	US 12,257,627 B2
	Powder bed fusion additive manufacturing with load balancing for multiple beams
Jan Lukas Matyssek, Lübeck (DE)
Assigned to Nikon SLM Solutions AG, Lübeck (DE)
Filed by Nikon SLM Solutions AG, Lübeck (DE)
Filed on Oct. 18, 2023, as Appl. No. 18/489,164.
Application 18/489,164 is a continuation of application No. PCT/EP2022/059930, filed on Apr. 13, 2022.
Claims priority of application No. 10 2021 110 091.7 (DE), filed on Apr. 21, 2021.
Prior Publication US 2024/0246150 A1, Jul. 25, 2024
Int. Cl. B22F 10/85 (2021.01); B22F 10/28 (2021.01); B29C 64/153 (2017.01); B29C 64/282 (2017.01); B29C 64/371 (2017.01); B29C 64/393 (2017.01); B33Y 50/02 (2015.01); B33Y 10/00 (2015.01); B33Y 30/00 (2015.01)

CPC B22F 10/85 (2021.01) [B22F 10/28 (2021.01); B29C 64/153 (2017.08); B29C 64/282 (2017.08); B29C 64/371 (2017.08); B29C 64/393 (2017.08); B33Y 50/02 (2014.12); B33Y 10/00 (2014.12); B33Y 30/00 (2014.12)]

21 Claims

1. A method for manufacturing a workpiece, the method comprising:

fusing an area (A) of a layer of a fusible material by irradiating the surface of the area (A) of the layer using a number n, n ≥2 of at least two beam sources to project a corresponding number of n beam spots on n sets of locations (L_i) of said surface area (A) of the layer, wherein

each beam source has a predefined fuse rate (R_i) and a field of view (F_i),

and

an index i the predefined fuse rate, and the field of view corresponds to a respective i^thbeam source, 0<i ≥n, an index j, the predefined fuse rate, and the field of view corresponds to a respective j^thbeam source, 0<j≤n, and a set of all beam source indicating indices is I={1, . . . , n};

wherein the method further comprises at least the following steps:

1.1. estimating an optimum fusing time t_o(i) and/or a size of an optimum fusing area |L_i^opt|, for the area (A) at least for a first beam source represented by a first index i=1,

1.2. determining intersecting sets (IS_i) of the surface area (A) and fields of view (F_i) for at least the first index i=1 by assigning IS_i:=A∩F_iat least for i=1;

1.3. comparing a size of the intersecting sets (|IS_i|) to a product of the optimum fusing time t_o(i) with the predefined fuse rate R_iof the corresponding i^th-beam source and/or to an optimum size of the fusing area |L_i^opt| and, in response to at least one of relations t₀(i)·R_i<|IS_i| and |L_i^opt|<|IS_i| holding true, performing the following steps:

1.3.1. determining a subtrahend surface S_iwith S_i⊂IS_iand at least one of (1−α_i)(|IS_i|−t_o(i)·R_i)≤|S_i|≤(1+α_i)(|IS_i|−t_o(i)·R_i), and (1−α_i)(|IS_i|−|L_i^opt|)≤|S_i|≤(1+α_i)(|IS_i|−|L_i^opt|), wherein α_i∈{0.25, 0.2, 0.15, 0.1, 0.05, 0.025, 0.01,0.005,0} under the condition that for each p_i∈S_i, ∃F_k|p_i∈F_k, wherein k is an index such that k >i, p_iis a point of the subtrahend surface S_iand

1.3.2. assigning L_i:=IS_i−S_i, and

1.4. in response to step 1.3.2 having been carried out, fusing the fusible material at the locations of L_iusing the i^th-beam source after step 1.3.2.