006] In another aspect, the present disclosure is directed to a cooling module comprising a metal substrate and an aluminum silicon carbide metal matrix composite heat sink integrally formed with at least a portion of the metal substrate, wherein the aluminum silicon carbide metal matrix composite heat sink is configured to be operably coupled to a heat generating electronic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In the attached picture:

[0008] Figure 1 is a perspective view of an aircraft having an electronics chassis according to various aspects described herein.

[0009] Figure 2 According to various aspects described herein, it may include Figure 1 A perspective view of an exemplary power module in an electronic chassis.

[0010] Figure 3 yes Figure 2 Cross-sectional view of the power module along line III-III.

[0011] Figure 4 is a schematic diagram of an additive manufacturing apparatus according to aspects described herein.

[0012] Figure 5 According to the aspects described herein, Figure 4 Schematic diagram of the additive manufacturing of the device. DETAILED DESCRIPTION

[0013] Aspects of the present disclosure relate to additive manufacturing; specifically, applying electrical pulses through laser induced plasma channels (LIPC) or "ion channels" for use in a three-dimensional metal printing process. Among other things, aspects of the present disclosure can be used to manufacture heat sinks for electronic chassis, or power modules for aircraft, or methods for any metal and non-metal parts including inhomogeneous metal and non-metal parts. Among other things, aspects of the present disclosure also relate to the formation of aluminum silicon carbide (AL SiC) metal matrix composites (MMCs) by LIPC induced by an ultraviolet (UV) laser beam in a pressurized nitrogen-rich environment.

[0014] Typically, during additive manufacturing, a free-standing object is manufactured from a computer-aided design (CAD) model. Laser sintering or melting is an additive manufacturing process used to rapidly manufacture functional prototypes, parts, and tools. Selective laser sintering, direct laser sintering, selective laser melting, and direct laser melting are common industrial terms used to refer to the manufacture of three-dimensional objects by sintering or melting fine powders using a laser beam. Sintering requires melting (agglomerating) powder particles at a temperature below the melting point of the powder material, while melting requires complete melting of the powder particles to form a solid homogeneous substance. The physical processes associated with laser sintering or laser melting involve heat transfer to the powder material, which then sinters or melts the powder material. Although laser sintering and melting processes can be applied to a wide range of powder materials, the scientific and technological aspects of the production pathway, such as the sintering or melting rate and the influence of processing parameters on the evolution of the microstructure during layer manufacturing, are complex. This manufacturing method is accompanied by multiple modes of heat, mass, and momentum transfer, as well as chemical reactions that complicate the process. Current selective laser melting 3D printing processes have many disadvantages compared to standard manufacturing processes. These disadvantages include, for example, reduced strength due to incomplete sintering of metal powder particles, which is common in additive manufacturing processes, and high levels of residual stresses due to highly concentrated localized heat application. Other disadvantages are related to porosity issues, which have recently been observed in the development of cold plates used to cool high-power electronic power conversion products that provide thermal management for silicon carbide electronic components.

[0015] Additionally, issues associated with current additive manufacturing processes using infrared lasers or direct lasers are that multiple phase changes and complex microstructures often result in thermal residual stresses. Rapid heating and cooling rates (ΔT ~ 1,000 to 100,000K / s) result in suppressed phase changes, supersaturated phases, segregation, hot cracks, and thermal residual stresses. Direct metal laser melting and other such processes have low efficiencies of about 25% or less due to the direct use of the laser to produce melting of the particles. Unidirectional heat flow into the build plate or substrate results in textured grains and anisotropic properties. Each layer is subjected to repeated heating and cooling cycles, resulting in temperatures that may exceed Tliq or Therefore, infrared lasers currently used in additive manufacturing are not efficient for producing complex metal parts. With faster manufacturing processes, increased heating is required. Various aspects of the innovation disclosed herein create value by introducing electrical pulses through LIPC to increase the heating efficiency of lasers used in additive manufacturing. In addition, this innovation focuses on advanced LIPC technology by using ultraviolet (UV) lasers in a high-pressure nitrogen atmosphere to create LIPC. It will be understood that various aspects of the disclosure can be used in conjunction with conventional infrared selective laser sintering, or can be used as a standalone process.

[0016] Although a "set" of multiple elements will be described, it will be understood that a "set" may include any number of corresponding elements, including only one element. It will also be understood that the gas used to conduct the electrical pulses is not limited to nitrogen, and may constitute other gases or gas mixtures whose molecules can be excited by the laser beam. In addition, all directional references (e.g., radial, axial, up, down, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise) are used only for identification purposes to help the reader understand the present disclosure, and do not create limitations, particularly limitations on their position, direction or use. Connection references (e.g., attachment, connection, connection and engagement) will be interpreted broadly, and unless otherwise indicated, may include intermediate elements between sets of elements, as well as relative movement between elements. Therefore, connection references do not necessarily infer that two elements are directly connected and are in a fixed relationship to each other. The exemplary drawings are for illustrative purposes only, and the dimensions, positions, orders and relative sizes reflected in the drawings may vary.

[0017] It should be understood that while the cooling module is disclosed for illustrative purposes of the manufacturing process and its applicability, it should be understood that the process can be used to additively manufacture any suitable larger or smaller object, such as but not limited to components of or layers thereon of an aircraft engine, or for that matter, any homogeneous or inhomogeneous metal or non-metal part for any application (non-limiting examples include parts for power generation, medical systems / components, optical imaging, electronics, automotive, space system parts manufacturing, etc.). Further, while the cooling module may have general applicability, the aircraft environment and specific applications of avionics chassis and electrical components will be described in further detail. Aircraft avionics have increasingly demanding requirements and higher power density in smaller spaces, and therefore increasingly demanding requirements for power dissipation devices. New power generation units, conversion units, or transistors may require new materials and more efficient electrical and thermal management.

[0018] Figure 1 An aircraft 2 is schematically shown having an avionics system 4, which is shown as an onboard electronics chassis 6 (shown in phantom) for housing avionics or avionics components for use in operation of the aircraft 2. It will be appreciated that the avionics system 4 may include thermal management components having heat spreaders, heat sinks, heat exchangers, radiators, or heat pipes, in non-limiting examples. The electronics chassis 6 may house a variety of power modules 10 ( Figure 2 ), and protect against contaminants, electromagnetic interference (EMI), radio frequency interference (RFI), vibration, etc. Alternatively or additionally, the electronic chassis 6 can have a variety of avionics equipment mounted thereon. It will be understood that the electronic chassis 6 can be located anywhere within the aircraft 2, not just the nose as shown. Although shown in a commercial airliner, the electronic chassis 6 and power module 10 can be used in any type of aircraft, such as but not limited to fixed wings, rotary wings, rockets, commercial aircraft, personal aircraft, and military aircraft. In addition, aspects of the present disclosure are not limited to aircraft aspects, and can be included in other mobile and fixed configurations. Non-limiting example mobile configurations can include land-based, water-based, or other air-based vehicles, as well as power generation, medical systems / components, optical imaging, electronics, automobiles, ships, submarines, manufacturing of space system parts, etc.

[0019] Figure 2 1 is a power module 10 according to aspects of the present disclosure, which includes a set of electronic devices 12, a substrate 14 and a base plate 18. The power module 10 can be located in an electronic chassis 6 ( Figure 1). In one aspect of the present disclosure, non-limiting examples of the electronic device 12 may include insulated gate bipolar transistors (IGBTs), metal oxide semiconductor field effect transistors (MOSFETs), diodes, metal semiconductor field effect transistors (MESFETs), and high electron mobility transistors (HEMTs) for applications not limited to avionics applications, automotive applications, oil and gas applications, etc. According to aspects disclosed herein, the electronic device 12 may be made of a variety of semiconductors, non-limiting examples of which include silicon, silicon carbide, gallium nitride, and gallium arsenide. The electronic device 12 may generate heat during operation.

[0020] A substrate 14 may be provided to avoid electrical short circuits and to perform heat exchange between the cooling module 19 and the electronic device 12. In one aspect disclosed herein, the substrate 14 is an electrically insulating and thermally conductive layer, such as a ceramic layer. Non-limiting examples of ceramic layers may include aluminum oxide, aluminum nitride, beryllium oxide, and silicon nitride. In a non-limiting example, the cooling module 19 may be directly bonded to the substrate 14. The substrate 14 may be coupled to the cooling module 19 and the electronic device 12 using a variety of techniques including, but not limited to, brazing, bonding, diffusion bonding, soldering, or pressure contact (e.g., clamping) to provide a simple assembly process. It should be noted herein that the exemplary arrangements described with respect to the power module 10 and the cooling module 19 are for illustrative purposes only and are not meant to be limiting.

[0021] Figure 3 2 is a cross-sectional view, more clearly showing that the heat generating component of the electronic device 12 can be bonded to the substrate 14 via the first conductive layer 22. In addition, the substrate 14 can be bonded to the thermal pad 23 via the second conductive layer 20. The first conductive layer 22 and the second conductive layer 20 can be any suitable layer, including but not limited to the example copper layer. In another aspect disclosed herein, an aluminum layer, a gold layer, a silver layer or an alloy layer can preferably replace the copper layer.

[0022] It will be appreciated that the thermal pad 23 may be optional. The optional thermal pad 23 may include a thermally conductive material, such as a carbon composite, a metal, or a thermally conductive paste, and may be positioned in thermal contact so that heat may be conducted therein. Regardless of whether the thermal pad 23 is included, the power module 10 may be mounted to the cooling module 19 to carry heat away from the electronic device 12.

[0023] By way of non-limiting example, the substrate 18 and the heat sink 16 are shown as being included in the cooling module 19. In the example shown, the substrate 18 is a liquid cooling substrate operably coupled to the thermal pad 23 in any suitable manner. At least one cooling manifold is disposed within the substrate 18 and includes a plurality of channels 21 that intersect to form spaced cavities through which a cooling fluid (not shown) can flow during operation. A plurality of channels 21 are shown, and the plurality of channels 21 are connected to each other to form a cooling channel loop in the substrate 18. Other structures such as internal heat transfer fins (not shown) may also be included in the channels 21. The flow of cooling fluid through the substrate 18 may be controlled as desired and will not be described in detail herein. The cooling fluid may be any suitable cooling fluid, as a non-limiting example, a mixture of propylene glycol, ethylene glycol, fuel, oil, refrigerant and water, and other coolants. Therefore, when the electronic device 12 is operably coupled to the cooling module 19, the cooling fluid flowing through the channels 21 of the substrate 18 provides cooling of the electronic device 12.

[0024] The heat sink 16 forms part of the cooling module 19 and is shown as being integrally formed with the base plate 18. The heat sink 16 can be any suitable heat sink, including that it can be MMC, which can include, but is not limited to aluminum, copper, aluminum SiC (AlSiC) or aluminum graphite. As shown in cross section, the heat sink 16 contacts the base plate 18 in a manner that enables the cooling fluid in the channel 21 from the base plate 18 to be directly cooled to the heat sink 16, although this is not required. The remainder of this disclosure will focus on the heat sink 16 as an AlSiC MMC heat sink. Such a heat sink 16 formed of AlSiC MMC will have a thermal expansion coefficient that is more compatible with the substrate 14 of the power module 10 and will minimize the thermal expansion coefficient mismatch. Using AlSiC material is beneficial because AlSiC material has a low thermal expansion coefficient and it has a conductive heat transfer performance slightly lower than aluminum. AlSiC is also a good substitute for ceramic substrates.

[0025] It will be appreciated that conventional 3D laser sintering of MMC is not feasible and currently machining using diamond tools is very expensive. The disadvantage of current manufacturing processes is that it is difficult to machine these parts. This is because the silicon carbide particles have a high wear resistance, which requires the use of diamond tools. In addition, machine operation is expensive and limited. Likewise, the joining of dissimilar materials cannot be accomplished in a cost-effective manner.

[0026] Aspects of the present disclosure relate to SiC MMC layers, including AlSiC MMC layers manufactured by the LIPC additive manufacturing process, which are deposited on top of an aluminum liquid cooled base plate 18. This method is cost effective and provides the ability to manufacture complex shapes.

[0027] Figure 4 1 is an illustration of an additive manufacturing apparatus 100 according to aspects of the present disclosure that can be used to build a part 102 layer by layer in a powder bed 104 within a controlled environment 105. The powder bed 104 can be supplied by a powder dispenser (not shown). It will be understood that the controlled environment 105 can be any suitable closed manufacturing configuration configured to be controlled in any suitable manner. Here, the controlled environment 105 is sealable and configured to remain pressurized. A pressurized nitrogen supply 107 is selectively fluidly coupled to the controlled environment 105 and is configured to provide nitrogen 109 (schematically shown by arrows) into the controlled environment 105. Any suitable valve or control mechanism (not shown) can be included to control the supply and its pressurization.

[0028] Part 102 can be constructed by using laser power supply 106. Laser power supply 106 supplies power to ultraviolet laser 108, which emits a beam to mirror 110. The beam is reflected from mirror 110 to focusing lens 112. Focusing lens 112 can be, for example, an optical lens to focus and transmit the energy of the laser beam emitted by ultraviolet laser 108.

[0029] The apparatus 100 also includes a power supply 116 to provide electrical pulses to the focusing lens 112. The laser power supply 106 and the power supply 116 may be connected to a function generator 120 and controlled by a programmable controller or controller 118. The controller 118 may be, for example, a programmable proportional, integral, derivative controller that provides dual laser and electrical power pulse control.

[0030] According to one aspect, during operation, nitrogen 109 is introduced into the controlled environment 105 via the nitrogen supply 107 until the internal pressure increases. As a non-limiting example, nitrogen 109 may be supplied until the internal pressure increases by 30 psi during the forming process and maintained at that pressure. The power supply 116 is then controlled so that the ultraviolet laser 108 emits a laser beam 111 into a certain space above the powder bed 104. The laser beam 111 emitted by the ultraviolet laser 108 rapidly excites and ionizes the surrounding gas (including the supplied nitrogen 109) and forms an ionization path to guide the electrical pulse provided by the power supply 116. The ionized surrounding gas forms a plasma, which forms a conductive uniform plasma channel 114. Then, the electrical pulse provided by the power supply 116 may be applied through the plasma channel 114 to heat and combine the metal powder in the powder bed 104, thereby building the part 102.

[0031] As in Figure 5As more clearly shown in the schematic diagram of FIG. 1 , the ultraviolet laser 108 essentially emits a laser beam 111 into a high pressure nitrogen environment, shown generally at 109, above a metal powder, shown generally at 136. The metal powder 136 in this example is aluminum and contains silicon carbide 134 particles. The laser beam 111 rapidly heats, effectively excites and ionizes the pressurized nitrogen molecules, and forms an ionized path for the plasma to guide and conduct electrical pulses; such a path is the LIPC 114. The LIPC 114 is an electrically conductive and uniform plasma path or channel that essentially forms a plasma filament. Electrical pulses 130 are then applied to the metal powder 136 and silicon carbide 134 particles through the LIPC 114 to effectively heat and bond the metal powder 136 and silicon carbide 134 to form an AlSiC MMC. The silicon carbide provides a reinforcement effect in the resulting MMC.

[0032] It should be understood that the laser beams generated by the UV laser and the electrical pulses can be applied simultaneously or interleaved with each other after a short delay. It will also be understood that the laser can be used only to create a plasma channel for the electrical pulses to pass through, and the electrical pulses are used for the sintering and melting processes without the aid of the laser to assist the sintering and melting processes. In another non-limiting example, the laser can be used as an additional heating source or can be used in combination with the electrical pulses through the LIPC 114.

[0033] Aspects of the present disclosure result in faster, more efficient manufacturing of higher quality mechanical parts than conventional additive manufacturing processes that use lasers to directly heat metal powders. Traditionally, as a simplified example, for a 120-watt power supply, a laser power supply with 80 watts and a power supply with 40 watts can be combined to apply 120 watts of power to a target. Due to the losses associated with converting electrical energy into a laser beam, only about 25% of the power emitted by the 80-watt laser power supply (i.e., 20 watts) can be utilized. When the laser power reaches the target value, about 70% of the 20 watts from the laser are used to melt the powder; that is, about 14 watts of power are supplied from the 80-watt laser power supply. According to one aspect of the present disclosure, the power supply may apply a 40-watt electrical pulse to the LIPC generated by the 80-watt laser power supply. About 90% of the 40 watts applied from the power supply (i.e., 36 watts) can be utilized at the powder bed. Thus, according to aspects of the present disclosure, 36 watts of power from the power supply combined with 14 watts of power from the laser power supply allows a total power of 50 watts to be applied to melt the target.

[0034] It has been determined that the production of LIPC 114 depends on the number of molecules in its pathway; therefore, in a controlled environment 105 ( Figure 4) is added with nitrogen 109 until a high pressure nitrogen environment is reached to increase the LIPC current. It has also been determined that the measured current increases with increasing nitrogen pressure. Further, the absorption spectrum of nitrogen is significantly better in the ultraviolet spectrum than in the infrared spectrum. For a 248nm ultraviolet krypton fluoride laser, the laser photon energy is 5.013eV, the photon energy of a 10.6μm carbon dioxide infrared laser is 0.1173eV, and the ionization potential of a nitrogen molecule is 15.58eV. The number of photons required to ionize a nitrogen molecule is approximately 4 for an ultraviolet laser and approximately 133 for an infrared laser. Therefore, according to the current aspects of the present disclosure, additive manufacturing using electrical pulses of ultraviolet-induced LIPC applies approximately four times the heat to the target as conventional additive manufacturing methods. Based on the above, ultraviolet lasers provide a significantly more efficient way to generate plasma. In addition, when a high pressure nitrogen environment is integrated, the LIPC current will increase 10 times when the pressure increases by 30psi. The combined advantages of an integrated UV laser and a pressurized nitrogen atmosphere can significantly improve LIPC production efficiency.

[0035] Aspects of the present disclosure provide a number of benefits associated with additive manufacturing via LIPC using an ultraviolet laser in a nitrogen-rich or high-pressure nitrogen environment. Nitrogen-rich refers to a nitrogen level that contains more nitrogen than typical air. In one example, nitrogen-rich can include a pressurized nitrogen space that replaces typical air or otherwise occupies space around a manufacturing asset. Such a process increases the efficiency of the manufacturing process by more than fifty percent, thereby increasing manufacturing speed and reducing costs. Aspects of the present disclosure result in reduced residual stresses due to localized heating. In addition, due to the increased efficiency in the additive manufacturing process, the boundary layer between dissimilar metals is better controlled by electrical pulses through the LIPC. AlSiC MMC outperforms traditional materials, improving the performance of aircraft components, aircraft structures, and electronics for a variety of applications. AlSiC MMC produced as disclosed herein has excellent stiffness and wear resistance, including high fatigue strength twice that of aluminum alloys, high thermal conductivity, and a customizable thermal expansion coefficient.

[0036] In light of the foregoing, aspects of the present disclosure provide a three-dimensional additive manufacturing process that can increase the reliability of manufactured parts, improve the mechanical properties of parts, and increase the efficiency of selective sintering processes. Various aspects of the present disclosure provide several advantages of using additive manufacturing for three-dimensional metal printing, such as, but not limited to, reduced deformation resistance, improved plasticity, simplified processes, improved system electrical energy efficiency, reduced costs through increased yields, reduced product defects, minimized voids, and improved affected metal properties. Various aspects of the present disclosure provide reduced voids and porosity, as well as the envisioned possibility of eliminating voids due to the rapid heating provided by electrical pulses. The bond between SiC particles and base metal powder is improved. The electrical pulses provided by LIPC disrupt the market as new products replace or reduce the scale of more complex, more expensive additive manufacturing solutions using inefficient lasers.

[0037] In addition to those configurations shown in the above figures, the present disclosure also contemplates many other possible configurations. For example, in a non-limiting example, two or more controllers 118 can control the heating process of more than one material during formation. In this regard, the heating rate of such materials can be controlled to produce or form additional parts more quickly while reducing the expansion effects of different materials. To the extent not yet described, the different features and structures of each aspect can be used in combination with other aspects as needed. The fact that a feature cannot be shown in all aspects does not mean that it cannot be explained, but is for the sake of description simplicity. Therefore, regardless of whether the new aspect is explicitly described, the various features of different aspects can be mixed and matched as needed to form the new aspect. The combination or arrangement of the features described herein is covered by the present disclosure.

[0038] This written description uses examples to disclose various aspects of the invention, including the best mode, and also enables those skilled in the art to practice various aspects of the invention, including making and using any device or system and performing any incorporated method. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. These other examples are intended to fall within the scope of the claims if they have the same structural elements as the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

[0039] Further aspects of the invention are provided by the subject matter of the following clauses:

[0040] 1. A method for manufacturing an object by additive manufacturing, the method comprising: providing a molecule-rich environment; creating a laser-induced plasma channel in the molecule-rich environment to a portion of powder in a powder bed; applying electrical energy to the laser-induced plasma channel, wherein the electrical energy is transmitted to the powder in the powder bed through the laser-induced plasma channel, wherein at least energy from the electrical energy melts or sinters the portion of powder in the powder bed.

[0041] 2. A method according to any preceding clause, wherein creating the laser-induced plasma channel comprises emitting a laser beam from an ultraviolet laser.

[0042] 3. A method according to any preceding clause, wherein the molecule-rich environment is a nitrogen-rich environment.

[0043] 4. A method according to any preceding clause, wherein the nitrogen-rich environment is a high pressure nitrogen environment.

[0044] 5. A method according to any preceding clause, wherein the powder in the powder bed comprises aluminium powder and silicon carbide particles.

[0045] 6. A method according to any preceding clause, wherein providing a molecule-rich environment comprises supplying nitrogen to the sealed environment until the pressure increases by 30 psi.

[0046] 7. A method according to any preceding clause, wherein the electrical energy is supplied by a power supply.

[0047] 8. A method according to any preceding clause, wherein the electrical energy is a set of electrical pulses.

[0048] 9. A method according to any preceding clause, wherein electrical energy and said energy from said laser induced plasma channel are controlled to facilitate simultaneous melting or sintering of said portion of powder in said powder bed.

[0049] 10. A method according to any preceding clause, wherein electrical energy and said energy from said laser induced plasma channel are controlled to assist in sequentially melting or sintering said portion of powder in said powder bed.

[0050] 11. An apparatus for additive manufacturing, the apparatus comprising: an environmental chamber defining an interior; a powder bed within the interior of the environmental chamber; a gas supply selectively fluidly connected to the interior of the environmental chamber; an irradiation source that irradiates a portion of the powder in the powder bed, the irradiation creating an ion channel extending to the powder; and a power source that applies electrical energy to the ion channel, the electrical energy being transmitted to the powder in the powder bed through the ion channel.

[0051] 12. A method according to any preceding clause, wherein the radiation source is an ultraviolet laser.

[0052] 13. A method according to any preceding clause, wherein the ion channel is a laser induced plasma channel.

[0053] 14. A method according to any preceding clause, wherein the power source is a power supply.

[0054] 15. A method according to any preceding clause, wherein the electrical energy is electrical pulses.

[0055] 16. A method according to any preceding clause, wherein the gas supply is nitrogen.

[0056] 17. A method according to any preceding clause, wherein the environmental chamber is configured to be pressurised with a high pressure nitrogen supply.

[0057] 18. A cooling module, comprising: a metal substrate; and an aluminum silicon carbide metal matrix composite heat sink, wherein the aluminum silicon carbide metal matrix composite heat sink is integrally formed with at least a portion of the metal substrate, and wherein the aluminum silicon carbide metal matrix composite heat sink is configured to be operably connected to a heat-generating electronic device.

[0058] 19. A method according to any preceding clause, wherein the metal substrate is an aluminium metal substrate having a set of channels and configured for liquid cooling.

[0059] 20. The aluminum silicon carbide metal matrix composite heat sink is a 3D printed aluminum silicon carbide metal matrix composite heat sink.

Claims

1. A method for manufacturing an object by additive manufacturing, characterized in that The method comprises: Provides a molecule-rich environment; creating a laser-induced plasma channel in the molecule-rich environment to a portion of the powder in the powder bed; and applying electrical energy to the laser induced plasma channel, wherein the electrical energy is transmitted to the powder in the powder bed through the laser induced plasma channel, wherein at least energy from the electrical energy melts or sinters the portion of the powder in the powder bed; wherein creating the laser-induced plasma channel comprises emitting a laser beam; wherein the molecule-rich environment is a nitrogen-rich environment; wherein the nitrogen-rich environment is a high-pressure nitrogen environment; Wherein providing a molecule-rich environment comprises supplying nitrogen gas into the sealed environment until the pressure increases by 30 psi.

2. The method according to claim 1, characterized in that The powder in the powder bed includes aluminum powder and silicon carbide particles.

3. The method according to claim 1, characterized in that The electrical energy is supplied by a power supply.

4. The method according to claim 1, characterized in that: The electrical energy is a group of electrical pulses.

5. The method according to claim 1, characterized in that The electrical energy and the energy from the laser induced plasma channel are controlled to help simultaneously melt or sinter the portion of powder in the powder bed.

6. The method according to claim 1, characterized in that The electrical energy and the energy from the laser induced plasma channel are controlled to help successively melt or sinter the portion of powder in the powder bed.

7. The method according to claim 1, characterized in that Wherein creating the laser induced plasma channel includes emitting a laser beam from an infrared laser.

8. An apparatus for additive manufacturing, characterized in that: The device comprises: an environmental chamber defining an interior; a powder bed within the interior of the environmental chamber; a gas supply selectively fluidly coupled to the interior of the environmental chamber; an irradiation source that irradiates a portion of the powder in the powder bed, the irradiation creating ion channels extending to the powder; and a power source that applies electrical energy to the ion channels, the electrical energy being transmitted to the powder in the powder bed through the ion channels; wherein the irradiation source is a laser; wherein the environmental chamber is configured to be pressurized with a high pressure nitrogen supply; Wherein the pressurization with high pressure nitrogen supply refers to supplying nitrogen to the sealed environment until the pressure increases by 30 psi; The ion channel is a laser-induced plasma channel.

9. The device according to claim 8, characterized in that The power source is a power supply.

10. The device according to claim 8, characterized in that The electrical energy is an electrical pulse.

11. The device according to claim 8, characterized in that Wherein the gas supply is nitrogen.

12. The device according to claim 8, characterized in that The radiation source is an infrared laser.

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