ADDITIVE METHOD OF PRODUCTION WITH CURING

Abstract

In a process for additive manufacturing of a machine component, a hardening agent is added to a base material of a material layer in locally adjustable fashion, and the material layer is irradiated with a laser to effect local melting of the material layer such that the hardening agent is at least embedded in the base material as the material layer is irradiated with the laser.

Claims

1.-13. (canceled)

14. A process for additive manufacturing of a machine component, said process comprising the steps of: a) adding a hardening agent to a base material of a material layer in locally adjustable fashion, wherein addition of the hardening agent is adjustable to the extent that it is specifiable how much hardening agent is added to the material layer of the base material at a selectable site on a surface of the material layer; and b) irradiating the material layer with a laser to effect local melting of the material layer such that the hardening agent is at least embedded in the base material as the material layer is irradiated with the laser.

15. The process of claim 14, wherein the hardening agent is at least partially dissolved in the base material.

16. The process of claim 14, wherein a dispensing quantity of the hardening agent is locally specifiable.

17. The process of claim 14, further comprising hardening the machine component to effect a diffusion of the hardening agent in the base material.

18. The process of claim 14, wherein the hardening agent is in the form of carbon powder or carbon liquid.

19. The process of claim 14, wherein the base material is an iron-based alloy, a manganese alloy or a nickel-based alloy.

20. The process of claim 14, further comprising repeatedly performing the steps a) and b) for a plurality of material layers.

21. The process of claim 14, further comprising adjusting an intensity of the laser to initiate a diffusion of the hardening agent into the base material.

22. (canceled)

23. The process of claim 14, wherein embedding of the hardening agent in the base material brings about at least a hardening.

24. The process of claim 20, further comprising hardening the machine component through exposure to thermal energy.

25. A computer program product, comprising a control unit including a non-transitory memory storing instructions to issue commands to a dispensing apparatus for a hardening agent and to a laser for executing a process as set forth in claim 14.

26. A control unit, comprising: a processor; a memory; and a computer program product comprising a computer program stored in the memory and when loaded into the processor and executed by the processor causes the processor to control a manufacturing apparatus by performing the steps of a) adding a hardening agent to a base material of a material layer in locally adjustable fashion, wherein addition of the hardening agent is adjustable to the extent that it is specifiable how much hardening agent is added to the material layer of the base material at a selectable site on a surface of the material layer; and b) irradiating the material layer with a laser to effect local melting of the material layer such that the hardening agent is at least embedded in the base material as the material layer is irradiated with the laser.

27. A manufacturing apparatus, comprising: a dispensing apparatus for dispensing a base material; a dispensing apparatus for dispensing a hardening agent; a laser for additive manufacturing of machine components; and a control unit as set forth in claim 26.

28. A machine component, comprising: a base material joined by irradiation with a laser; a hardening agent dissolved in the base material; a first region having a first hardness; a second region adjacent to the first region and having a second hardness; and a transition from the first hardness to the second hardness in the form of a discrete step.

29. The machine component of claim 28, constructed in the form of an externally toothed gear, an internally toothed gear or a toothed rack.

Description

[0020] The invention is hereinbelow more particularly elucidated with reference to individual embodiments in figures. The figures are to be understood as supplementing each other to the extent that identical reference numerals in different figures have the same technical definition. The features of the individual embodiments may also be combined with one another. The embodiments shown in the figures may also be combined with the features outlined above. In particular:

[0021] FIG. 1 is a schematic diagram showing the construction of a manufacturing apparatus for performing an embodiment of the claimed process;

[0022] FIG. 2 is a schematic diagram showing the construction of a material layer in the course of an embodiment of the claimed process;

[0023] FIG. 3 is a schematic diagram of the sequence of an embodiment of the claimed process:

[0024] FIG. 4 is a schematic diagram of an embodiment of a claimed machine component;

[0025] FIG. 6 is a schematic view of a further embodiment of the claimed machine component.

[0026] FIG. 1 shows a schematic diagram of a construction of a manufacturing apparatus 90 with which an embodiment of the claimed process 100 may be performed. The manufacturing apparatus 90 comprises a doctor blade 32 with which a base material 30 which is substantially a metal powder may be applied in an operating region 14 in a first step 110. A hardening agent 42 is added to the base material 30 to the base material 30 with a dispensing apparatus 40 via a dispensing apparatus 40. A dispensing quantity of the hardening agent 42 may be adjusted via a dispensing nozzle 44 of the dispensing apparatus 40. The hardening agent 42 may be in the form of a carbon liquid or a carbon powder. The base material 30 and the hardening agent 42 together form a material layer 12. The dispensing apparatus 40 is movable such that a concentration of the hardening agent 42 in the plane of the material/layer 12 may be adjusted essentially arbitrarily. The totality of the material layer 12 is provided in the first step 110 of the process 100.

[0027] In a second process step 120, the material layer 12 is irradiated by a laser 20. To this end, a laser beam 25 having an adjustable intensity 26 is directed onto the material layer 12. The laser 20 effects local heating of the material layer 12, thus causing the base material 30 to melt. The laser 20 is controlled such that the irradiated material layer 12 effects further construction of a machine component 10 that is being produced. Once the laser beam 25 has passed over the material layer 12, the base material 30 solidifies and at least embeds hardening material 42. The resulting local concentration of hardening agent 42 in the molten and solidified base material 42 make it possible to adjust a hardness 72 in the machine component 10 that is being produced. In the claimed process 100, the irradiation of the material layer 12 is carried out in the second step 120. A further heat input by means of the laser 20 further makes it possible to bring about a diffusion 48 of the hardening agent 42 into the base material 30 (not shown in FIG. 1). The manufacturing apparatus 90, in particular the laser 20 and the dispensing apparatus 40, are controlled using a control unit 50 which is configured for executing commands 55. The commands 55 are generated by a computer program product 80 which is stored in the control unit 50 such that it may be executed.

[0028] FIG. 2 shows a schematic diagram of a construction of a material layer 12 such as is present during or after irradiation with a laser 20 according to a second step 120 of the claimed process 100. The material layer 12 comprises a base material 30 which is present substantially as grains 36. The hardening agent 42, which is also in the form of grains 46, is embedded in the base material 30. Thermal energy 28 introduced into the material layer 12 brings about diffusion 48 of the hardening agent 42. In FIG. 2 the hardening agent is substantially elemental carbon, which remains in the material layer 12 in the second step 120. The hardening agent 42 is incorporated into the base material 30 by the diffusion 48 and thus brings about local hardening of the base material 30. The thermal energy 28 which brings about the diffusion 48 may be supplied in the second step 120 by the laser 20 and/or in the form of process heat, for example a hardening furnace, in a third step 130. The fact that the hardening agent 42 may be applied essentially arbitrarily in the claimed process 100 means that the further diffusion distances that must be covered for a desired target state of the machine component 10 to be produced are minimized. Starting from the target state a hardening process which comprises heating and quenching may follow.

[0029] FIG. 3 shows a schematic sequence of an embodiment of the claimed process 100 with which a machine component 10 is to be produced. In a first step 110, a material layer 12 is provided. The material layer 12 comprises a base material 30 to which a hardening agent 42 is added. The hardening agent 42. Is applied to the material layer 12 using a dispensing apparatus 40. The dispensing apparatus 40 is controllable such that a dispensing quantity of the hardening agent 42 may be adjusted locally, i.e. at different positions within the plane of the material layer 12. This makes it possible to achieve essentially any desired distribution of concentrations of hardening agent 42. In a second step 120, the material layer 12 is irradiated with a laser 20 which effects local melting of the material layer 12. As a result, the hardening agent 42 is at least embedded in the base material 30. As indicated by return loop 140, the first and second steps 110, 120 are repeated until the machine component 10 that is being produced has been produced in its basic form by additive manufacturing. This is followed by a third step 130 in which the machine component 10 obtained thus far is subjected to an environment in which it is supplied with thermal energy 28, for example via a hardening furnace. This brings about diffusion 48 of the hardening agent 42 in the base material 30. This makes it possible to achieve a desired end state in the machine component 10.

[0030] An embodiment of a claimed machine component 10 is shown in FIG. 4. In particular, FIG. 4 shows an externally toothed gear 16 which is produced essentially from a plurality of material layers 12 layered on top of one another. The production of the material layers 12 is carried out with a process 100 according to any of the embodiments outlined hereinabove.

[0031] FIG. 5 shows a detailed view of a surface of a machine component 10 as shown in FIG. 4 for example. The machine component 10 comprises a first region 31 having a first hardness 35. Adjacent thereto is a second region 33 having a second hardness 37. The top of FIG. 5 further shows a diagram 70 which along the horizontal axis 71 shows a profile of the hardness 72. In the plane of the drawing. In a first region 31, the hardness 72 is essentially constant in a range of the first hardness 35. A boundary 47 marks a transition 38 of the hardness 72. The transition 38 from the range of the first hardness to the second hardness 35, 37 essentially takes the form of a step 39. The machine component 10 in FIG. 5 is produced by means of a process 100 according to one of the aforementioned embodiments. Virtually discrete spatial distributions of hardnesses 72 in the machine component 10 are achievable. The hardness 72 in the corresponding first and second regions 35, 37 is therefore selectively adaptable to constructional requirements of the machine component 10.