Tool, manufacturing system and method for forming powder into a component

Abstract

A tool 10 comprising a die arrangement 12 to receive powder P; a punch arrangement 20 to apply pressure to the powder; a heating arrangement 14 comprising electrodes providing a current through the di

Description

Various tools for carrying out electric-field assisted forming, electric-field activated sintering and spark plasma sintering (SPS) are known. Micro-forming with field assisted sintering technology (micro-FAST) is a powder metallurgy method in which metallic or non-metallic materials are sintered using Joule heat generated by alternating electric current, and uniaxial pressure. Micro-FAST has process advantages in terms of the fast heating speed, high efficiency. Micro-FAST can also have advantages regarding the component being formed, such as finer grain size, including preserving the nanostructure of the material, and improved mechanical properties. However, existing sintering technologies have a number of drawbacks including only allowing for the forming of simple shapes, and being difficult to control both density and mechanical and physical properties of the formed part. SUMMARY In a first aspect there is provided a tool for forming powder into a component, the tool comprising: a die arrangement configured to receive the powder therein; a punch arrangement configured to move relative to the die arrangement to apply pressure to the powder; a heating arrangement configured to heat the powder, the heating arrangement comprising electrodes configured to provide a current through the die arrangement to heat the powder, wherein the electrodes are configured to move between a first configuration in which current is not provided to the die arrangement and a second configuration in which maximal current is provided to the die arrangement; a first actuator operable to reconfigure the electrodes between the first configuration and the second configuration to control heating of the powder; and a second actuator operable to move the punch arrangement relative to the die arrangement to control compressing of the powder; wherein the first and second actuators are configured to be independently operable. In use, the formed component may be a miniature component or a micro component. Miniature and micro components may be components in the submillimetre scale, e.g. components having at least two dimensions in the submillimetre range. The submillimetre range may be, for example, tens of microns. In use, the punch arrangement may be moved by the second actuator to apply pressure independently to the powder, up to 100 MPa. In use, the electrodes may be moved by the first actuator between the first configuration and the second configuration to control heating of the powder. Intermediate heating configurations may be available between the first configuration and the second configuration. There may be a number of discrete intermediate heating configurations, or a continually adjustable variation in intermediate heating configuration, depending on the nature of the first actuator. In use, the first actuator may reconfigure the electrodes from the first configuration to the second configuration to maximise heating of the powder. Alternatively, the first actuator may reconfigure the electrodes to an intermediate heating configuration to achieve a desired level of heating below the maximum. In use, the powder may be heated via Joule heating. Joule heating may be provided by an alternating current or a direct current, e.g. a pulsed direct current. Joule heating may be direct Joule heating or indirect Joule heating. The powder may be a conductive powder and heated via direct Joule heating. In the case of indirect Joule heating, conduction heating may also occur. For example, if the powder is non-conductive, then the heating arrangement may heat the die arrangement via Joule heating, and the die arrangement may heat the powder via conduction heating. Alternatively, in use, the powder may be heated via dielectric heating. Dielectric heating may be provided by an alternating electric field. The powder may be a dielectric powder, and heated via dielectric heating. Beneficially, the tool may enable the precise manufacturing of components, allowing for miniature components and micro components to be formed, and leading to higher accuracy, e.g. higher press precision, and higher quality in the formed components. This may be achieved due to the independent control of heating the powder and pressing the powder by the first and second actuators. The manufacture of miniature and micro components is applicable to a wide range of industries, including automotive, aviation, medical instruments, energy harvesters, superconductors, electronics, information technologies, robotics, cutting tools, etc. In the automotive industry, the tool may be utilized for precision manufacturing of small components, enhancing overall product quality. In the medical field, the tool’s ability to produce high-precision and intricate parts may be valuable for manufacturing medical instruments and devices. Additionally, the application of the tool in energy harvesters, superconductors, electronics, and cutting tools may address specific needs for miniaturization and advanced materials in these sectors. The first and second actuators, for independently controlling heating and compressing respectively, may provide greater process flexibility. Additionally, separate actuators for heating and compressing may contribute to easier and more effective quality control during the manufacturing process. The arrangement of the tool may allow for high temperatures in the component forming area, e.g. the sintering area, while keeping the temperatures of the electrodes and the main part of the tool, e.g. the actuators, low. Beneficially, this may prolong tool life, reduce production downtime, and lower tooling costs, addressing concerns from manufacturers. The improved process control and extended tool life may contribute to cost savings in the manufacturing process. Powder The powder may be a nano-structured powder. Nano-structured powder may be a powder with particle sizes of less than 100 nanometres in at least one dimension. The nano-structured powder may have a high surface area to volume ratio. The nanostructured powder may comprise or be formed of nanocrystalline Silicon Carbide, Aluminium Oxide nanoparticles, etc. Beneficially, in forming nano-strucutured powders, the tool may enable enhanced diffusion mechanisms crucial for densification. The tool may also lower the process time and temperature, to help in preserving small grain sizes of the nano-structured powder as it is formed into the component, which may enhance mechanical, chemical and electrical properties of the component. The powder may be a conductive powder or a non-conductive powder. The die arrangement may comprise or be formed of graphite, tungsten or ceramic, or silicon carbide. In particular, graphite may provide superior thermal and electrical properties, and may be easier and less expensive to machine. The die arrangement may be formed with a compound structure involving several different materials. The die arrangement may be configured to receive the punch arrangement therein. The heating arrangement, the die arrangement and the punch arrangement may be concentrically arranged. The die arrangement may separate the punch arrangement and the heating arrangement. The die arrangement may be generally elongate. The die arrangement may define a longitudinal axis. The die arrangement may comprise a guide portion. The guide portion may be configured to receive the punch arrangement therein. The electrodes, the guide portion of the die arrangement and the punch arrangement may be concentrically arranged. The guide portion of the die arrangement may separate the punch arrangement and the electrodes. The separation of the punch arrangement and the electrodes may allow for high temperatures in the sintering area while keeping the temperatures of the electrodes and the punch arrangement low. Beneficially, this may prolong tool life, reduce production downtime, and lower tooling costs, addressing concerns from manufacturers. The guide portion may be elongate. The guide portion may comprise first and second sub portions. The first and second sub portions may be elongate. The die arrangement may comprise a die portion. The die portion may be configured to receive the powder therein. The guide portion and the die portion may be separate components or may be integrally formed. The die portion may be received within the guide portion. Alternatively, the die portion may be positioned between the first and second sub portions of the guide portion. The die arrangement may define a chamber therein. The chamber may be elongate. The chamber may be rectangular, cylindrical, or some other elongate shape. The chamber may comprise a powder receiving portion. The powder receiving portion of the chamber may be defined by the die portion of the die arrangement. The powder receiving portion of the chamber may be configured to receive the powder. The powder receiving portion of the chamber may have a shape corresponding to the shape of the component to be formed. The powder receiving portion of the chamber may have a volume corresponding to the volume of the component to be formed. The chamber may comprise a punch receiving portion. The punch receiving portion may be defined by the guide portion of the die arrangement. The punch receiving portion of the chamber may be configured to receive the punch arrangement. The punch receiving portion of the chamber may comprise a first punch receiving portion and a second punch receiving portion. The first punch receiving portion of the chamber may be defined by a first sub portion of the guide portion of the die arrangement. The second punch receiving portion of the chamber may be defined by a second sub portion of the guide portion of the die arrangement. The punch receiving portion of the chamber may be contiguous with the powder receiving portion of the chamber. The die arrangement may comprise or be formed of a conductive material. In particular, the die portion of the die arrangement may comprise or be formed of a conductive material. The die portion may be configured to receive current from the electrodes. The die arrangement may be configured to transfer current to the powder to heat the powder, e.g. by Joule heating if the powder is a conductive powder, or by dielectric heating if the powder is a dielectric powder. Alternatively, the die arrangement may be configured to be heated by Joule heating and transfer heat to the powder by conduction, e.g. if the powder is a non-conductive powder. The punch arrangement may be configured to apply pressure directly to the powder. Alternatively, the punch arrangement may be configured to apply pressure to the powder via the die arrangement, e.g. a die portion of the die arrangement. The punch arrangement may be configured to apply a force to the powder up to a force capacity that is limited by the tool strength and fatigue life, e.g. 100 KN. The punch arrangement may be operationally separated from the heating arrangement, in particular the electrodes. The punch arrangement may be moveable in the chamber of the die arrangement, in particular the punch receiving portion of the chamber. The punch arrangement may be connected to the second actuator. Movement of the punch arrangement may be controlled by the second actuator. The punch arrangement may comprise an actuated punch. The actuated punch may be considered as an active punch. The actuated punch may be moveable within the guide portion of the die arrangement, in particular the first sub portion. The actuated punch may be moveable in the chamber, in particular the first punch receiving portion of the chamber. The actuated punch may be connected to the second actuator. Movement of the actuated punch may be controlled by the second actuator. The actuated punch may be configured to apply an actuated force to the powder. The actuated force may be a controlled force. The actuated force may be a predetermined force. The punch arrangement may further comprise a counter punch. The counter punch may be considered as a passive punch. The counter punch may be positioned within the guide portion of the die arrangement, in particular the second sub portion. The counter punch may be fixed in the chamber, in particular the second punch receiving portion of the chamber. The counter punch may resist the force applied to the powder by the actuated punch. The counter punch may be configured to apply a reaction force to the powder. The reaction force may balance the actuated force. Together the actuated force and the reaction force may compress the powder. The electrodes may be moveable relative to the die arrangement between the first configuration and the second configuration. The electrodes may be configured to heat the powder via the die arrangement. The electrodes may comprise or be formed of copper or other kinds of conductive materials. The electrodes may be generally annular. The electrodes may be configured to receive the die arrangement therein. The electrodes may be configured to receive the punch arrangement therein. The electrodes may be arranged around the die arrangement, in particular the guide portion of the die arrangement. The electrodes may comprise a pair of electrodes. The electrodes may be configured to heat the powder via Joule heating, e.g. direct or indirect Joule heating. The electrodes may be configured to generate an alternating current or a pulsed direct current. Alternatively, the electrodes may be configured to heat the powder via dielectric heating. The electrodes may be configured to generate an alternating electric field. The powder may be axially positioned between an upper part of the tool and a lower part of the tool, e.g. at an axial position between the electrodes. The electrodes may comprise a first electrode. The first electrode of the electrodes may be positioned around the actuated punch of the punch arrangement. The first electrode may be positioned around the first sub portion of the guide portion of the die arrangement. The first electrode may be an actuated electrode. The actuated electrode may be moveable to define the first configuration and the second configuration. The actuated electrode may be moveable relative to the die arrangement. The actuated electrode may be connected to the first actuator. Movement of the actuated electrode may be controlled by the first actuator. The electrodes may comprise a second electrode. The second electrode of the electrodes may be positioned around the counter punch of the punch arrangement. The second electrode of the pair of electrodes may be positioned around the second sub portion of the guide portion of the die arrangement. The second electrode may be a passive electrode. The passive electrode may have a fixed position. The tool may comprise a conductive member. The conductive member may be arranged around the die arrangement, in particular the die portion. The conductive member may be a separate component to the die arrangement. Alternatively, the conductive member may be integrally formed with the die arrangement, e.g. a flange extending from the die arrangement. The conductive member may be generally annular. The conductive member may be arranged between the electrodes, e.g. between the first electrode and the second electrode. The electrodes may be configured to be out of contact, e.g. spaced from, the conductive member in the first configuration. The electrodes may be configured to contact the conductive member in the second configuration. The electrodes may be configured to compress the conductive member in the second configuration. The conductive member may comprise or be formed of a conductive material. The conductive member may be configured to receive current from the electrodes. The conductive member may be configured to transfer current from the electrodes to the die arrangement, in particular the die portion of the die arrangement. In the first configuration a current path between the electrodes and the conductive member may be broken. In the second configuration a maximum current path between the electrodes and the conductive member may be formed. A maximum current may be transferred between the electrodes and the conductive member when the electrodes are in the second configuration. In the first configuration the actuated electrode may be spaced apart from the conductive member. In the second configuration the actuated electrode may be in contact with the conductive member. The actuated electrode may be configured to apply an actuated force to the conductive member in the second configuration. The actuated force may be a controlled force. The actuated force may be a predetermined force. The actuated force of the actuated electrode may be less than the actuated force of the actuated punch. The passive electrode may be positioned, e.g. a fixed position, in contact with the conductive member. The passive electrode may be in contact with the conductive member in both the first configuration and the second configuration. The passive electrode may support the conductive member. The passive electrode may resist the force applied to the conductive member by the actuated electrode. The passive electrode may be configured to apply a reaction force to the conductive member. The reaction force may balance the actuated force. Together the actuated force and the reaction force may compress the conductive member to ensure maximal contact between the electrodes and the conductive member and therefore a maximal current path. Actuators The first and / or second actuators may be double-acting actuators. The doubleacting actuators may provide benefits in accurately moving and stopping the electrodes and punch arrangement. The first actuator may be operable to reconfigure the electrodes relative to the die arrangement between the first configuration and the second configuration. The first actuator may be operable to reconfigure the electrodes relative to the conductive member between the first configuration and the second configuration. The first actuator may be operable to move the actuated electrode relative to the conductive member between the first configuration and the second configuration. The first actuator may be operable to move the actuated electrode, e.g. the contact surface, in and out of contact with the conductive member, e.g. the current receiving surface. In this way, the first actuator may control the flow of current between the electrodes, e.g. via the conductive member, and thereby control the heating of the powder. The first and / or second actuator may comprise a linear motor. The linear motor may have a high nominal speed, acceleration, accuracy and / or positioning repeatability. The linear motor may be a high-precision linear motor. The high-precision linear motor may permit implementation of a process control strategy to ensure precise and high-quality component formation. The strategy may involve optimization of the process parameters for heating and compressing. The tool may further comprise a control unit. The control unit may be configured to control the first and second actuators. The tool may further comprise a housing. The housing may define an environment in which the tool operates, e.g. the housing may be an atmosphere control housing. The operational environment may be inert gas. The inert gas may be sealed within the housing. The tool may further comprise or be connectable to an electric power source. The electric power source may provide an alternating current or a direct current, e.g. a pulsed direct current. The tool may be a sintering tool. The tool may be a hybrid electric-field-assisted-forming and electric-field-activated-sintering tool. The tool may be configured for forming miniature components and / or micro components. In a second aspect there is provided a method of forming powder into a component using the tool according to the first aspect. In a third aspect, there is a manufacturing system comprising: a sintering station, a cooling station, and a die-transport arrangement comprising a rotational table configured to transfer a die between the sintering station and the cooling station. The die-transport arrangement may enhance overall efficiency of a manufacturing process as well as allow for a compact manufacturing system, aiming at keeping an atmosphere protecting chamber of the manufacturing system small, leading to an energy saving. The sintering station may comprise a tool according to the first aspect. The sintering station may be operable to form a component from a powder. The diearrangement may be removable from the tool. The die-transport arrangement may be configured to move the die arrangement between the sintering station and the cooling station. The conductive member may be removable from the tool. The die-transport arrangement may be configured to move the conductive member between the sintering station and the cooling station. The die arrangement and conductive member may be retained together during transfer from the sintering station to the cooling station. The cooling station may be operable to cool the component, e.g. provide controlled cooling of the component. The cooling station may comprise a cooling arrangement. The cooling arrangement may comprise cooling elements. The cooling arrangement may be constructed in a corresponding manner to the heating arrangement of tool of the first aspect, the cooling elements corresponding to the electrodes. Additionally, the cooling elements may comprise fluid cooling channels, e.g. water cooling channels, extending there through. Once the die is transported to the cooling station, the cooling elements will be lowered to contact point, to provide enhanced and controllable cooling capacity to the die and powder. After the pre-defined cooling period, the cooling element will be retracted by the actuator. The cooling station may comprise a housing. The housing may define an environment, e.g. a controlled cooling environment. The temperature, humidity, etc. within the housing may be controlled. The cooling station may be construed in a corresponding manner to the tool of the first aspect, with the punch arrangement omitted. The system may allow for implementation of a process control strategy to ensure precise and high-quality component formation. The strategy may involve optimization of the process parameters for sintering, e.g. heating and compressing, and cooling stages. It should be understood that features defined above in accordance with any aspect of the present disclosure or below relating to any specific embodiment of the disclosure may be utilised, either alone or in combination with any other defined feature, in any other aspect or embodiment or to form a further aspect or embodiment of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1a is a cross-sectional schematic view of a tool in a first configuration; Figure 1b is a cross-sectional schematic view of the tool in a second configuration; Figure 2 is a cross-sectional perspective view of the punch arrangement, die arrangement and heating arrangement of the tool in the second configuration; Figure 3 shows an electro-thermal analysis for a cross-section of the tool in use; Figure 4 is a perspective view of the first and second actuators of the tool; and Figure 5 is a side view of a manufacturing system. DETAILED DESCRIPTION OF THE DRAWINGS Figures 1a and 1b are cross-sectional schematic views of a tool 10 for forming a powder P into a component. As shown in Figures 1a and 1b, the tool 10 comprises a die arrangement 12 configured to receive the powder P therein. The tool 10 comprises a heating arrangement 14 configured to heat the powder P. The heating arrangement 14 comprises electrodes 16 configurable between a first configuration (see Figure 1a) and a second configuration (see Figure 1b). A first actuator 18 is operable to reconfigure the electrodes 14 between the first configuration and the second configuration to control heating of the powder P. The tool 10 comprises a punch arrangement 20 configured to move relative to the die arrangement 12 to apply pressure to the powder P. Figure 1a shows the punch arrangement spaced apart from the powder P, e.g. applying no pressure to the powder P. Figure 1b shows the punch arrangement applying pressure to the powder P. A second actuator 22 is operable to control movement of the punch arrangement relative to the die arrangement to control compressing of the powder P. In use, the first and second actuators 18, 22 are configured to be independently operable. The first and second actuators 18, 22 independently controlling heating and compressing may provide greater process flexibility. The tool 10 may enable the precise manufacturing of components, allowing for miniature components and micro components to be formed, and leading to higher accuracy, e.g. higher press precision, and higher quality in the formed components. In use, the formed component may be a miniature component or a micro component. The electrodes 16 are configured to heat the powder via Joule heating. If the powder P is a conductive powder then it can be heated via direct Joule heating. Alternatively, if the powder P is a non-conductive powder then it can be heated via indirect Joule heating, e.g. the electrodes 16 heat the die arrangement 12 via Joule heating and the die arrangement 12 heats the powder P via conductive heating. In other embodiments the heating arrangement 14 may be configured to heat the powder, e.g. a dielectric powder, via dielectric heating. The structure of the tool 10 may allow for high temperatures in the sintering area, e.g. proximal the powder P in the die arrangement 12, while keeping the temperatures in the rest of the tool 10, e.g. the first and second actuators 18, 22, low. Beneficially, this may prolong tool life, reduce production downtime, and lower tooling costs, addressing concerns from manufacturers. Beneficially, improved process control and extended tool life may contribute to cost savings in the manufacturing process. In the illustrated tool 10, the electrodes 16, the die arrangement 12 and the punch arrangement 20 are concentrically arranged. The die arrangement 12 separates the punch arrangement 20 and the electrodes 16. Further detail of the die arrangement 12, heating arrangement 14 and punch arrangement 20 will be described with reference to Figures 2 and 3. The die arrangement 12 is generally elongate. The die arrangement defines a longitudinal axis L. The die arrangement 12 is configured to receive the punch arrangement 20 therein. The die arrangement 12 comprises a guide portion 24 configured to receive the punch arrangement 20 therein. The guide portion 24 of the die arrangement 12 separates the punch arrangement 20 and the electrodes 16. The guide portion 24 comprises first and second sub portions 24a, 24b. The die arrangement 12 comprises a die portion 26. The die portion 26 is configured to receive the powder P therein. In the illustrated tool 10, the guide portion 24 and the die portion 26 are integrally formed. However, it will be understood that the guide portion and the die portion may alternatively be separate components. The die portion 26 is located between the first and second sub portions 24a, 24b. In other embodiments the die portion 26 may be received within the guide portion 24 rather than between the first and second sub portions 24a, 24b of the guide portion 24. As shown in Figure 2, the die arrangement 12 defines a chamber 28 therein. The chamber 28 is generally elongate. The chamber 28 is generally rectangular, having a square cross-section across the longitudinal axis L of the die arrangement 12. The chamber 28 comprises a powder receiving portion 30 configured to receive the powder P. The powder receiving portion 30 is defined by the die portion 26 of the die arrangement 12. The powder receiving portion 30 has a shape corresponding to the desired shape of the component to be formed. The chamber 28 comprises a punch receiving portion 32. The punch receiving portion 32 is defined by the guide portion 24 of the die arrangement 12. The punch receiving portion 32 of the chamber 28 is configured to receive the punch arrangement 20 as discussed in more detail below. The punch receiving portion 32 of the chamber 28 comprises a first punch receiving portion 32a and a second punch receiving portion 32b. The first punch receiving portion 32a of the chamber 28 is defined by the first sub portion 24a of the guide portion 24 of the die arrangement 12. The second punch receiving portion 32b of the chamber is defined by the second sub portion 24b of the guide portion 24 of the die arrangement 12. The punch receiving portion 32 of the chamber 28 is contiguous with the powder receiving portion 30 of the chamber 28. The punch arrangement 20 is configured to apply pressure directly to the powder P. In other embodiments the punch arrangement may apply pressure to the powder indirectly, e.g. via the die portion of the die arrangement. The punch arrangement 20 is moveable in the chamber 28, in particular the punch receiving portion 32 of the chamber 28. The punch arrangement 20 comprises an actuated punch 34. The actuated punch 34 can be considered as an active punch. The actuated punch 34 is moveable within the guide portion 24 of the die arrangement 12, in particular the first sub portion 24a. The actuated punch 34 is moveable in the chamber 28, in particular the first punch receiving portion 32a of the chamber 28. Movement of the actuated punch 34 is controlled by the second actuator 22. The actuated punch 34 is configured to apply an actuated force to the powder P. The actuated force is a predetermined and controlled force. The punch arrangement 20 further comprises a counter punch 36. The counter punch 36 can be considered as a passive punch. The counter punch 36 is positioned within the guide portion 24 of the die arrangement 12, in particular the second sub portion 24b. The counter punch 36 is fixed in the chamber 28, in particular the second punch receiving portion 32b of the chamber 28. The counter punch 36 resists the force applied to the powder P by the actuated punch 34. The counter punch 36 is configured to apply a reaction force to the powder P, balancing the actuated force. The second sub portion 24b of the guide portion 24 of the die arrangement 12 defines a seat 38, e.g. in the form of a shoulder protruding into the second punch receiving portion 32b of the chamber 28. The seat 38 is configured to support the counter punch 36. In particular, the seat 38 is configured to support a head portion 40 of the counter punch 36. The head portion 40 of the counter punch 36 defines a wall 42, e.g. a radially extending wall, configured to engage the seat 38. The electrodes 16 are configured to receive the die arrangement 12 and the punch arrangement 20 therein. The electrodes 16 are generally annular. The electrodes 16 are arranged around the die arrangement 12, in particular the guide portion 24 of the die arrangement 12. The electrodes 16 comprise a pair of electrodes 16a, 16b. The powder P is axially positioned between the pair of electrodes 16a, 16b. A first electrode 16a of the pair of electrodes 16 is positioned around the actuated punch 34 of the punch arrangement 20. The first electrode 16a of the pair of electrodes 16 is positioned around the first sub portion 24a of the guide portion 24 of the die arrangement 12. A second electrode 16b of the pair of electrodes 16 is positioned around the counter punch 36 of the punch arrangement 20. The second electrode 16b of the pair of electrodes is positioned around the second sub portion 24b of the guide portion 24 of the die arrangement 12. The first electrode 16a is an actuated electrode. The actuated electrode 16a is moveable to define the first configuration and the second configuration. The actuated electrode 16a is moveable relative to the die arrangement 12. The actuated electrode 16a is connected to the first actuator 18. Movement of the actuated electrode 16a is controlled by the first actuator. The second electrode 16b is a passive electrode. The passive electrode 16b is fixed in its position. The tool 10 further comprises a conductive member 44. The conductive member 44 is generally annular, e.g. the conductive member 44 is a ring. The conductive member 44 is arranged around the die arrangement 12, in particular the die portion 26. The conductive member 44 comprises a first contact surface 44a. The first contact surface 44 contacts the die arrangement 12, in particular the die portion 26 of the die arrangement 12. The first contact surface 44a extends generally longitudinally, e.g. in a direction parallel to the longitudinal axis L of the die arrangement 12. The conductive member 44 is arranged between the first and second electrodes 16a, 16b. The conductive member 44 comprises a second contact surface 44b. The second contact surface faces the first electrode 16a, in particular a contact surface 17a of the first electrode 16a. The conductive member 44 comprises a third contact surface 44c, opposite the second contact surface 44b. The third contact surface 44c faces a contact surface 17b of the second electrode 16b. The second and third contact surfaces 44b, 44c extend generally laterally, e.g. in a direction transverse to the longitudinal axis L of the die arrangement 12. The second and third contact surfaces 44b, 44c are generally perpendicular to the first contact surface 44a. The first contact surface 44a extends between the second and third contact surfaces 44b, 44c. The passive electrode 16b has a fixed position in contact with the conductive member 44, e.g. the third contact surface 44c is fixed in contact with the contact surface 17b of the second electrode 16b. The passive electrode 16a supports the conductive member 44. The actuated electrode 16a is moveable relative to the conductive member 44. Movement of the actuated electrode 16a relative to the conductive member 44 is controlled by the first actuator. In the first configuration the actuated electrode 16a is spaced apart from the conductive member 44, e.g. the contact surface 17a of the actuated electrode 16a is spaced apart from the second contact surface 44b of the conductive member 44. The electrodes 16 are configured to compress the conductive member 44 in the second configuration. In the second configuration the actuated electrode 16a is in contact with the conductive member 44, e.g. the contact surface 17a of the actuated electrode 16a is in contact with the second contact surface 44b of the conductive member 44. The actuated electrode 16a is configured to apply an actuated force to the conductive member 44 in the second configuration. The actuated force is a controlled force. The actuated force of the actuated electrode 16a is less than the actuated force of the actuated punch 34. The passive electrode 16b resists the force applied to the conductive member 44 by the actuated electrode 16a. The passive electrode 16b is configured to apply a reaction force to the conductive member 44. The reaction force balances the actuated force. Together the actuated force and the reaction force compress the conductive member 44 to ensure maximal contact between the electrodes 16 and the conductive member 44. The tool 10 further comprises a housing 46. The housing 46 is configured to define an environment in which the tool 10 operates, e.g. the housing 46 is an atmosphere control housing. As shown in Figure 3, the tool 10 allows for high temperatures in the die portion 26 of the die arrangement 12 and the conductive member 44, e.g. the sintering area, while keeping the temperatures of the electrodes 16 low. The temperature distribution also represents current distribution. Areas with higher temperature indicate higher current density. As can be seen, a current path is provided between the electrodes 16. The conductive member 44 is formed of a conductive material. The conductive member 44 is configured to transmit current between the electrodes 16. The conductive member 44 is configured to receive current from the first electrode 16a and transfer current to the second electrode 16b. The conductive member 44 is configured to transfer current between the electrodes 16 and the die arrangement 12, in particular the die portion 26 of the die arrangement 12. In the first configuration the current path is broken or minimised due to the first electrode 16a being spaced apart from the conductive member 44. In the second configuration (shown in Figure 3) a maximum current flows along the current flow path due to maximal contact between the first electrode 16a and the conductive member 44, e.g. maximum current is transferred between the electrodes 16 and the conductive member 44. The die arrangement 12, in particular the die portion 26, is formed of a conductive material to form at least part of the current path between the electrodes 16. In the embodiment shown in Figure 3 the powder P is a conductive powder and the current flows through the powder P, heating the powder via Joule heating. The die arrangement 12 transfers current between the electrodes 16 and the powder P. In other embodiments, in which the powder P is a non-conductive powder, the current may flow through the electrodes 16 and die arrangement 12 but not the powder P. In this case the powder is heated via indirect Joule heating. The die arrangement is heated via direct Joule heating and the powder is heated by conductive heating from the die arrangement. Figure 4 shows the first and second actuators 18, 22 of the tool 10 in more detail. The first actuator 18 and the second actuator 22 of the tool 10 are double-acting actuators, e.g. they can provide both advancing and retracting movement. The second actuator 22 comprises a linear actuator 22a, e.g. a high-precision linear motor, for moving the actuated punch 34 so that the punch arrangement 20 compresses the powder P. The linear actuator 22a is arranged on the longitudinal axis L of the die arrangement. The first actuator 18 comprises two linear actuators 18a, 18b, configured to act together to move the actuated electrode 16a between the first configuration and the second configuration to control heating of the powder P by the heating arrangement 14. The linear actuators 18a, 18b are opposingly positioned either side of the linear motor 22a of the second actuator 22. In other embodiments there may be more than two linear motors, arranged around the linear actuator of the second actuator. The first actuator 19 comprises a frame 48. The frame 48 is arranged around the second actuator 22. The linear motors 18a, 18b are both connected to the frame 48 and configured to act together to move the frame. The actuated electrode 16a is mounted on the frame 48. The linear motors 18a, 18b control movement of the actuated electrode 16a via the frame 48. Figure 5 shows a manufacturing system 50 comprising a sintering station 52, a cooling station 54, and a die-transport arrangement 56 comprising a rotational table 58 configured to transfer a die arrangement 12 (not shown) between the sintering station 52 and the cooling station 54. The sintering station 52 comprises the tool 10 (some elements of the tool 10, e.g. the die arrangement and conductive member, are omitted for clarity). The cooling station 54 comprises a cooling arrangement. The cooling arrangement is similar to the heating arrangement of the tool 10, with differences as described below. The cooling arrangement comprises cooling elements 62, including an actuated element 62a and a passive element 62b. The elements 62 are configurable between a minimal cooling configuration and a maximal cooling configuration. The cooling station 54 comprises an actuator 64 operable to reconfigure the elements 62 between the minimal cooling configuration and the maximal cooling configuration. The elements 62 have cooling fluid channels (not visible) extending therethrough. The cooling station 54 is configured for connection to a cooling fluid supply, e.g. including a cooling fluid reservoir and a pump. The cooling fluid supply is configured to provide cooling fluid, e.g. water, to the cooling fluid channels of the elements 62. In use, the die arrangement is mounted on the rotational table 58. The actuated electrode 16a and actuated punch 34 are in a retracted position to allow die arrangement to be positioned at the sintering station 52. The tool 10 is used to heat and press powder into a component within the die arrangement 12, controlled by the first and second actuators, 18, 22 of the tool 10. Thereafter, the actuated electrode 16a and actuated punch 34 are returned to the retracted position, to allow the rotational table 58 to move the die arrangement to the cooling station. The conductive member is moved with the die arrangement. The actuated electrode 62a is also in a retracted position to allow the die arrangement to be positioned at the cooling station 54. Once the die arrangement 12 is transported to the cooling station 54, the actuated element 62a is lowered by the actuator 64 to contact the conductive member 44 and cool the formed component. After a pre-defined cooling period, the actuated element 62a is returned to the retracted position by the actuator 64 to allow the die arrangement 12 to be removed from the manufacturing system 50. The manufacturing system 50 further comprises a control unit 66. The control unit 66 is configured to control the first and second actuators 18, 22 of the sintering station 52, to control heating and pressing of the powder to form a component. The control unit is configured to control the actuator 64 of the cooling station 54, to control cooling of the formed component. It should be understood that features defined above in accordance with any aspect or specific embodiment of the disclosure may be utilized, either alone or in combination with any other defined feature, in any other aspect or embodiment or to 5 form a further aspect or embodiment of the disclosure.

Claims

1. A tool for forming a powder into a component, the tool comprising:a die arrangement configured to receive the powder therein;a punch arrangement configured to move relative to the die arrangement to apply pressure to the powder;a heating arrangement configured to heat the powder, the heating arrangement comprising electrodes configured to provide a current through the die arrangement to heat the powder, wherein the electrodes are configured to move between a first configuration in which current is not provided to the die arrangement and a second configuration in which maximal current is provided to the die arrangement;a first actuator operable to reconfigure the electrodes between the first configuration and the second configuration to control heating of the powder; anda second actuator operable to move the punch arrangement relative to the die arrangement to control compressing of the powder;wherein the first and second actuators are configured to be independently operable.

2. The tool of claim 1, wherein the die arrangement separates the punch arrangement and the electrodes.

3. The tool of claim 2, wherein the electrodes, the die arrangement and the punch arrangement are concentrically arranged.

4. The tool of any preceding claim, wherein the tool is configured to form a nanostructured powder into a micro component or a miniature component.

5. The tool of any preceding claim, wherein the first actuator is a double-acting actuator.

6. The tool of any preceding claim, wherein the second actuator is a double-acting actuator.

7. The tool of any preceding claim, wherein the second actuator comprises a high-precision linear motor.

8. The tool of any preceding claim, comprising a conductive member arranged around the die arrangement to form at least part of a current flow path between the electrodes.

59. The tool of any preceding claim, comprising a housing configured to define an operational environment of the tool.

10. A method of forming powder into a component using the tool according to any 10 preceding claim.

11. A manufacturing system comprising: a sintering station, a cooling station, and15 a die-transport arrangement comprising a rotational table configured to transfera die arrangement between the sintering station and the cooling station.

12. The manufacturing system of claim 11, wherein the sintering station comprises a tool according to any of claims 1 to 9.

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