METHOD AND DEVICE FOR THE GENERATIVE PRODUCTION OF A THREE-DIMENSIONAL COMPONENT

Abstract

A method for the generative production of a three-dimensional component includes providing a metallic starting material in the form of a powder bed in a substantially horizontal starting plane, supplying a process gas to the starting material, melting the starting material by a heat source, repeating the above steps, wherein at least a portion of the process gas is supplied through the powder bed. A related device is also provided.

Claims

1. A method for the generative production of a three-dimensional component comprising: (a) providing a metallic starting material as a powder bed in a substantially horizontal starting plane; (b) supplying a process gas to the starting material, wherein at least a portion of the process gas is supplied through the powder bed and said process gas is a gas selected from the group consisting of helium, hydrogen, and a mixture thereof; (c) melting the starting material by means of a heat source; (d) cooling and solidifying the starting material; and (e) repeating steps (a)-(d) above.

2-13. (canceled)

14. The method of claim 1, wherein the supplying the process gas comprises applying the process gas from a distribution device to the powder bed in an area where the three-dimensional component is produced.

15. The method of claim 1, further comprising flowing the process gas substantially vertically to the horizontal starting plane in the direction of the three-dimensional component.

16. The method of claim 1, further comprising tempering the process gas before said process gas enters a process chamber in which the three-dimensional component is produced.

17. The method of claim 1, further comprising controlling a heat balance of the process gas by tempering said process gas, said tempering comprising a select one of heating the process gas, and cooling the process gas.

18. A device for the generative production of a component comprising: a process chamber having a chamber wall for closing said process chamber from an exterior of the chamber wall; a process gas supply device containing a process gas selected from the group consisting of helium, hydrogen, and a mixture thereof; a horizontally arranged construction platform for accommodating starting material provided in a powder bed form, the construction platform comprising a distribution device including a plurality of gas supply openings for applying the process gas from the process gas supply device to at least a portion of the powder bed; a storage container for accommodating the starting material, the starting material being solidifiable; an application device for applying the starting material to the construction platform; and a laser for generating a laser beam to the starting material.

19. The device of claim 18, wherein the plurality of the gas supply openings each are substantially vertical with respect to a direction of the component.

20. The device of claim 18, wherein the distribution device forms the plurality of gas supply openings and is selected from the group consisting of a screen, a membrane-like structure, a perforated film, a sintered body, and a nozzle plate.

21. The device of claim 18, further comprising a tempering device including a tempering chamber for tempering the process gas.

22. The device of claim 21, wherein the tempering chamber comprises at least one nozzle for injecting a heat transfer medium to the process gas, the heat transfer medium selected from the group consisting of a cooling medium, and a cryogenic medium; and the device further comprises a storage container for the heat transfer medium.

23. The device of claim 21, wherein the tempering device comprises a heat transfer device for selectively cooling and heating the process gas, the heat transfer device constructed and arranged for heat transfer selected from the group consisting of direct heat transfer, indirect heat transfer, and semi-indirect heat transfer.

24. The device of claim 18, wherein the distribution device comprises a distribution tempering device being integral with the distribution device and having at least one of cooling channels, and heating elements.

25. The device of claim 21, further comprising a control device for controlling the tempering device, the control device comprising a temperature control device including a closed control loop which controls the temperature of the process gas.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The invention will be explained in more detail below by means of a FIGURE.

[0062] The FIGURE shows a schematic illustration of a device according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0063] A device 1 for the generative production of a three-dimensional component will be described below. As already mentioned above, every device is on principle suitable for the generative production of three-dimensional components for carrying out the method according to the invention.

[0064] The device is a laser melting device 1. The laser melting device 1 comprises a process chamber 2, which is closed to the outside by means of a chamber wall 3 and which defines a processing room 4. The processing chamber 2 serves as assembly space for the three-dimensional component.

[0065] A container 13, which is open to the top, is arranged in the processing chamber 2. A construction platform 5 for accommodating the component 6 to be produced is arranged in the container 13. The construction platform 5 has a height-adjusting device (not illustrated), by means of which the construction platform 5 can be adjusted in vertical direction in such a way that a surface of a layer, which is to be solidified anew, is located in a working plane.

[0066] The construction platform 5 is embodied as a distribution device 14, which has a plurality of gas supply openings 16, for applying process gas to at least a partial area of the powder bed.

[0067] The gas supply openings 16 run substantially vertically to the starting plane in the direction of the component.

[0068] The distribution device 14 can be a screen, a membrane-like structure, a perforated film, a sintered body or a nozzle plate.

[0069] The device 1 furthermore comprises a storage container 7. The storage container 7 is embodied for accommodating a solidifiable starting material in powder form.

[0070] In addition, provision is made for an application device 8 for applying the starting material to the construction platform 5. Such an application device 8 can be moved parallel to the working plane in horizontal direction.

[0071] A laser 9 for generating a laser beam or a heat source, respectively, is arranged in the processing chamber 2. A laser beam generated by the laser 9 is deflected via a deflecting device 10 and is focused onto a predetermined point directly underneath the working plane by means of a focusing device (not illustrated). The course of the laser beam can be changed in such a manner by means of the deflecting device 10 that it fuses the spots of the applied layer, which correspond to the cross section of the object to be produced.

[0072] In addition, provision is made for a process gas supply device 11, by means of which a process gas can be applied to the processing chamber 2.

[0073] The process gas supply device 11 has a storage container for the process gas, wherein the process gas storage container (not illustrated) is connected to the distribution device 14 via a line section. In the alternative, the process gas storage container can be connected to the distribution device 14 and can be directly connected to the processing chamber via an inlet.

[0074] Provision is furthermore made for a tempering device 12.

[0075] The tempering device 12 for tempering the process gas is preferably integrated in this line section.

[0076] According to a first exemplary embodiment, the tempering device 12 has a heat transfer device or a heat exchanger device, respectively, by means of which the process gas can be tempered, before it enters the processing chamber.

[0077] According to a further exemplary embodiment, the tempering device 12 has a tempering chamber. Provision is made in the tempering chamber for at least one nozzle, which is connected to a storage container for a cryogenic medium in order to inject cryogenic medium into the tempering chamber in such a way that the process gas is cooled.

[0078] Cryogenic medium can thus be supplied to the tempering chamber via the nozzle. The process gas and thus the component to be produced in the processing chamber, can thus be cooled in this manner.

[0079] The tempering device 12 an also be embodied as a heat exchanger device.

[0080] Provision can furthermore be made in addition to or as an alternative for the above-described tempering device 12 for the distribution tempering device 15, which comprises cooling channels or heating elements, so that the distribution tempering device 15 is an integral part of the distribution device.

[0081] Provision can also be made for two tempering devices 12, so that an external tempering device (arranged outside of the processing chamber) and a tempering device is an integral part of the distribution device 14.

[0082] The tempering device 12 furthermore comprises a control device (not illustrated) for controlling the tempering device. The control device can comprise a temperature control device (not illustrated) comprising a closed control loop, which controls the temperature. The temperature control device can comprise a P-controller, an I-controller, a D-controller and combinations thereof, such as, e.g., a PID-controller. By means of at least one temperature sensor, the temperature control device captures an actual value of a temperature of the process gas and/or of the process gas atmosphere and/or of the component 6 and compares it to a predetermined setpoint value, wherein the predetermined setpoint value is adjusted via an actuator.

[0083] A method according to the invention will be described below by means of a first exemplary embodiment.

[0084] In the first step, a metallic starting material is thereby applied or provided, respectively, on the construction platform in the form of a powder bed by means of the coating device. In the alternative, the metallic starting material can also be supplied by means of a powder feeder or a wire feeder.

[0085] In a second step, the process gas is subsequently supplied to the tempering chamber of the tempering device from a process gas storage container.

[0086] In a next step, the process gas in then supplied to the powder bed or the processing chamber, respectively, via the distribution device. With regard to this, reference is made to the above-described advantages.

[0087] In a next step, the starting material is fused by means of the laser.

[0088] These steps are repeated.

[0089] The tempering is controlled by a control or temperature control device, respectively, wherein an actual value of a temperature of the process gas and/or of the process gas atmosphere and/or of the component is captured by means of at least one temperature sensor, is compared to a predetermined setpoint value and the predetermined setpoint value is adjusted via an actuator.

[0090] To reach the setpoint value, a cryogenic medium from a storage container for cryogenic medium is injected into the tempering chamber in an intermediate step as needed, and the process gas is cooled down in this manner.

[0091] The cooled process gas is then supplied to the processing chamber. The temperature of the component to be produced can be influenced by supplying the cooled process gas.

[0092] The temperature of the component can be optimally adjusted in this manner.

[0093] These steps are repeated until the component is completed.

[0094] Due to the fact that the metal powder contains fewer contaminations due to the locally limited application with process gas, components of higher quality and with less post-processing can be produced.

[0095] In addition, provision can be made for a stabilizing step, in which the layer is cooled down and solidified. For the most part, the solidification already takes place during the process at another location in the assembly space or when the next powder layer is applied.