Apparatuses, systems and methods for three-dimensional printing
The present disclosure provides three-dimensional (3D) objects, 3D printing processes, as well as methods, apparatuses and systems for the production of a 3D object. Methods, apparatuses and systems of the present disclosure may reduce or eliminate the need for auxiliary supports. The present disclosure provides three dimensional (3D) objects printed utilizing the printing processes, methods, apparatuses and systems described herein.
1. A method for generating a three-dimensional object, comprising:
(a) providing (i) a first layer of powder material in an enclosure at a first time (t 1 ) and (ii) a second layer of powder material in the enclosure at a second time (t 2 ) that follows t 1 , wherein the second layer of powder material is provided adjacent to the first layer of powder material, wherein the first layer of powder material and second layer of powder material form a powder bed, and wherein the powder material comprises an elemental metal, metal alloy, ceramic, or an allotrope of elemental carbon;
(b) transforming at least a portion of the powder material in the second layer to form a transformed material; and
(c) using a heat sink adjacent to the first layer or the second layer to remove thermal energy from the second layer at a time interval from t 2 to a third time (t 3 ), wherein the thermal energy is removed along a direction above the powder bed, and wherein upon removal of thermal energy, the transformed material solidifies to form at least a portion of the three-dimensional object.
2. The method of claim 1 , wherein during the time interval from t 2 to t 3 , an average temperature at a point in the second layer is maintained at less than or equal to about 250° C.
3. The method of claim 2 , wherein during the time interval from t 2 to t 3 , the average temperature is maintained at less than or equal to about 100° C.
4. The method of claim 1 , wherein in (b), the transforming is with the aid of an energy beam having a first energy per unit area (S 1 ), and wherein in (c), during the time interval from t 2 to t 3 thermal energy is removed at a second energy per unit area (S 2 ) that is at least about 0.3 times S 1 .
5. The method of claim 4 , wherein the second energy per unit area (S 2 ) is at least about 0.5 times S 1 .
6. The method of claim 1 , wherein the thermal energy is removed from a top surface of the powder bed.
7. The method of claim 1 , wherein the transforming comprises fusing individual particles of the powder material.
8. The method of claim 7 , wherein fusing comprises melting or sintering the individual particles.
9. The method of claim 1 , wherein at t 3 , a third layer of powder material is provided adjacent to the second layer of powder material.
10. The method of claim 1 , wherein the transforming comprises directing an energy beam to at least a portion of the second layer.
11. A system for generating a three-dimensional object, comprising:
an enclosure that accepts a first layer of powder material at a first time (t 1 ) and a second layer of powder material at a second time (t 2 ) that follows t 1 to form a powder bed, wherein the second layer of powder material is adjacent to the first layer of powder material, and wherein the powder material comprises an elemental metal, metal alloy, ceramic, or an allotrope of elemental carbon;
a heat sink adjacent to the first layer or the second layer, wherein the heat sink removes thermal energy from the second layer; and
a controller operatively coupled to the heat sink and programmed to (i) transform at least a portion of the powder material in the second layer to form a transformed material, and (ii) use the heat sink to remove thermal energy from the second layer at a time interval from t 2 to a third time (t 3 ), wherein the thermal energy is removed along a direction above the powder bed, and wherein upon removal of thermal energy, the transformed material solidifies to form at least a portion of the three-dimensional object.
12. The system of claim 11 , further comprising an energy source that provides an energy beam to at least a portion of the second layer.
13. The system of claim 12 , wherein the controller is operatively coupled to the energy source and programmed to direct the energy beam to at least the portion of the second layer.
14. The system of claim 12 , wherein the heat sink is movable to or from a position that is between the energy source and the powder bed.
15. The system of claim 11 , wherein the controller is programmed to (1) transform at least a portion of the powder material in the second layer to form a transformed material using an energy beam having a first energy per unit area (S 1 ), and (2) use the heat sink to remove thermal energy during the time interval from t 2 to t 3 at a second energy per unit area (S 2 ) that is at least about 0.3 times S 1 .
16. The system of claim 15 , wherein the second energy per unit area (S 2 ) is at least about 0.5 times S 1 .
17. The system of claim 11 , wherein the controller is programmed to use the heat sink to remove the thermal energy from a top surface of the powder bed.
18. The system of claim 11 , wherein the controller is programmed to control an average temperature of the second layer of powder material.
19. The system of claim 18 , wherein during the time interval from t 2 to t 3 , the controller is programmed to maintain an average temperature at a point in the second layer at less than or equal to about 250° C.
20. The system of claim 19 , wherein during the time interval from t 2 to t 3 , the controller is programmed to maintain the average temperature at less than or equal to about 100° C.
21. The system of claim 11 , wherein the heat sink is movable.
22. The system of claim 21 , wherein the controller is programmed to move the heat sink.
23. The system of claim 11 , wherein heat sink is separated from the powder bed by a gap.
24. The system of claim 23 , wherein the gap is at a spacing of less than or equal to about 50 millimeters.
25. The system of claim 23 , wherein the gap is at an adjustable spacing between the heat sink and the powder bed.
26. The system of claim 25 , wherein the controller is programmed to regulate the adjustable spacing.
27. The system of claim 11 , wherein the heat sink comprises a material having a thermal conductivity of at least about 20 Watts per meter per degree Kelvin (W/mK).
28. The system of claim 11 , wherein the heat sink further comprises a cleaning member that removes the powder material or debris from a surface of the heat sink.
29. The system of claim 11 , further comprising a collection member that collects a remainder of the powder material or debris from the heat sink or the powder bed.
30. The system of claim 11 , wherein the heat sink comprises one or more openings.