Diode laser fiber array for powder bed fabrication or repair
A method of forming a build in a powder bed includes emitting a plurality of laser beams from selected fibers of a diode laser fiber array onto the powder bed, the selected fibers of the array corresponding to a pattern of a layer of the build; and simultaneously melting powder in the powder bed corresponding to the pattern of the layer of the build. An apparatus for forming a build in a powder bed includes a diode laser fiber array including a plurality of diode lasers and a plurality of optical fibers corresponding to the plurality of diode lasers, each optical fiber configured to receive a laser beam from a respective diode laser and configured to emitting the laser beam; a support configured to support a powder bed or a component configured to support the powder bed at a distance from ends of the optical fibers; and a controller configured to control the diode laser fiber array to emit a plurality of laser beams from selected fibers of the diode laser fiber array onto the powder bed, the selected fibers of the array corresponding to a pattern of a layer of the build and simultaneously melt the powder in the powder bed corresponding to the pattern of the layer of the build.
1. A method of forming a build in a powder bed, comprising:
turning on selected diode lasers of a diode laser fiber array, the selected lasers of the diode laser fiber array corresponding to a desired pattern of a layer of the build;
emitting a plurality of laser beams from fibers coupled to the selected diode lasers onto the powder bed;
simultaneously melting powder in the powder bed corresponding to the desired pattern of the layer of the build; and
turning off the selected diode lasers.
2. A method according to claim 1 , further comprising:
controlling at least one of a duration of each laser beam, a pulse energy of each diode laser, a pulse width of each diode laser, an average output power of each diode laser, an energy distribution of each laser beam, power density of each laser beam, a rate of reduction of the power of each laser beam, and/or a distance of ends of the fibers from the powder bed.
3. A method according to claim 2 , wherein the average output power of each diode laser is up to about 60 W.
4. A method according to claim 2 , wherein the average output power of each diode laser is between about 2 W to about 60 W.
5. A method according to claim 2 , wherein the power density of each laser beam is about 1,000,000 W/cm 2 .
6. A method according to claim 2 , wherein the distance of ends of the fibers from the powder bed is between about 5 mm to about 150 mm.
7. A method according to claim 2 , wherein the energy distribution of each laser beam is Gaussian or a top hat.
8. A method according to claim 1 , wherein the powder is metal, ceramic, glass or plastic.
9. A method according to claim 1 , further comprising:
emitting laser beams from fibers coupled to diode lasers of the diode laser fiber array that are adjacent to the desired pattern of the layer; and
heating the powder adjacent to the powder of the layer of the build to control a cooling rate of the melted powder.
10. A method according to claim 9 , wherein heating the powder adjacent to the powder of the layer comprises heating the powder at least one of prior to and/or during and/or after simultaneous melting of the powder of the desired pattern of the layer.
11. A method according to claim 9 , wherein a power density of the laser beams heating the powder adjacent the desired pattern is in a range of from about 100 W/cm 2 to about 100,000 W/cm 2 .
12. A method according to claim 1 , wherein a thickness of each layer is between about 1 μm to about 1 mm.
13. A method according to claim 12 , wherein a thickness of each layer is about 100 μm.
14. A method according to claim 1 , wherein the build is a repair of a component.
15. A method according to claim 14 , wherein the component is a turbine component.
16. A method according to claim 15 , wherein the turbine component is an airfoil.
17. A method according to claim 1 , wherein the build is a component of a turbine.
18. A method according to claim 17 , wherein the component is an airfoil.
19. A method according to claim 1 , further comprising:
repeating the emitting and simultaneous melting to form a plurality of layers of the build.
20. A method according to claim 1 , further comprising:
allowing the melted powder to cool and solidify.
21. A method according to claim 1 , further comprising:
moving the selected diode lasers and the powder bed relative to each other; and
simultaneously controlling the selected diode lasers of the diode laser fiber array during relative movement.
22. A method of forming a build in a powder bed, comprising:
turning on selected diode lasers of a diode laser fiber array, the selected lasers of the diode laser fiber array corresponding to a desired pattern of a layer of the build;
emitting a plurality of laser beams from fibers coupled to the selected diode lasers onto the powder bed, wherein the average output power of each diode laser is between about 2 W to about 60 W, the power density of each laser beam is about 1,000,000 W/cm 2 , the distance of ends of the fibers from the powder bed is between about 5 mm to about 150 mm, the energy distribution of each laser beam is Gaussian or a top hat;
simultaneously melting powder in the powder bed corresponding to the desired pattern of the layer of the build, wherein the powder is metal, ceramic, glass or plastic;
controlling at least one of a duration of each laser beam, a pulse energy of each diode laser, a pulse width of each diode laser, an average output power of each diode laser, an energy distribution of each laser beam, power density of each laser beam, a rate of reduction of the power of each laser beam, and/or a distance of ends of the fibers from the powder bed, wherein a thickness of each layer is between about 1 μm to about 1 mm;
moving the selected selected diode lasers and the powder bed relative to each other; and
simultaneously controlling the selected diode lasers during relative movement;
turning off the selected diode lasers; and
allowing the melted powder to cool and solidify.
23. A method according to claim 22 , further comprising:
emitting laser beams from fibers coupled to diode lasers at least adjacent to the desired pattern of the layer; and
heating the powder adjacent to the powder of the desired pattern of the layer of the build to control a cooling rate of the melted powder, wherein a power density of the laser beams heating the powder adjacent the pattern is in a range of from about 100 W/cm 2 to about 100,000 W/cm 2 .
24. A method according to claim 23 , wherein heating the powder adjacent to the powder of the desired pattern of the layer comprises heating the adjacent powder at least one of prior to and/or during and/or after simultaneous melting of the powder of the pattern of the layer.
25. A method according to claim 22 , wherein a thickness of each layer is about 100 μm.
26. A method according to claim 22 , wherein the build is a repair of a component.
27. A method according to claim 26 , wherein the component is a turbine component.
28. A method according to claim 27 , wherein the turbine component is an airfoil.
29. A method according to claim 22 , wherein the build is a component of a turbine.
30. A method according to claim 29 , wherein the component is an airfoil.
31. A method according to claim 22 , further comprising:
repeating the emitting and simultaneous melting to form a plurality of layers of the build.
32. A method according to claim 1 , further comprising:
controlling each of a duration of each laser beam, a pulse energy of each diode laser, a pulse width of each diode laser, an average output power of each diode laser, an energy distribution of each laser beam, a power density of each laser beam, a rate of reduction of the power of each laser beam, and a distance of ends of the fibers from the powder bed.
33. A method according to claim 1 , wherein emitting the plurality of laser beams from the selected diode lasers of the diode laser fiber array onto the powder bed comprises emitting the plurality of laser beams for 5 to 15 milliseconds.
34. A method according to claim 1 , wherein simultaneously melting powder in the powder bed corresponding to the desired pattern of the layer of the build comprises superheating the powder bed to control a viscosity of the melted region.
35. A method according to claim 9 , further comprising:
controlling each of a duration of each laser beam, a pulse energy of each diode laser, a pulse width of each diode laser, an average output power of each diode laser, an energy distribution of each laser beam, a power density of each laser beam, a rate of reduction of the power of each laser beam, and a distance of ends of the fibers from the powder bed.
36. A method according to claim 9 , wherein emitting the plurality of laser beams from the selected diode lasers of the diode laser fiber array onto the powder bed comprises emitting the plurality of laser beams for 5 to 15 milliseconds.
37. A method according to claim 9 , wherein simultaneously melting powder in the powder bed corresponding to the desired pattern of the layer of the build comprises superheating the powder bed to control a viscosity of the melted region.