Method and device for controlling an irradiation system
In a method for controlling an irradiation system ( 20 ) for use in an apparatus ( 10 ) for producing a three-dimensional work piece and comprising a first and a second irradiation unit ( 22 a, 22 b ) a first irradiation area ( 18 a ) is defined on a surface of a carrier ( 16 ) adapted to receive a layer of raw material powder. A layer of raw material powder applied onto the carrier ( 16 ) in the first irradiation area ( 18 a ) is irradiated by the first irradiation unit ( 22 a ) of the irradiation system ( 20 ), wherein the operation of the first irradiation unit ( 22 a ) is controlled in such a manner that the raw material powder is pre-heated. Thereafter the layer of raw material powder applied onto the carrier ( 16 ) in the first irradiation area ( 18 a ) is irradiated by means of the second irradiation unit ( 22 b ) of the irradiation system ( 20 ), wherein the operation of the second irradiation unit ( 22 b ) is controlled in such a manner that the raw material powder is heated to a temperature which allows sintering and/or melting of the raw material powder in order to generate a layer of the three-dimensional work piece.
1. Method for controlling an irradiation system for use in an apparatus for producing a three-dimensional work piece and comprising a first and a second irradiation unit, the method comprising the steps of:
defining a first irradiation area on a surface of a carrier adapted to receive a layer of raw material powder,
irradiating a layer of raw material powder applied onto the carrier in the first irradiation area by the first irradiation unit of the irradiation system, wherein the operation of the first irradiation unit is controlled in such a manner that the raw material powder is pre-heated, and
thereafter irradiating the layer of raw material powder applied onto the carrier in the first irradiation area by means of the second irradiation unit of the irradiation system, wherein the operation of the second irradiation unit is controlled in such a manner that the raw material powder is heated to a temperature which allows sintering and/or melting of the raw material powder in order to generate a layer of the three-dimensional work piece.
2. The method according to claim 1 ,
wherein the operation of the first and/or the second irradiation unit is controlled by appropriately controlling an output power, a radiation beam size, a radiation pattern according to which a radiation beam is guided over the raw material powder applied onto the carrier and/or a scan speed at which a radiation beam is guided over the raw material powder applied onto the carrier for the first and/or the second irradiation unit and/or by selecting an output radiation wavelength for the first and/or the second irradiation unit.
3. The method according to claim 1 ,
wherein the first irradiation unit emits an electron beam and/or a plurality of radiation beams, and/or wherein the second irradiation unit emits a laser beam.
4. The method according to claim 1 ,
wherein the operation of the first and/or the second irradiation unit is controlled in dependence on temperature signals indicative of the temperature of the raw material powder during being irradiated by first and/or the second irradiation unit, the temperature signals in particular being provided by a pyrometer and/or a thermal imaging camera.
5. The method according to claim 1 ,
further comprising the steps of:
defining a second irradiation area on the surface of the carrier, and
irradiating a layer of raw material powder applied onto the carrier in the second irradiation area by the second irradiation unit of the irradiation system, while the first irradiation unit irradiates a layer of raw material powder applied onto the carrier in the first irradiation area, and/or
irradiating a layer of raw material powder applied onto the carrier in the first irradiation area by the second irradiation unit of the irradiation system, while the first irradiation unit irradiates a layer of raw material powder applied onto the carrier in the second irradiation area.
6. The method according to claim 1 ,
wherein the irradiation system, the first irradiation unit and/or the second irradiation unit is/are moved relative to the carrier in order to allow the first and/or the second irradiation area to be irradiated by the first and the second irradiation unit in a successive manner, and/or wherein the carrier and/or a process chamber accommodating the carrier is/are moved relative to the irradiation system, the first irradiation unit and/or the second irradiation unit in order to allow the first and/or the second irradiation area to be irradiated by the first and the second irradiation unit in a successive manner.
7. The method according to claim 6 ,
wherein the irradiation system, the first irradiation unit and/or the second irradiation unit is/are rotated relative to the carrier about 180°, and/or wherein the carrier and/or the process chamber accommodating the carrier is/are rotated relative to the irradiation system, the first irradiation unit and/or the second irradiation unit about 180°, in order to allow the first and/or the second irradiation area to be irradiated by the first and the second irradiation unit in a successive manner.
8. Device for controlling an irradiation system for use in an apparatus for producing a three-dimensional work piece and comprising a first and a second irradiation unit, the device comprising:
a definition unit adapted to define a first irradiation area on a surface of a carrier adapted to receive a layer of raw material powder, and
a control unit which is adapted to control the operation of the first irradiation unit in such a manner that a layer of raw material powder applied onto the carrier in the first irradiation area is irradiated by the first irradiation unit so as to pre-heat the raw material powder, and which further is adapted to control the operation of the second irradiation unit in such a manner that the layer of raw material powder applied onto the carrier in the first irradiation area thereafter is irradiated by the second irradiation unit so as to heat the raw material powder to a temperature which allows sintering and/or melting of the raw material powder in order to generate a layer of the three-dimensional work piece.
9. The device according to claim 8 ,
wherein the control unit is adapted to control the operation of the first and/or the second irradiation unit by appropriately controlling an output power, a radiation beam size, a radiation pattern according to which a radiation beam is guided over the raw material powder applied onto the carrier and/or a scan speed at which a radiation beam is guided over the raw material powder applied onto the carrier for the first and/or the second irradiation unit and/or wherein the an output radiation wavelength is appropriately selected for the first and/or the second irradiation unit so as to control the operation of the first and/or the second irradiation unit.
10. The device according to claim 8 ,
wherein the first irradiation unit is adapted to emit an electron beam and/or a plurality of radiation beams, and/or wherein the second irradiation unit is adapted to emit a laser beam.
11. The device according to claim 8 ,
wherein the control unit is adapted to control the operation of the first and/or the second irradiation unit in dependence on temperature signals indicative of the temperature of the raw material powder during being irradiated by the first and/or the second irradiation unit, the temperature signals in particular being provided by a pyrometer and/or a thermal imaging camera.
12. The device according to claim 8 ,
wherein the definition unit is adapted to define a second irradiation area on the surface of the carrier, and wherein the control unit is adapted to control the operation of the first and/or the second irradiation unit in such a manner that a layer of raw material powder applied onto the carrier in the second irradiation area is irradiated by the second irradiation unit of the irradiation system, while the first irradiation unit irradiates a layer of raw material powder applied onto the carrier in the first irradiation area, and/or wherein the control unit is adapted to control the operation of the first and/or the second irradiation unit in such a manner that a layer of raw material powder applied onto the carrier in the first irradiation area is irradiated by the second irradiation unit of the irradiation system, while the first irradiation unit irradiates a layer of raw material powder applied onto the carrier in the second irradiation area.
13. The device according to claim 8 ,
wherein the irradiation system, the first irradiation unit and/or the second irradiation unit is/are movable relative to the carrier in order to allow the first and/or the second irradiation area to be irradiated by the first and the second irradiation unit in a successive manner, and/or wherein the carrier and/or a process chamber accommodating the carrier is/are movable relative to the irradiation system, the first irradiation unit and/or the second irradiation unit in order to allow the first and/or the second irradiation area to be irradiated by the first and the second irradiation unit in a successive manner.
14. The device according to claim 13 ,
wherein the irradiation system, the first irradiation unit and/or the second irradiation unit is/are rotatable relative to the carrier about 180°, and or wherein the carrier and/or the process chamber accommodating the carrier is/are rotatable relative to the irradiation system, the first irradiation unit and/or the second irradiation unit about 180°, in order to allow the first and/or the second irradiation area to be irradiated by the first and the second irradiation unit in a successive manner.
15. Apparatus for producing a three-dimensional work piece, comprising:
an irradiation system comprising a first and a second irradiation unit and
a device for controlling the irradiation system according to claim 8 .