SYSTEM AND METHOD FOR CONTROLLING THE INPUT ENERGY FROM AN ENERGY POINT SOURCE DURING METAL PROCESSING

• US 20160151859A1
• Filed: 12/02/2014
• Published: 06/02/2016
• Est. Priority Date: 12/02/2014
• Status: Active Grant

• Current Assignee: Product Innovation and Engineering LLC
• Original Assignee: Product Innovation and Engineering LLC
• Inventors: Sparks, Todd Eugene
• Granted Patent: US 10,632,566 B2
• Time in Patent Office: Days
• CPC Class Codes: B22F 10/22 Direct deposition of molten metal
• CPC Class Codes: B22F 10/25 Direct deposition of metal particles, e.g. direct metal deposition [DMD] or laser engineered net shaping [LENS]
• CPC Class Codes: B22F 10/36 of energy beam parameters
• CPC Class Codes: B22F 12/90 Means for process control, e.g. cameras or sensors
• CPC Class Codes: B22F 2203/03 for feed-back
• CPC Class Codes: B22F 2203/11 temperature, temperature profile
• CPC Class Codes: B22F 2999/00 Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B23K 26/034 Observing the temperature of the workpiece
• CPC Class Codes: B23K 26/34 Laser welding for purposes other than joining
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

A method for controlling, during metal processing, the input energy from an energy point source that directs focused emitted energy onto a metal workpiece having a geometry, wherein the directed focused emitted energy creates a melt pool and hot zone on the workpiece that emit radiation during the process. The method comprises determining a wavelength range for the emitted radiation that is within a spectral range of radiation emitted by the hot zone during processing that is comparatively high in amount in relation to the amount of radiation emitted by the melt pool in that spectral range during processing; directing the beam onto the workpiece to generate a melt pool and hot zone on the structure; measuring the intensity of radiation within the determined wavelength range; and adjusting the input energy from the energy point source based upon the measured intensity of radiation within the determined wavelength range.

Claims

1. A method for controlling, during metal processing, the input energy from an energy point source that inputs focused emitted energy into a metal workpiece and forms a melt pool, hot zone and bulk area, the method comprising:

a) determining one or more wavelengths of radiation that will be emitted by the hot zone during processing in an amount that will be comparatively higher than the amount of radiation in those same one or more wavelengths emitted by either the melt pool or bulk structure during processing;

b) selecting a wavelength range of radiation for detection and measurement, the selected wavelength range including the one or more wavelengths of radiation determined to be emitted by the hot zone during processing in an amount comparatively higher than that emitted by the melt pool or bulk structure;

c) inputting focused emitted energy from the energy point source into the workpiece to generate a melt pool and hot zone on the workpiece;

d) measuring the intensity of radiation within the selected range of radiation; and

e) adjusting the input energy from the energy point source based upon the measured intensity of radiation within the selected wavelength range.

2. The method of claim 1 further including prior to step “

d”

filtering the radiation from the workpiece to block radiation outside the selected wavelength range from being measured.

3. A method for controlling, during metal processing, the input energy from an energy point source that inputs focused emitted energy into a metal workpiece, the method comprising:

a) inputting focused emitted energy from the energy point source into the workpiece to generate a melt pool and hot zone on the workpiece;

b) measuring the intensity of radiation within a determined wavelength range, the determined wavelength range being within a spectral range of radiation emitted by the hot zone during processing that is comparatively high in amount in relation to the amount of radiation emitted by the melt pool in that spectral range during processing; and

c) adjusting the input energy from the energy point source based upon the measured intensity of radiation within the determined wavelength range.

4. The method of claim 3 further including prior to step “

b”

filtering the radiation from the workpiece to block radiation outside the determined wavelength range from being measured.

5. A method for controlling, during metal processing, the input energy from an energy point source that inputs focused emitted energy into a metal workpiece, wherein the input energy creates a melt pool and hot zone on the workpiece, the melt pool and hot zone each emitting radiation during the process, the method comprising:

a) determining a wavelength range correlating to a spectral range of radiation emitted by the hot zone during processing that is comparatively high in relation to the radiation emitted by the melt pool in that spectral range during processing;

b) inputting the energy into the workpiece to generate a melt pool and hot zone on the structure;

c) measuring the intensity of radiation within the determined wavelength range; and

d) adjusting the input energy from the energy point source based upon the measured intensity of radiation within the determined wavelength range.

6. The method of claim 5 further including prior to step “

c”

filtering the radiation from the workpiece to block radiation outside the determined wavelength range from being measured.

7. A method of forming a build on a substrate by an additive layering process, the build having a geometry and the additive layering process involving introducing an additive material into a beam produced by an energy point source, the method comprising:

a) using the beam to generate a melt pool and hot zone on the substrate;

b) feeding the additive material into the melt pool;

c) measuring the intensity of radiation emitted by the workpiece during processing within a determined wavelength range, the determined wavelength range being within a spectral range of radiation emitted by the hot zone during processing that is comparatively high in amount in relation to the amount of radiation emitted by the melt pool in that spectral range during processing; and

d) adjusting the beam based upon the measured intensity of radiation emitted by the hot zone within the specific wavelength range.

8. The method of claim 7 further including prior to step “

c”

filtering the radiation from the workpiece to block radiation outside the determined wavelength range from being measured.

9. The method of claim 8 further including:

prior to step a);

creating a geometric description representing the geometry of the build during the additive layering; and

creating a path description that represents the path of the energy point source through space during the additive layering; and

.

using during the additive layering process the geometric description and path description as inputs in conjunction with the measured intensity of the radiation to adjust the beam.

10. A method of forming a build on a workpiece by an additive layering process using a beam directed by an energy point source onto the substrate wherein the directed beam creates a melt pool and hot zone on the workpiece that emit radiation during the process, the method comprising:

a) determining a wavelength range correlating to a spectral range of radiation emitted by the hot zone during processing that is comparatively high in relation to the radiation emitted by the melt pool in that spectral range during processing;

a) directing the beam onto the workpiece to generate a melt pool and hot zone on the structure;

b) feeding stock material into the melt pool;

c) measuring the intensity of radiation within the determined wavelength range; and

d) adjusting the beam based upon the measured intensity of radiation within the determined wavelength range.

11. The method of claim 10 further including prior to step “

c”

filtering the radiation from the workpiece to block radiation outside the determined wavelength range from being measured.

12. A system for processing a metal workpiece, the system comprising:

a) an energy point source configured to input focused emitted energy into the workpiece, the focused emitted energy when applied to the workpiece creating a melt pool and hot zone on the workpiece;

b) a sensor adapted to receive and measure intensity of radiation within a specific wavelength range, the determined wavelength range being within a spectral range of radiation emitted by the hot zone during processing that is comparatively high in amount in relation to the amount of radiation emitted by the melt pool in that spectral range during processing; and

c) a controller configured to receive the electric signal output by the sensor and adjust the input energy from the energy point source based upon the electric signal received from the sensor.

13. The system of claim 12 further including:

one or more lenses to focus the radiation onto the sensor; and

one or more filters to filter out radiation outside the specific wavelength range and prevent it from being received by the sensor.

14. The system of claim 13 wherein the sensor, the one or more filters and the one or more lenses are unitarily housed within a sensor-optics unit.

15. The system of claim 13 further including a support to hold the substrate and move the substrate relative to the energy point source.

16. An additive layering system for forming a build on a substrate, the system comprising:

a) an energy point source configured to direct a beam upon the substrate, the beam when applied to the substrate creating a melt pool and hot zone on the substrate;

c) the energy point source being further configured to heat a stock material fed into the melt pool such that the stock material is deposited upon the substrate and forms the build;

d) a sensor adapted to receive and measure intensity of radiation within a specific wavelength range, the determined wavelength range being within a spectral range of radiation emitted by the hot zone during processing that is comparatively high in amount in relation to the amount of radiation emitted by the melt pool in that spectral range during processing; and

e) a controller configured to receive the electric signal output by the sensor and adjust the beam based upon the electric signal received from the sensor.

17. The system of claim 16 further including:

one or more lenses to focus the radiation onto the sensor; and

one or more filters to filter out radiation outside the specific wavelength range and prevent it from being received by the sensor.

18. The system of claim 17 wherein the sensor, the one or more filters and the one or more lenses are unitarily housed within a sensor-optics unit.

19. The system of claim 18 further including a support to hold the substrate and move the substrate relative to the energy point source.