Method for additive manufacturing of turbomachine components

1. A method for fabricating a turbomachine component comprising a metal alloy, the method comprising:

combining two or more elemental powders to form a powdered material;

forming a first metal alloy layer of the turbomachine component on a substrate, wherein forming the first metal alloy layer comprises:

melting a first portion of the powdered material to a first molten material with a heat source;

mixing the first molten material with the heat source; and

cooling the first molten material to form the first metal alloy layer,

wherein mixing the first molten material with the heat source comprises directing an energy beam of the heat source along a first portion of the powdered material in a substantially circular path and/or radially oscillating the energy beam;

forming a second metal alloy layer of the turbomachine component on the first metal alloy layer; and

binding the first metal alloy layer with the second metal alloy layer to fabricate the turbomachine component.

2. The method of claim 1 , wherein forming the second metal alloy layer comprises:

melting a second portion of the powdered material to a second molten material with the heat source;

mixing the second molten material with the heat source; and

cooling the second molten material to form the second metal alloy layer.

3. The method of claim 1 , wherein combining the two or more elemental powders with one another to form the powdered material comprises homogenously mixing the two or more elemental powders.

4. The method of claim 3 , wherein the two or more elemental powders are mixed in proportions substantially equal to a stoichiometric composition of the metal alloy of the turbomachine component.

5. The method of claim 1 , further comprising shaping at least one of the two or more elemental powders to provide the at least one of the two or more elemental powders with uniform shapes.

6. The method of claim 1 , further comprising sizing at least one of the two or more elemental powders to reduce particle sizes of the at least one of the two or more elemental powders.

7. The method of claim 1 , wherein mixing the first molten material with the heat source further comprises oscillating the energy beam along at least a portion of a radial length of the substantially circular path while concurrently directing the energy beam along the substantially circular path.

8. The method of claim 1 , wherein the turbomachine component is a rotor and the method comprises:

fabricating a first section of the rotor with a layering device, the first section including a first impeller integrally formed with a first portion of a rotary shaft;

where fabricating the first section with the layering device comprises:

generating a digital model of the first section of the rotor with a computer aided design assembly;

partitioning the digital model into at least a first digital cross-section and a second digital cross-section;

forming the first metal alloy layer of the first section on a substrate

using the first digital cross-section as a template, wherein forming the first metal alloy layer of the first section comprises:

melting the first portion of the powdered material to the first molten material with a laser as heat source:

mixing the first molten material with the laser; and

cooling the first molten material to form the first metal alloy layer;

forming the second metal alloy layer of the first section on the first metal alloy layer; and

binding the first metal alloy layer with the second metal alloy layer to fabricate the first section of the rotor;

fabricating a second section of the rotor with the layering device, the second section including a second impeller integrally formed with a second portion of the rotary shaft; and

coupling the first section with the second section to fabricate the rotor of the turbomachine.

9. The method of claim 8 , wherein coupling the first section with the second section to fabricate the rotor of the turbomachine comprises metallurgically bonding the first section with the second section.

10. The method of claim 8 , wherein coupling the first section with the second section to fabricate the rotor of the turbomachine comprises coupling the first section with the second section with a mechanical fastener.

11. The method of claim 1 , wherein forming the first metal alloy layer comprises:

melting the first portion of the powdered material to the first molten material with a heat source;

mixing the first molten material with the heat source; and

cooling the first molten material to form the first metal alloy layer.

12. The method of claim 1 , wherein each of the first metal alloy layer and the second metal alloy layer comprises a nickel-based superalloy.

13. The method of claim 1 , wherein the powdered material comprises a lubricant selected from the group consisting of stearic acid, stearin, metallic stearates, and combinations thereof.

14. The method of claim 1 , wherein at least one of the first metal alloy layer and the second metal alloy layer is a cobalt-based superalloy or a nickel-based superalloy.